EXHIBIT 5
                                                                       ---------



                         PARTNERSHIP PURCHASE AGREEMENT



BETWEEN:


                                   NEXEN INC.


                                     - and -


                            CANADIAN NEXEN YEMEN LTD.

                                     - and -

                                 NEXEN MARKETING


                                     - AND -


                           HARVEST BREEZE TRUST NO. 1


                                      -and-


                           HARVEST BREEZE TRUST NO. 2




                              (NEXEN CANADA NO. 1)




                                TABLE OF CONTENTS
                                                                            PAGE

1.      INTERPRETATION.........................................................1

2.      PURCHASE AND SALE.....................................................15

3.      ADJUSTMENTS...........................................................19

4.      CLOSING...............................................................21

5.      MAINTENANCE OF THE ASSETS.............................................22

6.      TITLE AND ENVIRONMENTAL REVIEW........................................26

7.      THIRD PARTY RIGHTS AND CONSENTS.......................................29

8.      VENDOR'S REPRESENTATIONS..............................................31

9.      PURCHASER'S REPRESENTATIONS...........................................38

10.     NO MERGER AND SURVIVAL................................................39

11.     INDEMNITIES...........................................................39

12.     VENDOR'S CLOSING CONDITIONS...........................................42

13.     PURCHASER'S CLOSING CONDITIONS........................................42

14.     TERMINATION...........................................................44

15.     DEFAULT...............................................................44

16.     DISPUTE RESOLUTION....................................................45

17.     EMPLOYMENT MATTERS....................................................45

18.     PROTECTION OF PERSONAL INFORMATION....................................46

19.     POST-CLOSING OBLIGATIONS..............................................48

20.     CONFIDENTIALITY.......................................................50

21.     ATTORNMENT AND PROPER LAW.............................................51

22.     MISCELLANEOUS.........................................................51




                         PARTNERSHIP PURCHASE AGREEMENT

                  THIS AGREEMENT made as of the 23rd day of June, 2005,

BETWEEN:

                  NEXEN INC., a body corporate having offices at the City of
                  Calgary, in the Province of Alberta

                  (hereinafter referred to as "NEXEN")

                                     - and -

                  CANADIAN NEXEN YEMEN LTD., a body corporate having offices at
                  the City of Calgary, in the Province of Alberta,

                  (hereinafter referred to as "CNYL")

                                     - and -

                  NEXEN MARKETING, a general partnership having offices at the
                  City of Calgary, in the Province of Alberta,

                  (hereinafter referred to as "Nexen Marketing")

                                     - AND -

                  HARVEST BREEZE TRUST NO. 1, a trust established pursuant to
                  the laws of Alberta, by its trustee, 1115638 ALBERTA LTD.,
                  having offices at the City of Calgary, in the Province of
                  Alberta,

                  (hereinafter referred to as "BREEZE NO. 1")

                                      -and-

                  HARVEST BREEZE TRUST NO. 2, a trust established pursuant to
                  the laws of Alberta, by its trustee, 1115650 ALBERTA LTD.,
                  having offices at the City of Calgary, in the Province of
                  Alberta

                  (hereinafter referred to as "BREEZE NO. 2")



                  WHEREAS the Vendor desires to sell the Securities, Pipeline,
Nexen Seismic and Office and Administrative Assets to the Purchaser and the
Purchaser desires to purchase the Securities, Pipeline, Nexen Seismic and Office
and Administrative Assets from the Vendor;


                  NOW THEREFORE in consideration of the premises hereto and of
the covenants, warranties, representations, agreements and payments herein set
forth and provided for, the parties hereto covenant and agree as follows:

1.       INTERPRETATION

                                      -2-


         (a)      In this Agreement (including the premises hereto, this clause
                  and each Schedule) the words and phrases set forth below shall
                  have the meaning ascribed thereto below, namely:

                  (i)      "ABANDONMENT AND RECLAMATION OBLIGATIONS" means all
                           remediation and reclamation obligations whatsoever of
                           the Partnership or Vendor, as applicable, including,
                           without limitation:

                           A.       the abandonment and reclamation of any
                                    Wells, and the restoration of the surface in
                                    respect thereof including any related roads;
                                    and

                           B.       the closure, decommissioning and dismantling
                                    of Tangibles, and the restoration of the
                                    surface in respect thereof including any
                                    related roads;

                           all in accordance with good oil and gas field
                           practices, and in compliance with the Regulations;

                  (ii)     "ADJUSTED WORKING CAPITAL" means an amount equal to
                           the Current Assets less the Current Liabilities as at
                           the Closing Date excluding all amounts receivable by
                           the Partnership from, or payable by the Partnership
                           to, NEXEN including amounts accrued;

                  (iii)    "AFFILIATES" means with respect to any Person, any
                           other Person which is affiliated with such Person,
                           and for the purposes of this Agreement:

                           A.       two Persons will be considered to be
                                    affiliated with one another if one of them
                                    controls the other, or if both of them are
                                    controlled by a common third Person; and

                           B.       one Person will be considered to control
                                    another Person if it has the power to direct
                                    or cause the direction of the management and
                                    policies of the other Person, whether
                                    directly or indirectly, through one or more
                                    intermediaries or otherwise, and whether by
                                    virtue of the ownership of partnership
                                    interest or other equity interests, the
                                    holding of voting rights or contractual
                                    rights, or otherwise;

                           and for greater certainty, Nexen Canada No. 1 and
                           Subco are Affiliates of the Vendor prior to Closing
                           and Affiliates of Harvest Operations Corp. and
                           Harvest Energy Trust are Affiliates of the Purchaser
                           and the Purchasers are Affiliates of Harvest Energy
                           Trust for the purposes of this Agreement;

                  (iv)     "ASSETS" means the Partnership's entire right, title
                           and interest in and to all assets within the area
                           outlined in purple on the land plat contained
                           attached hereto as Schedule "F" including, without
                           limitation, the Petroleum and Natural Gas Rights, the
                           Tangibles, the Technical Information and the
                           Miscellaneous Interests;

                  (v)      "BUSINESS DAY" means a day other than a Saturday, a
                           Sunday or a statutory holiday in Calgary, Alberta;

                  (vi)     "CLAIMS PERIOD" means:

                           A.       in respect of the representations and
                                    warranties set out in Clause 8(a) (xviii),
                                    (xxi) and (xxii), and the indemnity for
                                    Subco income taxes in


                                      -3-


                                    Clause 11(a) (B), the period ending on the
                                    day which is sixty (60) days after expiry of
                                    all reassessment periods in respect of the
                                    First Fiscal Period for the Partnership and
                                    any taxation years of Subco which ended or
                                    end prior to the Closing Date; and

                           B.       for all other indemnities, representations,
                                    warranties, covenants and agreements of
                                    Vendor, the period ending twelve (12) months
                                    after the Closing Date;

                  (vii)    "CLOSING" means the conveyance of the Securities,
                           Pipeline, Nexen Seismic and Office and Administrative
                           Assets by the Vendor to the Purchaser and the payment
                           by the Purchaser to the Vendor of the Purchase Price
                           therefor and the completion of all matters incidental
                           thereto on the Closing Date at the Place of Closing;

                  (viii)   "CLOSING DATE" means 2:00 p.m. (Calgary, Alberta
                           time) on the 2nd day of August, 2005 or such other
                           time as may be agreed to by the Vendor and the
                           Purchaser;

                  (ix)     "CURRENT ASSETS" means the aggregate of all the
                           Partnership's current assets calculated in accordance
                           with GAAP, including in such calculation any balance
                           of pre-paid amounts, any deposits or advances, and
                           the entire Intercompany Receivable;

                  (x)      "CURRENT LIABILITIES" means the aggregate of all the
                           Partnership's current liabilities calculated in
                           accordance with GAAP, including in such calculation
                           the entire Intercompany Payable;

                  (xi)     "DATA ROOM MATERIALS" means the documents, files,
                           data and information which were in the Vendor's data
                           room during the period April 5, 2005 to May 9, 2005
                           as set forth in the CD or CD's attached hereto as
                           Schedule "G";

                  (xii)    "EFFECTIVE DATE" means 12:01 a.m. (Calgary, Alberta
                           time) on the 1st day of April, 2005;

                  (xiii)   "ENVIRONMENTAL DEFECT" means Environmental
                           Liabilities relating to the Assets and the Pipeline
                           or the surface areas associated therewith, provided
                           however, the following shall be deemed to not be an
                           Environmental Defect:

                           A.       Environmental Liabilities disclosed in the
                                    Data Room Materials; and

                           B.       Abandonment and Reclamation Obligations but
                                    only to the extent of Environmental
                                    Liabilities that are normally associated
                                    with assets which are similar to the Assets
                                    and which have been operated in compliance
                                    with the Regulations, the Title and
                                    Operating Documents and good oilfield
                                    practices;

                  (xiv)    "ENVIRONMENTAL EVALUATOR" means Earthmaster
                           Environmental Strategies Inc. or such other party as
                           agreed to by the Parties;

                  (xv)     "ENVIRONMENTAL LIABILITIES" means all liabilities
                           pertaining to the Assets and the Pipeline in respect
                           of the environment, whether or not caused by a breach
                           of the applicable Regulations and whether or not
                           resulting from operations however


                                      -4-

                           and whenever conducted with respect to the Assets and
                           the Pipeline, including, without limitation,
                           liabilities related to:

                           A.       the transportation, storage, use or disposal
                                    of toxic or hazardous substances, dangerous
                                    oilfield waste or non-dangerous oilfield
                                    waste;

                           B.       the release, spill, escape or emission of
                                    toxic or hazardous substances;

                           C.       any other pollution or contamination of the
                                    surface, substrate, soil, air, ground water,
                                    surface water or marine environments;

                           D.       damages and losses suffered by Third Parties
                                    as a result of the occurrences in Paragraphs
                                    (A) - (C) of this Clause; and

                           E.       any obligations imposed by the Regulations
                                    to protect the environment or to rectify
                                    environmental problems;

                  (xvi)    "FACILITIES" means all unit facilities under any unit
                           agreement that applies to the Petroleum and Natural
                           Gas Rights and all other field facilities that are
                           not solely located on or under the surface of the
                           Lands (or lands with which the Lands are pooled) and
                           that are used for production, gathering, treatment,
                           compression, transportation, injection, water
                           disposal, measurement, processing, storage or other
                           operations respecting the Petroleum and Natural Gas
                           Rights or the Petroleum Substances produced
                           therefrom, including, without limitation, any
                           applicable battery, separator, compressor station,
                           gathering system, pipeline, production storage
                           facility or warehouse and all other facilities
                           specifically identified in Schedule "B" attached
                           hereto;

                  (xvii)   "FINANCIAL INFORMATION" means financial information
                           relating to the Partnership, the Assets and the
                           Pipeline, including (i) source records, books,
                           general ledger, gathering and processing records,
                           invoices, operating statements in Vendors' or their
                           Affiliates' possession or to which it has reasonable
                           access, and (ii) other financial statements and
                           summaries previously prepared by the Vendors or their
                           Affiliates in association with the Partnership and
                           the Assets (to the extent they are in the possession
                           and control of the Vendor), including:

                           A.       audited statements of revenue, royalties and
                                    operating expenses associated with the
                                    Assets for the period ended December 31,
                                    2002, December 31, 2003 and December 31,
                                    2004 together with Deloitte & Touche LLP's
                                    audit report thereon in the form prepared;

                           B.       unaudited statements of revenue, royalties
                                    and operating expenses associated with the
                                    Assets for the most recently completed
                                    interim period at or prior to the Closing
                                    Date and the comparable period in the
                                    preceding financial year, together with
                                    Deloitte & Touche LLP's review engagement
                                    report thereon; and

                           C.       such other related information that is
                                    required under securities laws and
                                    Regulations to be disclosed by the Purchaser
                                    in connection with future securities
                                    filings;

                  (xviii)  "FUTURES TRANSACTION" means any derivatives
                           transaction (including an agreement with respect
                           thereto) which is commonly referred to as a hedge
                           transaction, rate swap transaction, basis swap,
                           forward rate transaction,


                                      -5-


                           commodity swap, commodity option, equity or equity
                           index swap, equity or equity index option, bond
                           option, interest rate option, foreign exchange
                           transaction, cap transaction, floor transaction,
                           collar transaction, currency swap transaction,
                           cross-currency rate swap transaction, currency option
                           or any other similar transaction (including any
                           option with respect to any of these transactions) or
                           any combination of these transactions;

                  (xix)    "GAAP" means generally accepted accounting principles
                           established by the Canadian Institute of Chartered
                           Accountants at the relevant time;

                  (xx)     "INTERCOMPANY PAYABLE" means all accounts payable,
                           including amounts accrued, by the Partnership to the
                           Vendor or any Affiliate of the Vendor including any
                           amount owing under any promissory notes granted by
                           the Partnership in favor of the Vendor or any
                           Affiliate of the Vendor, if any, excluding all
                           amounts payable by the Partnership to NEXEN including
                           all amounts accrued;

                  (xxi)    "INTERCOMPANY RECEIVABLE" means all accounts
                           receivable, including amounts accrued, held by the
                           Partnership for amounts owing by the Vendor or any
                           Affiliate of the Vendor including any amount owing
                           under any promissory notes granted by the Vendor or
                           any Affiliate of the Vendor in favor of the
                           Partnership, if any, excluding all amounts receivable
                           by the Partnership from NEXEN including all amounts
                           accrued;

                  (xxii)   "LANDS" means the Partnership's entire interest in
                           and to those lands within the areas outlined in
                           purple on the land plat contained in the CD attached
                           hereto as Schedule "F" including, without limitation,
                           the lands set forth and described in attached
                           Schedule "A" and the Petroleum Substances within,
                           upon and under such lands, together with the right to
                           explore for and recover same, all insofar as such are
                           granted by the Leases;

                  (xxiii)  "LEASES" means, collectively, the various leases,
                           licences, permits, reservations, certificates of
                           title and other documents of title which the holder
                           may explore for, drill for, recover, remove or
                           dispose of Petroleum Substances within, upon or under
                           the Lands (or lands with which the Lands are pooled
                           or unitized) and includes, if applicable, all
                           renewals and extensions of those documents and all
                           documents issued in substitution therefore, including
                           without limitation, those set forth in the CD or CD's
                           attached hereto as Schedule "A";

                  (xxiv)   "LOSSES AND LIABILITIES" means all claims,
                           liabilities, actions, proceedings, demands, losses,
                           costs, penalties, fines, damages and expenses which
                           may be sustained or incurred by any of a Party, its
                           directors, officers, agents, and employees,
                           including, without limitation, reasonable legal fees
                           and disbursements on a solicitor and client basis;

                  (xxv)    "MISCELLANEOUS INTERESTS" means subject to the
                           limitations and exclusions in this definition and in
                           the definition of "Assets", the Partnership's entire
                           interest in all property and rights, other than the
                           Petroleum and Natural Gas Rights, Tangibles and
                           Technical Information, to the extent they pertain
                           directly to the Petroleum and Natural Gas Rights, the
                           Tangibles or the Technical Information including,
                           without limitation:

                           A.       the Title and Operating Documents;

                           B.       the Surface Rights;


                                      -6-


                           C.       the well bores and down hole casing
                                    respecting the Wells; and

                           D.       copies of geological, engineering, facility
                                    and other records, files, reports, data,
                                    correspondence and documents, or portions
                                    thereof, that relate directly to the Assets;

                  (xxvi)   "NEXEN SEISMIC" means with respect to proprietary
                           seismic data in which NEXEN owns less than 100%
                           interest: subject to approval of the operators and
                           NEXEN's partners and only upon terms and conditions
                           approved by those Persons, licensed copies thereof
                           including all seismic records, books, documents and
                           reports (excluding all proprietary and associated
                           trading rights relating to such data) which seismic
                           lines are shown on the land plat in Schedule "F" and
                           which may include, without limitation, data,
                           documents and information similar to those described
                           in paragraphs 1(a)(x1v)(A) to (D);

                  (xxvii)  "OFFICE AND ADMINISTRATIVE ASSETS" means NEXEN's
                           entire right, title and interest (whether leased,
                           rented or owned) in and to any field offices and
                           administrative buildings, vehicles, office equipment,
                           computers, furnishings, furniture, artwork, fittings,
                           fixtures, oilfield equipment, systems (including,
                           without limitation, all SCADA systems pertaining to
                           the Assets but excluding other licensed and
                           proprietary software that may be excluded as set
                           forth in Schedule "J"), supplies and inventory,
                           whether or not affixed, but located within the area
                           outlined in purple on the land plat contained in the
                           CD attached hereto as Schedule "F" as at the Closing
                           Date, including without limitation, those described
                           in Schedule "J";

                  (xxviii) "PARTNERSHIP" means Nexen Canada No. 1, an Alberta
                           general partnership;

                  (xxix)   "PARTNERSHIP AGREEMENT" means that certain
                           Partnership Agreement dated December 20, 2004, among
                           Nexen Petroleum Canada and CNYL and any amendments
                           thereto;

                  (xxx)    "PARTNERSHIP INTEREST" means a partnership interest
                           in the Partnership on the Closing Date pursuant to
                           and in accordance with the Partnership Agreement
                           including, without limitation, the partners in the
                           Partnership, inherent right, title and interest in
                           and to the Assets, if any, as provided for in the
                           Partnership Agreement as at the Closing Date;

                  (xxxi)   "PARTY" means a Person that is bound by this
                           Agreement, and "Parties" means two or more of such
                           Persons;

                  (xxxii)  "PERMITTED ENCUMBRANCES" means:

                           A.       the terms and conditions of the Title and
                                    Operating Documents, including, without
                                    limitation, any penalty or forfeiture that
                                    applies to the Assets subsequent to the
                                    Effective Date resulting from the
                                    Purchaser's election under Clause 5 not to
                                    participate in a particular operation, and
                                    provided that the following are only
                                    "Permitted Encumbrances" if and to the
                                    extent that the following are detailed in
                                    Schedule "A":

                                    (1)      any overriding royalties, net
                                             profits interests or other
                                             encumbrances applicable to the
                                             Petroleum and Natural Gas Rights
                                             for which the Purchaser will assume
                                             the obligation for payment;


                                      -7-


                                    (2)      any existing potential alteration
                                             of the Partnership's interest in
                                             the Assets because of payout
                                             conversion or farmin, farmout or
                                             other such agreement;

                                    (3)      any Preferential Rights; and

                                    (4)      any penalty or forfeiture that
                                             applies to the Assets at the
                                             Effective Date because of the
                                             Partnership's election not to
                                             participate in a particular
                                             operation;

                            B.      easements, rights of way, servitudes or
                                    other similar rights including, without
                                    limitation, rights of way for highways and
                                    other roads, railways, sewers, drains, gas
                                    or oil pipelines, gas or water mains,
                                    electric light, power, telephone or cable
                                    television towers, poles and wires;

                            C.      the Regulations and any rights reserved to
                                    or vested in any municipality or
                                    governmental, statutory or public authority
                                    to levy taxes or to control or regulate any
                                    of the Assets, Pipeline and Office and
                                    Administrative Assets in any manner,
                                    including, without limitation, the right to
                                    control or regulate the production rates and
                                    the conduct of operations;

                            D.      Statutory exceptions to title and the
                                    reservations, limitations and conditions in
                                    any grants or transfers from the Crown of
                                    any of the Petroleum and Natural Gas Rights
                                    or interests therein;

                            E.      Undetermined or inchoate liens incurred or
                                    created in the ordinary course of business
                                    as security for the Partnership's or
                                    Vendor's, as applicable share of the costs
                                    and expenses of the development or operation
                                    of any of the Assets, Pipeline and Office
                                    and Administrative Assets, which costs and
                                    expenses are not delinquent as of the
                                    Closing Date;

                            F.      Undetermined or inchoate mechanics' liens
                                    and similar liens for which payment for
                                    services rendered or goods supplied is not
                                    delinquent as of the Closing Date;

                            G.      liens granted in the ordinary course of
                                    business to a public utility, municipality
                                    or governmental authority respecting
                                    operations pertaining to any of the Assets,
                                    Pipeline and Office and Administrative
                                    Assets;

                            H.      liens imposed under Regulations securing the
                                    payment of any taxes, assessments or
                                    government charges which are not due or the
                                    validity of which is being contested in good
                                    faith;

                            I.      any lien contemplated by Clauses 1(a)(xxix)
                                    E, F, G and H that is being contested in
                                    good faith by the Vendor; and

                            J.      any defects or deficiencies in title to the
                                    Assets disclosed in the Data Room Materials
                                    or that are waived or deemed to be waived
                                    under Clause 6;

                  (xxxiii)  "PERSON" means an individual, a partnership, a
                            corporation, a trust, an unincorporated
                            organization, a union, a governmental authority and
                            the heirs, executors, administrators or other legal
                            representatives thereof;


                                      -8-


                  (xxxiv)   "PETROLEUM AND NATURAL GAS RIGHTS" means the entire
                            interests of the Partnership, including those
                            described in the CD or CD's attached hereto as
                            Schedule "A", in respect of the Leases to the extent
                            they apply to the Lands, including, without
                            limitation, any existing contractual right of the
                            Partnership to earn an interest under a farmin or
                            similar arrangement, any net carried interest and
                            any overriding royalty, net profits interest or
                            other encumbrance accruing to the Partnership;

                  (xxxv)    "PETROLEUM SUBSTANCES" means crude oil, natural gas
                            and every other mineral or substance, the right to
                            explore for which, or an interest in which, is
                            granted under the Leases, including, without
                            limitation, sulphur (subject to such limitations as
                            to geological formations and Petroleum Substances as
                            may appear in Schedule "A");

                  (xxxvi)   "PIPELINE" means Nexen Marketing's entire interest
                            in and to:

                            A.      the "Hay Pipeline" which is approximately 38
                                    kilometers in length and 219.1 mm (8") in
                                    diameter, commencing at b-76-H/94-I-9 in the
                                    Province of British Columbia and terminating
                                    at 11-17-110-9 W6M in the Province of
                                    Alberta;

                           as shown on the land plat in Schedule "F" and all
                           tangible property and assets whatsoever relating to
                           thereto (including all line fill and Petroleum
                           Substances in the Pipeline as of the Effective Date)
                           including, without limitation, metering equipment,
                           the communication system, inventory, pigging stations
                           and all miscellaneous interests, title and operating
                           documents (including, without limitation, tie-in and
                           contract operating agreements and the Well Effluent
                           Transportation and Processing Agreement dated January
                           1, 2000 originally between Husky Oil Operations
                           Limited, CXY Energy Marketing and Wascana Energy
                           Partnership), surface rights, right of ways and all
                           records, files, reports, data, correspondence and
                           documents whatsoever relating thereto;

                  (xxxvii) "PLACE OF CLOSING" means the offices of the Vendor,
                           located at 2900, 801 - 7th Avenue S.W., Calgary,
                           Alberta;

                  (xxxviii)"PREFERENTIAL RIGHTS" means a right of first refusal,
                           pre-emptive right of purchase or similar contractual
                           right under the Title and Operating Documents or
                           otherwise whereby a Third Party has the right to
                           purchase or acquire any of the Assets because of the
                           Vendor's agreement to dispose of the Assets to the
                           Purchaser hereunder;

                  (xxxix)  "PRIME RATE" means the annual rate of interest in
                           effect at the Effective Date, based upon a year of
                           365 days, designated by the Royal Bank of Canada as
                           its prime rate for Canadian dollar commercial loans;

                  (xl)     "PURCHASE PRICE" means the total consideration
                           payable by the Purchaser to the Vendor at Closing
                           pursuant to Subclause 2(b), as modified by the
                           adjustments and reductions provided for herein;

                  (xli)    "PURCHASER" means:

                          [ INTENTIONALLY DELETED ]


                                      -9-


                          [ INTENTIONALLY DELETED ]

                           as the context requires;

                  (xlii)   "REGULATIONS" means all statutes, laws, rules,
                           regulations, policies, decrees, orders, judgments or
                           directives in effect from time to time and made or
                           issued by a government, governmental body, agency,
                           board, tribunal or court having jurisdiction over the
                           Parties, the Assets or the transaction contemplated
                           herein;

                  (xliii)  "SECURITIES" means:

                           A.       Where NEXEN is the Vendor pursuant to Clause
                                    2(a): NEXEN's entire Partnership Interest in
                                    and to the Partnership on the Closing Date
                                    ("NEXEN PARTNERSHIP INTEREST") pursuant to
                                    and in accordance with the Partnership
                                    Agreement and all amounts receivable by
                                    NEXEN from the Partnership as of the Closing
                                    Date including all amounts accrued
                                    (collectively the "NEXEN RECEIVABLES"); and

                           B.       Where CNYL is the Vendor pursuant to Clause
                                    2(a): CNYL's entire interest in and to the
                                    issued and outstanding shares in the capital
                                    of Subco (the "CNYL SUBCO SHARES");

                           as context requires;

                  (xliv)   "SUBCO" means CNYL No. 1 Ltd., an Alberta corporation
                           wholly owned by CNYL and which, as of the Closing
                           Date, owns a 0.1% Partnership Interest in and to the
                           Partnership;

                  (xlv)    "SURFACE RIGHTS" means all rights to use the surface
                           of land in connection with the Assets, including,
                           without limitation, rights to enter upon and occupy
                           the surface of the land on which the Tangibles and
                           the Wells are located and rights to cross or
                           otherwise use the surface of land for access to the
                           Assets;

                  (xlvi)   "TANGIBLES" means the Partnership's entire interest
                           in and to:

                           A.       the Facilities;

                           B.       all tangible property and assets, other than
                                    the Facilities, that are located on or under
                                    the surface of the Lands or lands
                                    appurtenant thereto (or lands with which the
                                    Lands are pooled) and are used or useful
                                    solely for


                                      -10-


                                    production, gathering, treatment,
                                    compression, transportation, injection,
                                    water disposal, measurement, processing,
                                    storage or other operations respecting the
                                    Petroleum and Natural Gas Rights, and
                                    including, without limitation, any equipment
                                    and material inventory that has been charged
                                    to and acquired by the Partnership for the
                                    joint account of the particular owners of
                                    the Assets;

                           C.       the pipeline which is approximately 100
                                    meters in length, commencing at 11-17-110-9
                                    W6M in the Province of Alberta and
                                    terminating at Husky Energy Inc.'s Rainbow
                                    Lake Satellite at 10-17-110-9 W6M in the
                                    Province of Alberta (including the metering
                                    station equipment at 11-17-110-09 W6M); and

                           D.       any additional items that are specifically
                                    indicated in a Schedule attached hereto to
                                    be included as Tangibles;

                  (xlvii)  "TAX ACT" means the Income Tax Act (Canada)
                           R.S.C.1985, 5th Supplemental C-1, and the regulations
                           thereunder as amended, and any applicable legislation
                           of any Province or Territory of Canada with respect
                           to the taxation of income;

                  (xlviii) "TECHNICAL INFORMATION" means the Partnership's
                           entire interest in and to copies of NEXEN's 100%
                           owned proprietary seismic data, including all seismic
                           records, books, documents and reports (excluding all
                           proprietary and associated trading rights relating to
                           such data), which seismic lines are shown on the land
                           plat in the CD attached hereto as Schedule "F", and
                           which may include, without limitation:

                           A.       copies of: all permanent records of basic
                                    field data including, but not limited to,
                                    any and all microfilm or paper copies of
                                    seismic, driller's reports, monitor records,
                                    observer's reports and survey notes and any
                                    and all copies of magnetic field tapes or
                                    conversions thereof;

                           B.       copies of: all permanent records of the
                                    processed field data including, but not
                                    limited to, pre- and post-stacked record
                                    sections including amplitude, phase and
                                    structural displays, post-stacked data
                                    manipulations including filters, migrations
                                    and wavelet enhancements, and any and all
                                    copies of final stacked tapes and any
                                    manipulations and conversions thereof;

                           C.       in the case of 3D seismic, in addition to
                                    the foregoing, copies of all permanent
                                    records of bin locations, bin fold, static
                                    corrections, surface elevations and any
                                    other relevant information. For copies of
                                    all 100 % proprietary 3D seismic data sets,
                                    a copy of the existing Geoquest workstation
                                    project for those 3D seismic datasets. The
                                    copy will be in 8 mm exabyte format and the
                                    project will have at least one version of
                                    each 3D purchased, with interpretations
                                    (horizons picked); and

                           D.       copies of: any support data relating to the
                                    foregoing, including surveyors' ground
                                    elevation records, shot point maps,
                                    drillers' logs, shooters' records,
                                    seismograph records, seismograph magnetic
                                    tapes, monitor records, field records and
                                    record sections, including maps and
                                    interpretations made from any of the
                                    foregoing;

                  (xlix)   "THIRD PARTY" means any Person other than the
                           Parties;


                                      -11-


                  (l)      "THIRTEENTH MONTH ADJUSTMENT" means the accounting
                           procedure performed annually by an operator of
                           particular Tangibles for the purpose of
                           redistributing certain revenues and expenses,
                           including, without limitation, operating expenses,
                           processing fee revenues, excess capacity utilization
                           fees and recoveries, royalties and gas cost
                           allowances (or similar cost allowances);

                  (li)     "TITLE AND OPERATING DOCUMENTS" means, to the extent
                           directly related to the Petroleum and Natural Gas
                           Rights, the Tangibles and the Technical Information,
                           or any of them:

                           A.       the Leases;

                           B.       agreements affecting the Partnership's
                                    interests in the Petroleum and Natural Gas
                                    Rights, including, without limitation,
                                    operating agreements, royalty agreements,
                                    farmout or farmin agreements, option
                                    agreements, participation agreements,
                                    pooling agreements, sale and purchase
                                    agreements and asset exchange agreements;

                           C.       agreements for the sale of Petroleum
                                    Substances that are terminable on 31 days'
                                    notice or less (without an early termination
                                    penalty or other cost) or that are
                                    identified in Schedule "E" attached hereto;

                           D.       agreements respecting the unitization of any
                                    of the Petroleum and Natural Gas Rights;

                           E.       agreements pertaining to the Surface Rights;

                           F.       agreements for the construction, ownership
                                    and operation of the Tangibles;

                           G.       service agreements for the treating,
                                    gathering, storage, transportation or
                                    processing of Petroleum Substances or other
                                    third party petroleum substances, the
                                    injection or subsurface disposal of
                                    substances, the use of well bores or the
                                    operation of any Wells or Tangibles by a
                                    third party;

                           H.       any approvals, authorizations or licences
                                    required under the Regulations for the
                                    conduct of operations with respect to the
                                    Assets, including, without limitation, Well,
                                    pipeline and plant licences; and

                           I.       all other agreements that relate to the
                                    ownership, operation or exploitation of the
                                    Petroleum and Natural Gas Rights or the
                                    Tangibles;

                  (lii)    "TITLE DEFECTS" means a deficiency or discrepancy in
                           or affecting the title of the Partnership in and to
                           any of the Assets or the Vendor in and to the
                           Pipeline and the Office and Administrative Assets,
                           but specifically excludes, without limitation:

                           A.       any Title Defect, deficiency, discrepancy,
                                    matter or thing which was disclosed in the
                                    Data Room Materials, PROVIDED HOWEVER,
                                    subject to the terms of this Agreement,
                                    excluding any specific Title Defect in
                                    respect of the Assets, the Pipeline or the
                                    Office and Administrative Assets discovered
                                    during the Purchaser's full title review by
                                    its outside counsel conducted after the date
                                    of this Agreement which could not have


                                      -12-


                                    been reasonably discovered by the Purchaser
                                    as a result of the Purchaser's review of the
                                    Data Room Materials;

                           B.       any deficiency or discrepancy relating to
                                    any preferential rights or similar rights
                                    which may or may not have been applicable as
                                    a result of the Vendor's contribution of the
                                    Assets to the Partnership or as a result of
                                    any previous internal reorganization of the
                                    Vendor and its Affiliates;

                           C.       the loss of lease acreage between the
                                    Effective Date and the Closing Date because
                                    the lease term expires;

                           D.       the Permitted Encumbrances;

                           E.       the mere fact that any beneficial, rather
                                    than legal, interest of the Partnership or
                                    any of its predecessors in the Assets if
                                    that beneficial interest is held in trust
                                    under the Leases or the Title and Operating
                                    Documents;

                           F.       any liens or encumbrances against the
                                    interest of a Third Party that do not
                                    pertain to the interest of the Partnership
                                    in the Assets; and

                           G.       any missing or unsigned documents in the
                                    chain of the Partnership's title to the
                                    Assets or Vendor's title to the Pipeline and
                                    Office and Administrative Assets where such
                                    document is not reasonably required to
                                    confirm the creation, establishment or
                                    maintenance of such title and provided the
                                    current status of title can otherwise be
                                    confirmed with reasonable certainty;

                  (liii)   "TITLE EVALUATOR" means a senior partner of Thackray
                           Burgess LLP or such other independent oil and gas
                           solicitor as may be agreed to by the Parties;

                  (liv)    "VENDOR" means:

                           A.       With respect to the sale of the Office and
                                    Administrative Assets and Nexen Seismic,
                                    NEXEN;

                           B.       With respect to the Sale of the Securities,
                                    NEXEN and CNYL as set out in Clause 2(a);
                                    and

                           C.       With respect to the sale of the Pipeline,
                                    Nexen Marketing;

                           as the context requires;

                 [ INTENTIONALLY DELETED ]

                  (lvi)    "WELLS" means the Partnership's entire interest in
                           all wells within the area outlined in purple on the
                           land plat attached hereto as Schedule "F" including,
                           without limitation, any producing, capped, shut-in,
                           suspended, abandoned, disposal, water source,
                           observation, injection and other wells located on


                                      -13-


                           the Lands or on lands with which the same have been
                           pooled or unitized as set out in Schedule "C".

         (b)      Attached hereto are the following Schedules:

                  (i)      Schedule "A" - Lands, Leases, Petroleum and Natural
                           Gas Rights

                  (ii)     Schedule "B"       -       Facilities

                  (iii)    Schedule "C"       -       Wells

                  (iv)     Schedule "D"       -       Authorizations for
                                                      Expenditure

                  (v)      Schedule "E"       -       Marketing Contracts

                  (vi)     Schedule "F"       -       Land Plat

                  (vii)    Schedule "G"       -       Data Room Materials (CD)

                  (viii)   Schedule "H"       -       Litigation

                  (ix)     Schedule "I"       -       Field Employees

                  (x)      Schedule "J"       -       Office and Administrative
                                                      Assets

                  All Schedules hereto are incorporated into and as part of this
                  Agreement by this reference as fully as though contained in
                  the body of this Agreement.

         (c)      The headings of clauses and subclauses herein and in the
                  Schedules are inserted for convenience of reference only and
                  shall not affect or be considered to affect the construction
                  of the provisions hereof.

         (d)      Wherever any provision of any Schedule to this Agreement
                  conflicts with any provision in the body of this Agreement,
                  the provisions of the body of this Agreement shall prevail.
                  References herein to a Schedule shall mean a reference to the
                  applicable Schedule to this Agreement. References in any
                  Schedule to the "Agreement" shall mean a reference to this
                  Agreement. References in any Schedule to another Schedule
                  shall mean a reference to a Schedule to this Agreement.

         (e)      Any reference herein to a statute shall include and shall be
                  deemed to be a reference to such statute and to the
                  regulations made pursuant thereto, and all amendments made
                  thereto and in force from time to time, and to any statute or
                  regulation that may be passed which has the effect of
                  supplementing or superseding the statute so referred to or the
                  regulations made pursuant thereto.

         (f)      If any of the provisions of this Agreement should be
                  determined to be invalid, illegal or unenforceable in any
                  respect, the validity, legality or enforceability of the
                  remaining provisions herein shall not in any way be affected
                  or impaired thereby.

         (g)      Where in this Agreement a representation and warranty is made
                  on the basis of the knowledge or awareness of a Party hereto,
                  such knowledge or awareness consists only of the actual
                  knowledge or awareness, as the case may be, of the current
                  officers, servants, agents and employees of such Party who are
                  responsible for the supervision of the


                                      -14-


                  subject matter of such representation or warranty, but shall
                  not include the knowledge or awareness of any other person or
                  persons.

         (h)      All references to "Dollars" or "$" herein shall refer to
                  lawful currency of Canada.

         (i)      The terms "Agreement", "hereof", "herein", "hereunder" and
                  similar expressions refer to this Agreement, including any
                  Schedules hereto, taken as a whole and not to any particular
                  article, section, subsection, clause, or subclause or other
                  subdivision thereof and include any agreement or instrument
                  which amends, modifies or is supplementary to this Agreement.

         (j)      In this Agreement, words importing persons include
                  corporations and vice versa, words importing the masculine
                  gender include the feminine and neuter genders and vice versa,
                  and words importing the singular include the plural and vice
                  versa.

         (k)      Joint Vendor:

                  (i)      Except as otherwise provided herein, all rights,
                           benefits, obligations and liabilities accruing to or
                           assumed by the Vendor under this Agreement and the
                           Regulations shall be: solely NEXEN's responsibility
                           with respect to a sale of the Nexen Seismic and
                           Office and Administrative Assets; Nexen Marketing's
                           responsibility with respect to the sale of the
                           Pipeline; and, both joint and several as between
                           NEXEN and CNYL with respect to a sale of Securities.

                  (ii)     With respect to any decision or election to be made
                           by Vendor under this Agreement, NEXEN and CNYL with
                           respect to a sale of Securities, shall make such
                           election jointly so that Purchaser is not required to
                           pursue different courses of action with each of them.

                  (iii)    If either one of NEXEN and CNYL with respect to a
                           sale of Securities, but not both, are unable to or
                           unwilling to close this transaction for any reason
                           permitted herein, then Purchaser shall not be
                           required to complete this transaction with the other
                           party comprising Vendor, and that other Party
                           comprising Vendor shall be deemed to have defaulted
                           under this Agreement or elected to terminate this
                           transaction, as applicable, on the same basis as the
                           first-mentioned Vendor Party.

         (l)      Joint Purchaser:

                  (i)      Except as otherwise provided herein, all rights,
                           benefits, obligations and liabilities accruing to or
                           assumed by the Purchaser under this Agreement and the
                           Regulations shall be both joint and several as
                           between BREEZE NO. 1 and BREEZE NO. 2.

                  (ii)     With respect to any decision or election to be made
                           by Purchaser under this Agreement, BREEZE NO. 1 and
                           BREEZE NO. 2, shall make such election jointly so
                           that Vendor is not required to pursue different
                           courses of action with each of them.

                  (iii)    If either one of BREEZE NO. 1 and BREEZE NO. 2, but
                           not both, are unable to or unwilling to close this
                           transaction for any reason permitted herein, then
                           Vendor shall not be required to complete this
                           transaction with the other party comprising
                           Purchaser, and that other Party comprising Purchaser
                           shall be deemed to have defaulted under this
                           Agreement or elected to terminate this transaction,
                           as applicable, on the same basis as the
                           first-mentioned Purchaser


                                      -15-


                           Party

2.       PURCHASE AND SALE

         (a)      Upon the terms and subject to the conditions of this
                  Agreement, the Purchaser will purchase the Securities,
                  Pipeline, Nexen Seismic and Office and Administrative Assets
                  from the Vendor and make payment therefor to the Vendor and
                  the Vendor will sell, assign and deliver the Securities,
                  Pipeline, Nexen Seismic and Office and Administrative Assets
                  to the Purchaser upon receipt of that part of the Purchase
                  Price payable on Closing as follows:

                  (i)      Purchaser will purchase CNYL's entire interest in and
                           to the Securities and make payment therefor, as
                           provided for in Clause 2(b) herein, to NEXEN for and
                           on behalf of CNYL, and CNYL will sell, assign and
                           deliver its entire interest in and to the Securities
                           to Purchaser on the Closing Date;

                  (ii)     Purchaser will purchase NEXEN's entire interest in
                           and to the Securities and make payment therefor, as
                           provided for in Clause 2(b) herein, to NEXEN and
                           NEXEN will sell, assign and deliver its entire
                           interest in and to the Securities to Purchaser on the
                           Closing Date;

                  (iii)    Purchaser will purchase NEXEN's entire interest in
                           and to the Office and Administrative Assets and make
                           payment therefor, as provided for in Clause 2(b)
                           herein, to NEXEN and NEXEN will sell, assign and
                           deliver its entire interest in and to the Office and
                           Administrative Assets to Purchaser on the Closing
                           Date;

                  (iv)     Purchaser will purchase Nexen Marketing's entire
                           interest in and to the Pipeline and make payment
                           therefor, as provided for in Clause 2(b) herein, to
                           NEXEN, for and on behalf of Nexen Marketing, and
                           Nexen Marketing will sell, assign and deliver its
                           entire interest in and to the Pipeline to Purchaser
                           on the Closing Date; and

                  (v)      Purchaser will purchase NEXEN's entire interest in
                           and to the Nexen Seismic and make payment therefor,
                           as provided for in Clause 2(b) herein, to NEXEN and
                           NEXEN will sell, assign and deliver its entire
                           interest in and to the Nexen Seismic to Purchaser on
                           the Closing Date.

         (b)      The consideration to be paid by the Purchaser to the Vendor
                  for the sale, assignment and delivery of the Securities,
                  Pipeline, Nexen Seismic and Office and Administrative Assets
                  by the Vendor to the Purchaser shall be the sum of Two Hundred
                  and Sixty Million ($260,000,000.00) Dollars, plus all amounts
                  receivable by the Partnership from NEXEN as of the Closing
                  Date including all amounts accrued (collectively the "NEXEN
                  PAYABLES"), plus or minus the adjustments to the Purchase
                  Price as provided for herein, which sum less the Deposit
                  applied under Clause 2(h) shall be paid in accordance with
                  Clauses 2(g) and 2(i) on the Closing Date to NEXEN for and on
                  behalf of the Vendor. [ INTENTIONALLY DELETED ]:


                                      -16-


                 [ INTENTIONALLY DELETED ]



                                      -17-


         (d)      Notwithstanding anything contained in this Agreement but
                  subject to Clauses 6 and 11, the Parties acknowledge and agree
                  that all revenue, benefits, liabilities and obligations
                  relating to the Assets accruing prior to the Effective Date
                  shall be to the sole benefit and account of the NEXEN as a
                  partner in the Partnership and CNYL as the sole shareholder of
                  Subco which is a partner in the Partnership and Nexen
                  Marketing with respect to the Pipeline, and the Purchaser
                  hereby waives, subject to Clause 11 and in particular Clause
                  11(c), any and all rights to such revenue, benefits,
                  liabilities and obligations for the period prior to the
                  Effective Date which the Purchaser has or may have. The
                  Parties agree that any final allocations and adjustments that
                  are required or necessary under this Clause 2(d) shall be
                  included in the final Adjustment Report prepared in accordance
                  with Clause 3.

         (e)      If Vendor is required to collect from the Purchaser any tax,
                  fee or charge under the Regulations in connection with the
                  Purchaser acquiring the Securities, Pipeline, Nexen Seismic
                  and Office and Administrative Assets, then the Purchaser shall
                  pay the amount of those taxes, fees or charges to the Vendor,
                  and the Vendor shall remit those amounts in the manner
                  required by the Regulations. If the amount of any tax, fee or
                  charge is adjusted as a result of any audit or determination
                  by any government authority then any increase or decrease and
                  any related penalties and interest paid or received shall be
                  paid by or received by the Purchaser.[ INTENTIONALLY DELETED ]

         (f)      The Parties acknowledge and agree that:

                  (i)     [ INTENTIONALLY DELETED ]


                                      -18-


                          [ INTENTIONALLY DELETED ]

                  (iii)    [ INTENTIONALLY DELETED ]

         (g)      Any payment to be made pursuant to this Agreement by the
                  Purchaser shall be made to the Vendor's Bank Account in
                  immediately available funds by electronic transfer in Dollars
                  on the due date for payment. Receipt of such sums in the
                  relevant bank account shall be an effective discharge of the
                  obligation of the Purchaser to pay such sums to the Vendor.]

        [ INTENTIONALLY DELETED ]


                                      -19-


                  If Closing occurs, the Vendor will apply the Deposit (without
                  any adjustment for accrued interest thereon) as partial
                  payment of the Purchase Price in accordance with Clause 2(b).

         (i)      On Closing on the Closing Date, NEXEN shall pay to the
                  Purchaser, as agent of the Partnership, the Nexen Payables.
                  Vendor and Purchaser acknowledge and agree that the Nexen
                  Payables will be fully paid and settled by way of off set
                  against the amount receivable by Vendor from Purchaser
                  pursuant to Clause 2(b).

3.       ADJUSTMENTS

         The Purchase Price shall be subject to the following adjustment
         procedure:

         (a)      On or before Closing, the Vendor shall undertake a review of
                  the Partnership's books and records for the purpose of
                  preparing a report ("ADJUSTMENT REPORT") which shall set forth
                  all adjustments to the Purchase Price under this Agreement and
                  specify the net amount payable under this Clause 3 as follows:

                  (i)      the gross revenue accruing, received or receivable by
                           the Partnership in respect of the Assets from and
                           including the Effective Date up to the Closing Date
                           shall be credited to the account of the Purchaser and
                           result in a decrease in the Purchase Price;

                  (ii)     the gross operating costs and all other costs
                           including, without limitation, royalties, overhead
                           and capital costs determined in accordance with the
                           PASC Accounting Procedure and all insurance costs
                           relating to insurance maintained by the Vendor or the
                           Partnership relating to the Assets accruing, payable
                           or paid by the Partnership in respect of the Assets
                           from and including the Effective Date up to the
                           Closing Date shall be credited to the account of the
                           Vendor and result in an increase in the Purchase
                           Price;

                  (iii)    an amount equal to the interest which would have
                           accrued on the Purchase Price payable on Closing,
                           less the Deposit and the Nexen Payables, from and
                           including the Effective Date to but excluding the
                           Closing Date at the Prime Rate per annum shall be
                           credited to the account of the Vendor and result in
                           an increase in the Purchase Price;

                  (iv)     if the Adjusted Working Capital of the Partnership as
                           of the Closing Date is a positive amount, such amount
                           shall be credited to the account of Vendor and result
                           in an increase in the Purchase Price, and if the
                           Adjusted Working Capital as of the Closing Date is a
                           negative amount, such amount shall be credited to the
                           account of the Purchaser and result in a decrease in
                           the Purchase Price;

                  (v)      if: (A) the current assets, and all accounts
                           receivable, including amounts accrued, held by Subco,
                           if any less, (B) current liabilities, and all
                           accounts payable, including amounts accrued excluding
                           any liabilities in respect of the accounting for
                           future income taxes, by Subco, if any, of Subco
                           determined in accordance with GAAP as of the Closing
                           Date is: (C) a positive amount, such amount shall be
                           credited to the account of Vendor and result in an
                           increase in the Purchase Price; or (D) a negative
                           amount, such amount shall be credited to the account
                           of the Purchaser and result in a decrease in the
                           Purchase Price;

                  (vi)     the gross revenue accruing, received or receivable by
                           the Vendor in respect of the Pipeline from and
                           including the Effective Date up to the Closing Date
                           shall


                                      -20-


                           be credited to the account of the Purchaser and
                           result in a decrease in the Purchase Price;

                  (vii)    the gross operating costs and all other costs
                           including, without limitation, overhead and capital
                           costs determined in accordance with the PASC
                           Accounting Procedure and all insurance costs relating
                           to insurance maintained by the Vendor relating to the
                           Pipeline accruing, payable or paid by the Vendor in
                           respect of the Pipeline from and including the
                           Effective Date up to the Closing Date shall be
                           credited to the account of the Vendor and result in
                           an increase in the Purchase Price; and

                  (viii)   the total value, as agreed to by the Vendor and
                           Purchaser prior to the Closing Date, of the line fill
                           and inventory amount of all Petroleum Substances
                           contained within the Pipeline system as of the
                           Effective Date shall be credited to the account of
                           the Vendor and result in an increase in the Purchase
                           Price.

         (b)      Upon receipt of an Adjustment Report, and subject to Clause
                  3(g), the net amount payable set forth in the Adjustment
                  Report shall be paid by the Party, within ten (10) Business
                  Days following the issuance of the Adjustment Report, who in
                  the net result is obligated to make payment to the other
                  Party, pursuant to the terms and conditions of this Agreement,
                  and such net amount shall result in an increase or decrease,
                  as the case may be, in the Purchase Price as set forth in
                  Clause 2(a). To the extent any Intercompany Receivables and
                  Intercompany Payables have not been settled as of the date of
                  receipt of the Adjustment Report, the Parties agree to settle
                  such amounts within ten (10) Business Days of this date.

         (c)      With respect to any audit which has been commenced, has been
                  completed or notice of which has been received, within
                  twenty-four (24) months of the Closing Date, pertaining to any
                  joint interest or unit operation relating to the Assets
                  participated in by the Partnership, Subco or the Vendor or
                  their Affiliates prior to the Effective Date, and the
                  Partnership (or its assigns) becomes:

                  (i)      obligated to make any refund or other payment and the
                           amount thereof is not reflected in the Adjustment
                           Report, then the Vendor shall forthwith pay to the
                           Purchaser the amount of each such refund or other
                           payment; or

                  (ii)     entitled to receive any refund or other payment and
                           the amount thereof is not reflected in the Adjustment
                           Report, then the Purchaser shall forthwith pay to the
                           Vendor the amount of each such refund or other
                           payment;

                  and the amount of any such payment made shall be deemed to be
                  an adjustment in the Purchase Price.

         (d)      Notwithstanding the foregoing, further adjustments on the
                  basis indicated in this Clause will be made as and when those
                  items arise if notice requesting that adjustment, including
                  reasonable particulars thereof, has been given by a Party to
                  the other Party within thirty (30) days following receipt of a
                  Thirteenth Month Adjustment or a completed and agreed to audit
                  or other report and the need for that adjustment arises from:

                  (i)      a Thirteenth Month Adjustment, operator error
                           adjustments or errors established by joint venture
                           audits within thirty-six (36) months after the
                           Closing Date; or

                  (ii)     errors established by an audit or other review of
                           lessor royalty payments that is


                                      -21-


                           conducted under applicable Regulations or Title and
                           Operating Documents within sixty (60) months after
                           the Closing Date or such later time as may be
                           prescribed by the Regulations.

         (e)      In the event the Parties are unable to agree upon the amount
                  of any adjustment under this Clause 3, the matter may be
                  referred to arbitration in accordance with the provisions of
                  Clause 16, provided however, the amount in the Adjustment
                  Report shall be payable in any event in accordance with Clause
                  3(b) and any arbitration award amending the Adjustment Report
                  shall be deemed to be an amendment thereto.

         (f)      The Purchaser and its nominees, at its sole cost, shall have
                  the right to audit the books, records and accounts of the
                  Vendor and the Partnership for the purposes of confirming the
                  adjustments to the Purchase Price set forth in the Adjustment
                  Report provided for in this Clause 3 at any time during
                  regular business hours up to twelve (12) months following the
                  Closing Date ("AUDIT"). Any disputes relating to an Audit
                  shall be resolved by the agreement of the Parties, failing
                  which the dispute shall be resolved in accordance with Clause
                  16. Notwithstanding the foregoing audit period limitation,
                  Purchaser's audit rights under this Clause 3(f) shall be
                  extended for the time period, and in respect of those books,
                  records and accounts, as may be reasonably necessary to permit
                  Purchaser to verify refunds or payments to be received or made
                  by it pursuant to Clause 3(c).

         (g)      For the purposes of this Clause 3 and the preparation of the
                  Adjustment Report, the Vendor shall:

                  (i)      At least three (3) Business Days prior to the Closing
                           Date prepare an interim Adjustment Report which
                           amounts will be used to adjust the Purchase Price for
                           purposes of settling amounts owing at Closing; and

                  (ii)     Within one hundred and eighty (180) days of the
                           Closing Date prepare the final Adjustment Report;

                  provided that adjustments shall be permitted after this period
                  if required for the purposes of Clause 3(c).

         (h)      Notwithstanding anything to the contrary herein, the Vendor
                  and the Purchaser acknowledge and agree that it is their
                  intention not to double bill or account, adjust, credit or
                  debit for the same item twice pursuant to the adjustments made
                  herein. For greater certainty, one Party shall not receive the
                  same amount twice or have to pay or account for the same item
                  twice (i.e. there shall be no "double dipping").

4.       CLOSING

         (a)      Closing shall take place at the Place of Closing on the
                  Closing Date unless otherwise agreed to by the Vendor and the
                  Purchaser.

         (b)      At Closing the Vendor shall deliver or cause to be delivered
                  to the Purchaser or the Purchaser's solicitors, the following
                  documents, fully executed by Vendor, where applicable:

                  (i)      certificates representing the Securities, if
                           required, accompanied by duly executed instruments of
                           transfer, a bill of sale in respect of the Office and
                           Administrative Assets, Pipeline and Nexen Seismic and
                           any other documents


                                      -22-


                           necessary to transfer to the Purchaser good title to
                           the Securities, Pipeline, Nexen Seismic and Office
                           and Administrative Assets; and

                  (ii)     original partnership minute books and within thirty
                           (30) days of Closing, all environmental, health and
                           safety files and Worker's Compensation files.

         (c)      The Vendor and Purchaser acknowledge and agree that at Closing
                  or as soon as reasonably possible thereafter, the Vendor shall
                  deliver or cause to be delivered to the Purchaser or the
                  Purchaser's solicitors, the following documents, fully
                  executed by the Vendor or Vendor's Affiliates, where
                  applicable:

                  (i)      such transfers, assignments, declarations of trust,
                           novations and other instruments conveying the title
                           to the Assets to the Partnership as may be reasonably
                           required by the Purchaser, provided however, any
                           Surface Rights covered under a "Master Agreement" or
                           similar industry agreement shall not be conveyed;
                           rather the Purchaser shall have sixty (60) days
                           following the Closing Date in which to enter into a
                           "Master Agreement" or similar industry agreement with
                           the applicable Third Party covering such Surface
                           Rights; and

                  (ii)     fully executed releases and discharges of any liens,
                           charges or other encumbrances, other than the
                           Permitted Encumbrances, whatsoever affecting the
                           Assets or a letter in form and content satisfactory
                           to the Purchaser, acting reasonably, from each holder
                           of such security stating that it has no interest in
                           the Assets as security or otherwise howsoever and
                           undertaking to cause to be discharged all
                           encumbrances on the Assets to which such holder is
                           entitled to the benefit.

         (d)      The Vendor shall cooperate, both before and after Closing,
                  with the Purchaser to secure execution of such documents by
                  the Third Parties thereto other than the Vendor and Purchaser.

         (e)      At Closing Vendor shall either provide copies of the documents
                  included in Miscellaneous Interests or undertake to deliver
                  copies of them within ten (10) Business Days following the
                  Closing Date.

         (f)      Unless otherwise agreed to by the Parties, within thirty (30)
                  days following the Closing Date the Vendor, as agent of the
                  Partnership, shall provide the Technical Information and Nexen
                  Seismic to the Purchaser.

5.       MAINTENANCE OF THE ASSETS

         (a)      From the date hereof until the Closing Date (the "INTERIM
                  PERIOD"), the Vendor, as agent for the Partnership and its
                  partners, will maintain the Assets in a proper and prudent
                  manner in accordance with good oil field practice and the
                  Regulations, with such consultation with the Purchaser as is
                  prescribed in this Clause 5 or is otherwise reasonably
                  appropriate in the circumstances. The Vendor, as agent for the
                  Partnership and its partners, will comply with all of the
                  Partnership's obligations with respect to the Assets under the
                  Title and Operating Agreements, will pay when due all expenses
                  and other amounts payable in respect of the Assets during the
                  Interim Period and will maintain any insurance it presently
                  holds respecting the Assets until Closing. Unless otherwise
                  specified herein, the Vendor, as agent for the Partnership and
                  its partners, will not be required to obtain additional
                  insurance respecting the Assets during the Interim Period,
                  except to the extent such insurance is required to be
                  maintained under the Regulations or the Title and Operating
                  Documents. The Vendor, as agent for the Partnership and its
                  partners, will remain the beneficiary under all such policies
                  of


                                      -23-


                  insurance (subject to the insurance benefit contribution
                  provisions of Clause 5(d)) and, unless otherwise agreed by the
                  Parties, the Purchaser will not be entitled to any proceeds of
                  settlement thereunder, provided however, subject to Closing on
                  the Closing Date, the Partnership or the Purchaser, as a
                  partner in the Partnership, or the Purchaser as the purchaser
                  of the Nexen Seismic, Pipeline or Office and Administrative
                  Assets shall be entitled to all insurance proceeds accruing
                  from and after the Effective Date in respect of the Assets,
                  Nexen Seismic, Pipeline and Office and Administrative Assets,
                  as applicable. The Vendor will promptly give notice, in
                  reasonable detail, to the Purchaser upon the Vendor becoming
                  aware of any Environmental Defects and any damage to the
                  Tangibles of the type contemplated in Clause 13(a)(vi).

         (b)      Material Commitments during the Interim Period

                  (i)      During the Interim Period, the Vendor, as agent for
                           the Partnership and its partners, will provide to the
                           Purchaser copies of all AFEs, notices and mail
                           ballots the Vendor, as agent of the Partnership and
                           its partners, the Partnership or Subco receives
                           respecting the Assets, and will not, without the
                           prior written consent of the Purchaser, which consent
                           may not be unreasonably withheld or delayed:

                           A.       Assume any new obligation or commitment
                                    respecting the Assets, if the Partnership's
                                    share of the associated expenditure is
                                    estimated to exceed $50,000.00, except: (i)
                                    for amounts that the Partnership is
                                    committed to expend or is deemed to
                                    authorize under the Title and Operating
                                    Documents without its specific authorization
                                    or approval; or (ii) to the extent that the
                                    Vendor, as agent for the Partnership and its
                                    partners, reasonably determines that those
                                    expenditures or actions are urgently
                                    necessary for the protection or preservation
                                    of life and property, provided that the
                                    Vendor will promptly notify the Purchaser of
                                    any such expenditures or actions;

                           B.       Sell, transfer, or otherwise dispose of any
                                    of the Assets, except for sales of
                                    production of Petroleum Substances
                                    reasonably made by the Vendor, as agent for
                                    the Partnership and its partners, in the
                                    ordinary course of business under sales
                                    arrangements permitted herein;

                           C.       Surrender or abandon any of the Assets;

                           D.       Subject to this Clause 5, amend any of the
                                    Title and Operating Documents (other than
                                    for processing of assignments by third
                                    parties in the ordinary course of business),
                                    terminate any of the Title and Operating
                                    Documents, enter into any new agreement
                                    respecting the Assets or vote on any mail
                                    ballot or other similar notice issued under
                                    the Title and Operating Documents;

                           E.       Subject to Clauses 5(a), 5(b)(i)A and
                                    5(b)(ii), propose or initiate the exercise
                                    of any option arising as a result of the
                                    ownership of the Assets (including, without
                                    limitation, rights under area of mutual
                                    interest provisions and any right of first
                                    refusal) or propose or initiate any
                                    operations with respect to the Assets that
                                    have not been commenced or committed to by
                                    the Vendor, as agent for the Partnership and
                                    its partners, as of the Effective Date, if
                                    that exercise or option would result in an
                                    obligation of the Partnership after the
                                    Effective Date or a material adverse effect
                                    on the value of the Assets;


                                      -24-


                           F.       Other than for Permitted Encumbrances, grant
                                    a security interest or any encumbrance with
                                    respect to any of the Assets;

                           G.       Subject to Clause 5(e), Vendor shall not:

                                    (1)      allow the Partnership to incur,
                                             assume or otherwise become liable
                                             for any debts or charges to the
                                             Vendor, or any affiliate of the
                                             Vendor, except in the ordinary
                                             course of business;

                                    (2)      allow the Partnership to amalgamate
                                             with, merge into or otherwise
                                             consolidate with any other Person
                                             or acquire all or substantially all
                                             of the business or assets of any
                                             other Person; and

                                    (3)      make any change in the constating
                                             documents or by-laws of the
                                             Partnership including, without
                                             limitation, the Partnership
                                             Agreement.

                  (ii)     If an operation or the exercise of any option
                           respecting the Assets is proposed in circumstances
                           which would require the written consent of the
                           Purchaser under Clause 5(b)(i) ("PROPOSAL"):

                           A.       The Vendor will promptly give notice of the
                                    Proposal to the Purchaser, including with
                                    that notice supporting information in
                                    reasonable detail;

                           B.       The Purchaser will advise the Vendor, by
                                    notice, not later than two (2) Business Days
                                    prior to the time the Vendor, as agent for
                                    the Partnership and its partners, is
                                    required to make its election for the
                                    Proposal, if the Purchaser wishes the
                                    Vendor, as agent for the Partnership and its
                                    partners, to exercise its rights on behalf
                                    of the Purchaser, provided that this period
                                    will be reduced to twelve (12) hours if the
                                    period within which the Partnership is
                                    required to reply by notice to the
                                    applicable third parties, is forty eight
                                    (48) hours or less and provided that failure
                                    to make an election within the applicable
                                    period will be deemed to be the Purchaser's
                                    election not to participate in the Proposal;

                           C.       The Vendor will make the election authorized
                                    by the Purchaser for the Proposal within the
                                    period during which the Vendor, as agent for
                                    the Partnership and its partners, may
                                    respond to the Proposal;

                           D.       An election by the Purchaser not to
                                    participate in a Proposal will not result in
                                    any reduction of the Purchase Price if the
                                    Partnership's interest therein is terminated
                                    or altered as a result of that election, and
                                    that termination or alteration will not
                                    constitute a Title Defect or a breach of the
                                    Vendor's representations and warranties; and

                           E.       The Vendor may require the Purchaser to
                                    advance or otherwise secure any costs to be
                                    incurred by the Vendor, as agent for the
                                    Partnership and its partners, on behalf of
                                    the Purchaser under this Clause in such
                                    manner as may be reasonably appropriate in
                                    the circumstances.

                  (iii)    The Purchaser may not, without the written consent of
                           the Vendor, request the Vendor, as agent for the
                           Partnership and its partners, to propose the conduct
                           of any operation respecting the Assets during the
                           Interim Period, except to the


                                      -25-


                           extent provided in this Agreement.

         (c)      Provided Closing occurs and insofar as the Vendor maintained
                  the Assets and took action on behalf of the Partnership
                  pursuant to this Agreement in compliance with the obligations
                  under this Clause 5, the Vendor will be deemed to have been
                  the agent of the Partnership and its partners hereunder. The
                  Purchaser ratifies all actions taken, or refrained from being
                  taken, by the Vendor, as agent for the Partnership and its
                  partners, under this Clause 5 in that capacity, with the
                  intention that all of those actions will be deemed to be those
                  of the Purchaser, as agent of the Partnership, except to the
                  extent that the Vendor's actions under this Clause 5
                  constitute gross negligence or willful misconduct.

         (d)      Provided Closing occurs, Purchaser and the Partnership jointly
                  and severally will:

                  (i)      be liable to Vendor for its Losses and Liabilities;
                           and, in addition,

                  (ii)     indemnify and hold harmless the Vendor and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;

                  incurred by Vendor as a result of Vendor acting as the agent
                  of the Partnership and its partners pursuant to this Clause 5
                  including, without limitation, any and all Third Party costs
                  incurred by Vendor, Vendor's cost of insurance attributable to
                  such activities (provided however, the Vendor shall cause any
                  and all such insurance proceeds or rights thereto to be
                  contributed to the Partnership and to be retained in the
                  Partnership as of Closing Date such that the Partnership shall
                  receive the benefit of all such insurance proceeds, provided
                  further such insurance proceeds shall be excluded from the
                  Adjusted Working Capital portion of the Adjustment Report),
                  any claims of Third Parties and that portion of Vendor's costs
                  attributable to overhead associated with such activities in
                  accordance with the PASC Accounting Procedure, except any
                  Losses and Liabilities of Vendor and each of its directors,
                  officers, servants, agents and employees to the extent that
                  the same were a direct result of the gross negligence or
                  willful misconduct of the Vendor or an Affiliate of the
                  Vendor. An act or omission will not be regarded as gross
                  negligence or willful misconduct under this Clause 5 to the
                  extent that it was done or omitted to be done in accordance
                  with the Purchaser's written instructions or written
                  concurrence. The provisions of this Clause 5(d) shall survive
                  Closing on the Closing Date for the benefit of the Vendor.

         (e)      Notwithstanding anything contained in this Agreement, the
                  Parties acknowledge and agree that the Vendor and its
                  Affiliates, in their sole discretion, have or will enter into
                  various agreements with the Partnership on or prior to the
                  Closing Date as disclosed to Purchaser prior to the date of
                  execution of this Agreement to effect or document the prior
                  arrangements among Vendor and its Affiliates prior to the
                  Closing Date, and the Purchaser has been advised of the
                  general nature of these transactions.

         (f)      Provided Closing occurs, Vendor jointly and severally will:

                  (i)      be liable to Purchaser for its Losses and
                           Liabilities; and, in addition,

                  (ii)     indemnify and hold harmless the Purchaser and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;

                  incurred by Purchaser as a direct result of the gross
                  negligence or willful misconduct of the Vendor or an Affiliate
                  of the Vendor while Vendor acted as the agent of the
                  Partnership and its partners pursuant to this Clause 5. An act
                  or omission will not be


                                      -26-


                  regarded as gross negligence or willful misconduct under this
                  Clause 5 to the extent that it was done or omitted to be done
                  in accordance with the Purchaser's written instructions or
                  written concurrence.

6.       TITLE AND ENVIRONMENTAL REVIEW

         (a)      The Vendor, as agent for the Partnership, will, subject to the
                  Regulations, the Title and Operating Documents and the terms
                  and conditions of this Agreement, during the period following
                  the execution of this Agreement until the Closing Date:

                  (i)      make or cause to be made available for review, during
                           regular business hours, by the Purchaser, its
                           employees and agents (subject to their being covered
                           by a confidentiality agreement), the Vendor's and the
                           Partnership's records, files and documents directly
                           relating to the Assets, Office and Administrative
                           Assets, Nexen Seismic, Pipeline and the Securities,
                           for the purpose of the Purchaser's review of the
                           title of the Vendor to the Securities, Nexen Seismic,
                           Pipeline and the Office and Administrative Assets and
                           the Partnership's title to the Assets, including,
                           without limitation, the Title and Operating Documents
                           and any and all records pertaining to operating
                           revenues and expenses as are in the possession of the
                           Vendor or which the Vendor is entitled and provide,
                           if requested by the Purchaser, copies of same at
                           Purchaser's cost and expense;

                  (ii)     Subject to Clause 20, Purchaser (and its employees
                           and agents), at its sole cost, risk and expense, may,
                           upon prior notice to Vendor, inspect the Assets and
                           conduct an environmental assessment of the Assets
                           during regular business hours. If Purchaser
                           undertakes an environmental assessment, the scope of
                           the proposed assessment, including testing protocols,
                           must be acceptable to the Vendor, acting commercially
                           reasonable, prior to the commencement of the proposed
                           assessment. If Purchaser takes samples from the
                           Lands, Vendor shall require splitting of each sample
                           and Purchaser shall deliver such split sample to
                           Vendor. Purchaser shall, at its sole cost, provide
                           Vendor with copies of all final reports, results,
                           data and analyses of the site visit, inspections and
                           assessments within five (5) Business Days of
                           Purchaser's receipt of them. Notwithstanding anything
                           contained herein, the provisions of this Clause
                           6(a)(ii) (including the application of Clause 20)
                           shall survive Closing on the Closing Date for the
                           benefit of the Vendor;

         (b)      On or before five (5) Business Days prior to the Closing Date,
                  the Purchaser shall give the Vendor written notice of all
                  Title Defects and Environmental Defects which the Purchaser
                  does not waive. Such notice shall specify:

                  (i)      such Title Defects and Environmental Defects in
                           reasonable detail;

                  (ii)     the Assets directly affected thereby ("AFFECTED
                           ASSETS");

                  (iii)    in the case of Title Defects, the Purchaser's bona
                           fide estimate of the reduction in value of the
                           Affected Assets, broken down on an asset by asset
                           basis and a description on how such value was
                           determined;

                  (iv)     in the case of Environmental Defects, the Purchaser's
                           bona fide estimate of the aggregate cost of any
                           required remediation broken down on an itemized and
                           site by site basis; and

                  (v)      the Purchaser's requirements for the remedying
                           thereof.


                                      -27-


                  Notwithstanding the foregoing, the Purchaser shall keep the
                  Vendor informed on a regular basis as to any Title Defects and
                  Environmental Defects it discovers.

         (c)      Prior to the Closing Date, the Vendor shall provide notice to
                  the Purchaser as to whether it agrees with:

                  (i)      The existence of one or more Title Defects and
                           Environmental Defects; and

                  (ii)     The Purchaser's estimate of the reduction in the
                           value of the Affected Assets affected by such Title
                           Defects and the Purchaser's estimated cost of any
                           required remediation for such Environmental Defects,
                           as applicable, and if it does not agree, its reasons
                           regarding: (A) the non-existence of one or more Title
                           Defects and Environmental Defects; and (B) the
                           Purchaser's estimate of the reduction in value of the
                           Affected Assets affected by the Title Defects or its
                           estimated aggregate cost of remediating such
                           Environmental Defects, as applicable.

        [ INTENTIONALLY DELETED ]

         (e)      If the Vendor delivers a notice regarding Title Defects,
                  identified in the notice pursuant to Clause 6(b), pursuant to
                  Clause 6(c) disagreeing with the Purchaser, then the Vendor
                  and the Purchaser shall meet and use reasonable efforts to
                  agree on the validity of such Title Defect and the amount by
                  which the value of any Affected Assets has been reduced. In
                  determining any reduction in value of the Affected Assets and
                  corresponding reduction in the Purchase Price, it is the
                  intent of the Parties to include, when possible, only that
                  portion of the Assets adversely affected by the Uncured Title
                  Defect. If the Parties cannot mutually agree on the adjustment
                  to the Purchase Price for an Uncured Title Defect, then within
                  two (2) Business Days of notice of disagreement being given by


                                      -28-


                  the Vendor to the Purchaser pursuant to Clause 6(c), each
                  Party shall submit the determination of the reduction in the
                  value of the Assets adversely affected by the Uncured Title
                  Defects (which, in the case of the Purchaser, need not be, but
                  may not be higher than, the reduction in values of such
                  Affected Assets set forth in its notice delivered in
                  accordance with Clause 6(b) or which, in the case of the
                  Vendor, need not be, but may not be lower than, the reduction
                  in values of such Affected Assets set forth in its notice
                  delivered in accordance with Clause 6(c)), together with a
                  written statement as to how such reduction in values was
                  determined, to the Title Evaluator, together with written
                  instructions that:

                  (i)      the Title Evaluator, to the extent that it may be
                           necessary, may engage an independent petroleum
                           engineer to advise the Title Evaluator on the value
                           of an Uncured Title Defect;

                  (ii)     the Title Evaluator, in accordance with good legal,
                           engineering and evaluation practices, shall determine
                           the validity of the Uncured Title Defect and shall
                           select a value for each of the Affected Assets from
                           and based only upon the written statements and values
                           submitted by the Parties to the Title Evaluator,
                           provided that the Title Evaluator must select either
                           the Purchaser's or the Vendor's proposed value and
                           shall not be entitled to propose a compromise
                           settlement; and

                  (iii)    such evaluation and selection must be completed
                           within two (2) Business Days from the date of
                           submission.

                  The fees and other costs to be paid to the Title Evaluator in
                  respect to the services performed by it shall be paid in equal
                  shares by the Vendor and the Purchaser. If a Party fails to
                  provide a written statement of reduction in value to the Title
                  Evaluator together with its written instructions as set out
                  herein, then the Title Evaluator shall select the other
                  Party's determination of reduction in value and the
                  transaction shall proceed.

        [ INTENTIONALLY DELETED ]


                                      -29-


                          [ INTENTIONALLY DELETED ]

         (g)      If the Vendor delivers a notice regarding Environmental
                  Defects, identified in the notice pursuant to Clause 6(b),
                  pursuant to Clause 6(c) disagreeing with the Purchaser, then
                  for the purposes of the determination of the costs to
                  remediate any Environmental Defects for the purposes of Clause
                  6(f), the Vendor and the Purchaser shall meet and use
                  reasonable efforts to agree on the validity of the
                  Environmental Defect and the amount by which the value of any
                  Affected Assets has been reduced. If the Parties cannot
                  mutually agree on the adjustment to the Purchase Price for an
                  Uncured Environmental Defect, then within two (2) Business
                  Days of notice of disagreement being given by the Vendor to
                  the Purchaser pursuant to Clause 6(c), each Party shall submit
                  the determination of the costs (which, in the case of the
                  Purchaser may not be higher than, the costs set forth in its
                  notice delivered in accordance with Clause 6(b) or which, in
                  the case of the Vendor, may not be lower than, the costs set
                  forth in its notice delivered in accordance with Clause 6(c))
                  to remediate the Uncured Environmental Defects, together with
                  a written statement as to how such costs were determined, to
                  the Environmental Evaluator with written instructions that:

                  (i)      the Environmental Evaluator, in accordance with good
                           environmental assessment practices, shall determine
                           the validity of the Environmental Defect and shall
                           select a cost to remediate each Uncured Environmental
                           Defect, from and based only upon the written
                           statements and costs submitted by the Parties to the
                           Environmental Evaluator, provided that the
                           Environmental Evaluator must select either the
                           Purchaser's or the Vendor's proposed costs to
                           remediate and shall not be entitled to propose a
                           compromise settlement; and

                  (ii)     such evaluation and selection must be completed
                           within two (2) Business Days from the date of
                           submission.

                  The fees and other costs to be paid to the Environmental
                  Evaluator in respect of the services performed by it shall be
                  paid in equal shares by the Vendor and the Purchaser. If a
                  Party fails to give its written statement of proposed costs to
                  remediate to the Environmental Evaluator together with written
                  instructions as set out herein, then the Environmental
                  Evaluator shall select the other Party's proposed costs to
                  cure and the transaction shall proceed.

7.       THIRD PARTY RIGHTS AND CONSENTS

         (a)      Prior to and following Closing, at the request of the
                  Purchaser, Vendor shall use reasonable efforts to obtain and
                  deliver to the Purchaser all consents, permissions and
                  approvals by Third Parties and governmental and regulatory
                  authorities, which the Purchaser has (acting reasonably and in
                  good faith) identified as reasonably necessary and applicable
                  in connection with the transaction herein provided for.

         (b)      Within three (3) Business Days following the execution of this
                  Agreement by the Parties, the Vendor shall advise the
                  Purchaser which of the Assets are subject to Preferential
                  Rights. Within five (5) Business Days following the execution
                  of this Agreement by the Parties, the Purchaser shall advise
                  the Vendor in writing of its bona fide allocations of value
                  for such affected Assets. Provided that the Vendor is
                  satisfied that such allocations are bona fide and reasonable,
                  the Vendor shall comply with the applicable


                                      -30-


                  provisions of such Preferential Rights and shall serve notices
                  to the Third Parties (and Purchaser if applicable) holding
                  such Preferential Rights, such notices to be in a form
                  acceptable to the Purchaser acting reasonably, using the bona
                  fide allocations of the Purchaser. All such notices shall
                  include a request for a waiver of the Preferential Rights
                  held. In the event the Vendor is not satisfied that the
                  allocations of value made by the Purchaser are bona fide and
                  reasonable, the Vendor and Purchaser shall forthwith meet in
                  good faith to discuss the issue. If, after such a meeting, the
                  Vendor and Purchaser are not able to agree upon the value of
                  Assets affected by Preferential Rights, either the Vendor or
                  the Purchaser may, at its option, submit the determination of
                  such matter to arbitration pursuant to and in accordance with
                  Clause 16.

         (c)      The Vendor shall notify the Purchaser in writing forthwith
                  upon the exercise or waiver, on or before the Closing Date, if
                  any, of any Preferential Rights held by a Third Party,
                  provided however, the Parties acknowledge that the time period
                  in which Third Parties may elect to exercise certain
                  Preferential Rights will not expire until after the Closing
                  Date. The following shall apply with respect to Preferential
                  Rights:

                  (i)      Notwithstanding the exercise of a Preferential Right
                           prior to the Closing Date, the Parties shall proceed
                           with Closing on the Closing Date and the definition
                           of the Assets shall not be amended as a result of the
                           exercise of any Preferential Right;

                  (ii)     after Closing on the Closing Date, the Purchaser, as
                           agent for the Partnership, shall cause the
                           Partnership to forthwith assign and convey such
                           Assets in which a Preferential Right has been
                           exercised (whether by notice received before or after
                           the Closing Date), utilizing the values determined in
                           accordance with Clause 7(b), to such Third Party and
                           the cash proceeds shall be received and retained by
                           the Partnership after Closing; and

                 [ INTENTIONALLY DELETED ]

         (e)      Notwithstanding anything contained herein, Purchaser and the
                  Partnership jointly and severally will:

                  (i)      be liable to the Vendor for its Losses and
                           Liabilities; and, in addition,

                  (ii)     indemnify and hold harmless the Vendor and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;


                                      -31-


                  incurred by Vendor as a result of or in any way relating to
                  the failure of the Purchaser, as agent for the Partnership, to
                  subsequently convey any Assets subject to Preferential Rights
                  to any Third Party in accordance with Clause 7(c)(ii) and all
                  third party costs incurred by Vendor, any claims of Third
                  Parties, and any goods and services tax applicable thereto in
                  accordance with the Excise Tax Act (Canada). The provisions of
                  this Clause 7 shall survive the Closing Date for the benefit
                  of the Vendor.

8.       VENDOR'S REPRESENTATIONS

         (a)      The Vendor hereby represents, warrants and covenants to and
                  with the Purchaser except as set out in the Data Room
                  Materials or as otherwise disclosed to the Purchaser hereunder
                  that:

                  (i)      the Vendor and Subco are, and at the Closing Date
                           shall continue to be corporations or a general
                           partnership, as applicable, duly organized, validly
                           existing and in good standing under the laws of their
                           jurisdiction of incorporation or registration and the
                           laws of those jurisdictions in which the Vendor and
                           Subco are required to be registered in order to give
                           effect to this Agreement;

                  (ii)     the Vendor has all requisite power and authority to
                           enter into this Agreement and to perform the Vendor's
                           obligations under this Agreement;

                  (iii)    the execution and delivery of this Agreement and each
                           and every agreement or document to be executed and
                           delivered hereunder and the consummation of the
                           transactions contemplated herein will not violate,
                           nor be in conflict with, the constating documents or
                           bylaws of the Vendor, Subco or the Partnership, or
                           any provision of any agreement or instrument to which
                           the Vendor, Subco or the Partnership is a party or is
                           bound, or any judgment, decree, order, statute, rule
                           or regulation applicable to the Vendor, Subco or the
                           Partnership;

                  (iv)     this Agreement has been duly executed and delivered
                           by the Vendor and all documents required hereunder to
                           be executed and delivered by the Vendor shall have
                           been duly executed and delivered and this Agreement
                           does, and such documents will, constitute legal,
                           valid and binding obligations of the Vendor
                           enforceable in accordance with their respective
                           terms, subject to bankruptcy, insolvency, preference,
                           reorganization, moratorium and other laws affecting
                           creditors' rights generally, and the discretionary
                           nature of equitable remedies and defenses;

                  (v)      the Vendor has not incurred any obligation or
                           liability, contingent or otherwise, for brokers' or
                           finders' fees in respect of this transaction for
                           which the Purchaser shall have any obligation or
                           liability and Vendor's transaction costs, including
                           legal fees and broker's fees, if any, shall not be
                           borne by the Partnership or the Purchaser;

                  (vi)     at the Closing Date the Vendor will be the beneficial
                           owner of all of the Securities and Subco will be the
                           beneficial owner of a 0.1% Partnership Interest and
                           each has good title to the same, free and clear of
                           all security interests, equities, claims, options or
                           other encumbrances or voting trusts, proxies or other
                           interests of any nature whatsoever except those in
                           favor of the Purchaser and the partners of the
                           Partnership at the Closing Date will be NEXEN and
                           Subco;


                                      -32-


                  (vii)    the Partnership is, and at the Closing Date shall
                           continue to be, a general partnership duly organized,
                           validly existing and in good standing under the laws
                           of its jurisdiction of registration and the laws of
                           those jurisdictions in which the Partnership is
                           required to be registered in order to conduct its
                           business and own its assets and NEXEN is the managing
                           partner of the Partnership in accordance with the
                           Partnership Agreement;

                  (viii)   the execution and delivery of this Agreement and each
                           and every agreement or document to be executed and
                           delivered hereunder and the consummation of the
                           transactions contemplated herein will not violate,
                           nor be in conflict with, the Partnership Agreement or
                           any provision of any agreement or instrument to which
                           the Partnership is a party or is bound, or any
                           Regulation applicable to the Partnership;

                  (ix)     the Partnership and Subco have no subsidiaries;

                  (x)      Subco is not a "reporting issuer" under relevant
                           securities legislation or a "distributing
                           corporation" under relevant corporate legislation;

                  (xi)     the Purchaser has been provided a true, correct and
                           complete copy of the Partnership Agreement, together
                           with all amendments thereto, of the Partnership and
                           no resolutions have been proposed or passed to
                           further amend the foregoing;

                 [ INTENTIONALLY DELETED ]

                  (xiii)   the beneficial ownership of 100% of the Partnership
                           Interests of the Partnership on the Closing Date will
                           be owned and held as follows: NEXEN - 99.9% and Subco
                           - 0.1%;

                  (xiv)    other than Preferential Rights set forth in Schedule
                           "A" and the Purchaser's rights as provided in this
                           Agreement, there are no outstanding options, calls or
                           rights of any kind relating to or providing for the
                           purchase, delivery or transfer of any Securities,
                           Office and Administrative Assets, Pipeline, Nexen
                           Seismic or any of the Partnership's interest in the
                           Assets that are triggered as a result of this
                           Agreement;

                 [ INTENTIONALLY DELETED ]

                  (xvi)    the Partnership is a Canadian Partnership with the
                           meaning of that term as defined in the INCOME TAX ACT
                           (CANADA);

                  (xvii)   the Partnership is duly registered with the CANADA
                           REVENUE AGENCY and its GST registration number
                           [ INTENTIONALLY DELETED ];

                  (xviii)  Subco has filed on or prior to the Closing Date, or
                           will file after the Closing Date, at its sole cost,
                           all tax returns required to be filed on or prior to
                           the Closing Date with respect to any tax for any
                           period ending before the Closing Date and shall have
                           made complete and accurate disclosure in such tax
                           returns and materials accompanying them;


                                      -33-


                  (xix)    Subco and the Partnership have not provided any
                           waivers to CANADA REVENUE AGENCY or any other taxing
                           authority for any reason;

                  (xx)     prior to the Closing Date, no deficiency for any tax
                           has been proposed, asserted or assessed against Subco
                           or the Partnership and there are not outstanding tax
                           disputes, audits, proposed adjustments, notices of
                           objection or other appeals against Subco, or against
                           the Partnership;

                  (xxi)    prior to the Closing Date, the Vendor and Subco are
                           residents of Canada and are not non-residents of
                           Canada for the purposes of the INCOME TAX ACT
                           (CANADA);

                  (xxii)   all taxes and other assessments and levies which
                           Subco and the Partnership are required to withhold or
                           collect have been (and will be up to the Closing
                           Date) duly withheld and collected and paid over to
                           the proper government authorities;

                  (xxiii)  except for the Permitted Encumbrances, NEXEN owns a
                           100% interest in the Office and Administrative Assets
                           (subject to any applicable leases of equipment and
                           similar arrangements) and the Pipeline free and clear
                           of encumbrances, adverse claims and demands;

                  (xxiv)   the Vendor does not warrant its title to the Office
                           and Administrative Assets, Pipeline and Nexen Seismic
                           and the Partnership's title to the Assets but does
                           represent and warrant that at the Closing Date the
                           Partnership will have no assets other than the Assets
                           and any related working capital and balances due from
                           or to Affiliates and to its knowledge it has and
                           Subco and the Partnership have done no act or thing,
                           or are aware of no act or thing having been done,
                           whereby any of its title to the Office and
                           Administrative Assets, Pipeline and Nexen Seismic and
                           the Partnership's interest in and to the Assets may
                           be cancelled or terminated, nor has it or the
                           Partnership or Subco encumbered or alienated the
                           Assets, Pipeline, Nexen Seismic and Office and
                           Administrative Assets or any interest therein (except
                           for the Permitted Encumbrances), and to its knowledge
                           that the Assets Pipeline, Nexen Seismic and Office
                           and Administrative Assets are now and will be at the
                           Closing Date free and clear of all liens,
                           encumbrances, adverse claims, demands and royalties
                           granted by, through or under Partnership, Subco or
                           Vendor or their Affiliates, except for the Permitted
                           Encumbrances or as expressly set forth, in the Data
                           Room Materials;

                  (xxv)    it is not aware of, and has not received:

                           A.       any order or directive which relates to
                                    Environmental Defects, and which requires
                                    any work, repairs, construction, or capital
                                    expenditures, with respect to the Assets; or

                           B.       any demand or notice with respect to the
                                    breach of any environmental health, or
                                    safety law applicable to the Assets,
                                    including, without limitation, any
                                    regulations respecting the use, storage,
                                    treatment, transportation, or disposition of
                                    environmental contaminants;

                           except as has been disclosed in reasonable detail in
                           the Data Room Materials;

                  (xxvi)   subject at all times to the Vendor's other
                           representations and warranties made under this
                           Agreement, the Permitted Encumbrances, Title Defects
                           waived by the Purchaser under this Agreement and the
                           satisfaction of the obligations required to maintain
                           the Leases in good standing by the applicable
                           lessees, the Partnership


                                      -34-


                           may (upon Closing) enter into and upon, hold and
                           enjoy the Assets for the residue of their respective
                           terms and all renewals or extensions thereof for the
                           Partnership's own use and benefit without any lawful
                           interruption of or by the Vendor or any other person
                           whomsoever claiming or to claim by, through or under
                           the Vendor;

                  (xxvii)  to the Vendor's knowledge there are no outstanding
                           authorizations for expenditures, unit budgets and
                           mail ballots, pursuant to which expenditures will or
                           may be made in respect of the Assets, nor are there
                           any other financial commitments which are outstanding
                           or due or which hereafter may become due in respect
                           of the Assets or operations in respect thereof,
                           except those set out in Schedule "D" and those which
                           have been approved or deemed approved by Purchaser,
                           the Partnership or the Vendor and Subco pursuant to
                           Clause 5 of this Agreement;

                  (xxviii) to the Vendor's knowledge the Vendor, the Partnership
                           and Subco have not received notice of default
                           relating to the Assets or any of them, and to the
                           Vendor's knowledge all relevant deposits, rentals and
                           royalties have been paid within the applicable time
                           limits and in accordance with the applicable
                           Regulations and Title and Operating Documents, and
                           all obligations and covenants required to keep the
                           Leases in full force and effect have been performed
                           and observed except as has been disclosed
                           specifically in writing to the Purchaser prior to the
                           Closing Date or in the Data Room Materials;

                  (xxix)   to the Vendor's knowledge all ad valorem, property,
                           production, severance and similar taxes and
                           assessments based on or measured by the ownership of
                           property or the production of Petroleum Substances or
                           the receipt of proceeds therefrom payable in respect
                           of the Assets up to the Closing Date (including all
                           prior years) have been properly and fully paid and
                           discharged and there are no unpaid taxes and
                           assessments which are or could result in a lien or
                           charge on the Assets;

                  (xxx)    neither Vendor nor the Partnership nor Subco is a
                           party to any action, suit or other legal,
                           administrative or arbitration proceeding or
                           government investigation, actual or, to the Vendor's
                           knowledge, threatened, which pertains to Vendor's
                           title to the Securities, Pipeline, Nexen Seismic or
                           the Office and Administrative Assets or pertains to
                           the Assets or any part thereof except as set forth in
                           Schedule "H";

                  (xxxi)   to the Vendor's knowledge, the Wells have been
                           drilled and, if completed, completed and operated
                           and, if abandoned, have been abandoned, all in
                           accordance with good oil and gas field practices and
                           in compliance with all applicable Regulations and in
                           accordance with the terms and conditions of all
                           agreements relative thereto and to the Vendor's
                           knowledge the Tangibles have been constructed,
                           installed and maintained in accordance with good oil
                           and gas field practices and are in good operating
                           condition, subject to reasonable wear and tear;

                  (xxxii)  the Vendor, Subco or the Partnership have not
                           received notice of and are not otherwise aware of any
                           change or proposed change in the production
                           allowables for any of the Wells producing Petroleum
                           Substances or any other wells from which production
                           of Petroleum Substances is allocated to the Lands;


                                      -35-


                  (xxxiii) to the Vendor's knowledge it has made available to
                           the Purchaser all information within its possession,
                           and has not knowingly withheld any such information
                           from Purchaser, relevant to Environmental Defects;

                  (xxxiv)  except for the agreements set forth in Schedule "E",
                           the Assets do not include and the Partnership and
                           Subco are not obligated or bound by any contracts or
                           agreements for:

                           A.       the sale or delivery of Petroleum Substances
                                    allocable to the Petroleum and Natural Gas
                                    Rights that cannot be terminated on notice
                                    of thirty one (31) days or less without
                                    penalty;

                           B.       gas balancing or similar provision;

                           C.       the sale or delivery of Petroleum Substances
                                    allocable to any of the Petroleum and
                                    Natural Gas Rights without in due course
                                    receiving or being entitled to retain full
                                    payment therefor at the full price which
                                    would otherwise be applicable thereunder;

                           D.       the delivery of gas or the reimbursement to
                                    any person of an amount on account of
                                    payments previously made in respect of
                                    quantities of Petroleum Substances which
                                    were not previously delivered;

                           E.       agreements for the transportation,
                                    processing or disposal of the Petroleum
                                    Substances or any of them or substances
                                    produced in connection with the Petroleum
                                    Substances or any of them, agreements for
                                    the contract operation by a Third Party of
                                    the Assets or any of them, and agreements to
                                    provide transportation, processing or
                                    disposal capacity or service to any Third
                                    Party; or

                           F.       Futures Transactions;

                  (xxxv)   the authorized share capital of Subco consists of an
                           unlimited number of Class A common shares and an
                           unlimited number of Class B preferred shares of
                           which, as of the Closing Date, only two (2) Class A
                           common shares will be validly issued and outstanding
                           and all of which will be registered in the name of
                           CNYL;

                  (xxxvi)  as of the Closing Date no Person shall have any
                           rights capable of being converted into, exchanged for
                           or exercised for shares or other securities of Subco
                           ("Share Right") or any other agreement, option or
                           privilege (whether pre-emptive, contractual or
                           otherwise) capable of becoming a Share Right and the
                           execution and delivery of this Agreement shall not
                           give any Person other than the Purchaser any Share
                           Right;

                  (xxxvii) except as it relates to transactions or matters
                           arising from or contemplated in this Agreement, the
                           minute book and share ledger of Subco will be true
                           and correct in all material respects and such minute
                           books shall contain copies of all meetings of the
                           directors and shareholders of Subco and all
                           resolutions by consent (if any) of the directors and
                           shareholders;

                  (xxxviii)except for:

                           A.       Current Liabilities;


                                      -36-


                           B.       Nexen Receivables;

                           C.       liabilities as a result of transactions
                                    contemplated by this Agreement;

                           D.       liabilities relating to the accounting for
                                    future income taxes and asset retirement
                                    obligations;

                           E.       liabilities under the Title and Operating
                                    Documents, the Regulations (excluding the
                                    Tax Act) and the Permitted Encumbrances; and

                           F.       liabilities which will be satisfied,
                                    discharged or released or assumed by NEXEN
                                    pursuant to the Operations Agreement dated
                                    January 1, 2005 between NEXEN and the
                                    Partnership, as at the Closing Date;

                           the Partnership and Subco as of Closing will have no
                           liabilities;

                  (xxxix)  the Partnership and Subco have not received notice
                           that the technology owned or used by Subco or the
                           Partnership infringes upon any patents, trade marks,
                           trade secrets or copyrights owned by other Persons;

                  (xl)     prior to the Closing Date, the Vendor has provided to
                           the Purchaser a complete and correct list of all bank
                           accounts and safety deposit boxes maintained by Subco
                           and the Partnership;

                  (xli)    to the knowledge of the Vendor, there are no area of
                           mutual interest or area of exclusion provisions
                           applicable to and binding upon the Partnership or
                           Subco except as disclosed in Schedule "A" attached
                           hereto;

                 [ INTENTIONALLY DELETED ]

                  (xliii)  except as provided pursuant to the transactions
                           referred to in Clause 5(e), no Person now holds, or
                           at the Closing Date will hold, any power of attorney
                           from the Partnership or Subco other than any power of
                           attorney granted pursuant to the Partnership
                           Agreement;

                  (xliv)   except as provided pursuant to the transactions
                           referred to in Clause 5(e), under this Agreement or
                           the Partnership Agreement, neither the Partnership
                           nor Subco has guaranteed, endorsed, assumed or
                           indemnified, contingently or otherwise, the
                           obligations or indebtedness of any Person except, in
                           the ordinary course of the oil and gas business,
                           pursuant to the Title and Operating Documents; and

                  (xlv)    no material tangible depreciable property, inventory
                           or equipment that would otherwise form part of the
                           Tangibles or Office and Administrative Assets has
                           been removed from its location since the Effective
                           Date.

         (b)      The Vendor makes no representations, warranties or covenants
                  to the Purchaser except those enumerated in Subclause 8(a).
                  Vendor disclaims any liability and responsibility for any
                  representation or warranty which may have been made or alleged
                  to have been made and which is contained in any instrument or
                  document relative hereto or to the transactions herein
                  provided for, or contained in any statement or information
                  made or communicated (orally or in writing) to Purchaser
                  including, without limitation of the generality of the
                  foregoing, any opinion, information or advice which may have
                  been provided to Purchaser by any officer, partner,
                  shareholder, director, employee, agent,


                                      -37-


                  consultant or representative of Vendor. Except and to the
                  extent provided in Subclause 8(a), the Vendor does not warrant
                  the Partnership's title to the Assets, the Vendor's title to
                  the Securities or the Vendor's title to the Nexen Seismic,
                  Pipeline and Office and Administrative Assets or make
                  representations, warranties or covenants with respect to:

                  (i)      the quantity, quality or recoverability of Petroleum
                           Substances respecting the Lands;

                  (ii)     any information or data supplied by Vendor pursuant
                           hereto;

                  (iii)    any estimates of the value of the Securities, Nexen
                           Seismic, Pipeline and Office and Administrative
                           Assets or the Assets or the revenues applicable to
                           future production from the Lands;

                  (iv)     any engineering, geological or other interpretations
                           or economic evaluations respecting the Assets;

                  (v)      the rates of production of Petroleum Substances from
                           the Lands;

                  (vi)     the quality, condition or serviceability of the
                           Assets and the Nexen Seismic, Pipeline and Office and
                           Administrative Assets;

                  (vii)    the fitness or suitability of the Assets for any
                           purpose or the merchantability of the Assets and the
                           Nexen Seismic, Pipeline and Office and Administrative
                           Assets; or

                  (viii)   the ability or assurance that the Partnership will
                           continue to serve as operator of the Assets after
                           Closing or that the Purchaser will be able to assume
                           and/or serve as operator of any of the Assets.

                  Without restricting the generality of the foregoing, the
                  Purchaser acknowledges that it has made its own independent
                  investigation, analysis, evaluation and inspection of the
                  Vendor's interest in and to the Securities, Nexen Seismic,
                  Pipeline and Office and Administrative Assets and the
                  Partnership's interest in and to the Assets and the state and
                  condition thereof and that it has relied solely on such
                  investigation, analysis, evaluation and inspection as to its
                  assessment of the condition, quantum and value of the
                  Securities, Nexen Seismic, Pipeline and Office and
                  Administrative Assets and the Assets.

         (c)      Except with respect to the representations, warranties and
                  covenants in Subclause 8(a) or in the event of fraud, the
                  Purchaser forever releases and discharges the Vendor, its
                  Affiliates and its directors, officers, servants, agents and
                  employees from any claims and all liability to the Purchaser
                  or the Purchaser's assigns and successors, as a result of, the
                  use of, or reliance upon advice, information or materials
                  pertaining to the Securities, Nexen Seismic, Pipeline, Office
                  and Administrative Assets and the Assets which were delivered
                  or made available to the Purchaser by the Vendor, its
                  Affiliates or its directors, officers, servants, agents or
                  employees prior to or pursuant to this Agreement, including,
                  without limitation, any evaluations, projections, reports and
                  interpretive or non-factual materials prepared by or for the
                  Vendor, or otherwise in the Vendor's possession.


                                      -38-


9.       PURCHASER'S REPRESENTATIONS

         (a)      The Purchaser hereby represents, warrants and covenants to and
                  with the Vendor that:

                  (i)      the Purchaser is, and at the Closing Date shall
                           continue to be, a trust duly organized and validly
                           existing under the laws of Alberta and the laws of
                           those jurisdictions in which it is required to be
                           qualified in order for it to acquire and own the
                           Securities, Nexen Seismic, Pipeline and Office and
                           Administrative Assets;

                  (ii)     the Purchaser has all requisite power and authority
                           to enter into this Agreement and to purchase and pay
                           for the Securities, Nexen Seismic, Pipeline and
                           Office and Administrative Assets on the terms
                           described herein and to perform its other obligations
                           under this Agreement and has taken all action
                           necessary to authorize the execution, delivery and
                           performance of this Agreement and the purchase of the
                           Securities, Nexen Seismic, Pipeline and Office and
                           Administrative Assets in accordance with this
                           Agreement;

                  (iii)    the execution and delivery of this Agreement and each
                           and every agreement or document to be executed and
                           delivered hereunder and the consummation of the
                           transactions contemplated herein will not violate,
                           nor be in conflict with, any provision of any trust
                           indenture or other governing agreement of the
                           Purchaser, or any judgment, decree, order, statute,
                           rule or regulation applicable to the Purchaser;

                  (iv)     this Agreement has been duly executed and delivered
                           by the Purchaser and all documents required hereunder
                           to be executed and delivered by the Purchaser shall
                           have been duly executed and delivered and this
                           Agreement does, and such documents will, constitute
                           legal, valid and binding obligations of the Purchaser
                           enforceable in accordance with their respective
                           terms, subject to bankruptcy, insolvency, preference,
                           reorganization, moratorium and other laws affecting
                           creditors' rights generally, and the discretionary
                           nature of equitable remedies and defenses;

                  (v)      the Purchaser has not incurred any obligation or
                           liability, contingent or otherwise, for brokers' or
                           finders' fees in respect of this transaction for
                           which the Vendor shall have any obligation or
                           liability;

                  (vi)     the Purchaser shall comply with the provisions of the
                           INVESTMENT CANADA ACT (Canada) and the COMPETITION
                           ACT (Canada), if applicable;

                  (vii)    there are no necessary regulatory approvals or
                           rulings required to be obtained by the Purchaser to
                           permit the transactions contemplated herein to be
                           completed except approvals and rulings, if any, under
                           the COMPETITION ACT (Canada);

                  (viii)   the Purchaser shall comply with all applicable
                           statutes, laws and Regulations required for the
                           approval of all Well license transfers from the
                           Vendor and/or the Partnership to the Purchaser; and

                  (ix)     The Purchaser is acquiring the Securities, Nexen
                           Seismic, Pipeline and Office and Administrative
                           Assets on behalf of itself and its Affiliates and not
                           as agent on behalf of any non-Affiliate Third Party.


                                      -39-


10.      NO MERGER AND SURVIVAL

         (a)      The covenants, representations and warranties set forth in
                  Clauses 8 and 9 shall be deemed to apply to all assignments,
                  conveyances, transfers and documents conveying any of the
                  Securities and the Assets, if applicable, and Nexen Seismic,
                  Pipeline and Office and Administrative Assets from the Vendor
                  to the Purchaser and/or the Partnership and there shall not be
                  any merger of any covenant, representation or warranty in such
                  assignments, transfers or documents notwithstanding any rule
                  of law, equity or statute to the contrary and all such rules
                  are hereby waived.

         (b)      Notwithstanding anything to the contrary herein expressed or
                  implied but subject to Clause 11(d), it is expressly agreed
                  and understood that the covenants, representations and
                  warranties set forth in Clauses 8 and 9 are true on the date
                  hereof and shall be repeated at the Closing Date as being true
                  in all material respects at the Closing Date and,
                  notwithstanding the Closing or deliveries of covenants,
                  representations and warranties in any other agreements at
                  Closing or prior or subsequent thereto or investigations by
                  the Parties or their counsel, the covenants, representations
                  and warranties set forth in Clauses 8 and 9 shall survive
                  Closing for the benefit of the Parties for a period of twelve
                  (12) months from the Closing Date, PROVIDED HOWEVER, no claim
                  or action shall be commenced with respect to a breach of any
                  such representation, warranty or covenant, unless, within such
                  twelve (12) month period, written notice specifying such
                  breach in reasonable detail has been provided to the Party
                  which made such representation, warranty or covenant.

         (c)      A Party hereto shall have no remedy or cause of action for a
                  misstatement or inaccuracy of a representation or warranty
                  actually known to the Party, as at the Closing Date.

         (d)      The representations and warranties set forth in Clauses 8 and
                  9 are made for the exclusive benefit of the Purchaser and the
                  Vendor, as the case may be, and may not be the subject of any
                  rights of subrogation in favor of any other person. No Party
                  may transfer such representations and warranties without the
                  written consent of the Party providing the representation
                  and/or warranty.

11.      INDEMNITIES

         (a)      Subject to Clauses 2(f), 5 and 11 herein (including, without
                  limitation, Clauses 11(c) and 11(d)) and provided that Closing
                  has occurred, the Vendor shall:

                  (i)      be liable to the Purchaser for its Losses and
                           Liabilities; and, in addition

                  (ii)     indemnify and hold harmless the Purchaser and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;

                  as a direct result of: (A) any act, omission, circumstance or
                  other matter or thing arising out of, resulting from,
                  attributable to or connected with Vendor's breach,
                  misstatement or inaccuracy of any of the representations and
                  warranties of the Vendor under this Agreement; and (B) any
                  amounts payable by Subco in respect of the income or loss for
                  income tax purposes of Subco, pursuant to and in accordance
                  with the Tax Act, for any taxation year of Subco that ends
                  prior to the Closing Date except for any current liabilities
                  of Subco which are taken into account in the Adjustment Report
                  pursuant to Clause 3(a)(vi), except any Losses and Liabilities
                  to the extent they are caused by a breach of the Purchaser's
                  representations or warranties under Clause 9 or by the gross
                  negligence or willful misconduct of the Purchaser, or any of
                  its directors, officers, agents, employees or assigns. The
                  indemnity granted by the Vendor herein, however,


                                      -40-


                  does not provide either an extension of any representation,
                  warranty or covenant contained in Clause 8 or an additional
                  remedy with respect to the Vendor's breach of such
                  representation, warranty or covenant

         (b)      Subject to Clauses 2(f), 5 and 11 herein (including, without
                  limitation, Clause 11(d)) and provided that Closing has
                  occurred, the Purchaser shall:

                  (i)      be liable to the Vendor for its Losses and
                           Liabilities; and, in addition

                  (ii)     indemnify and hold harmless the Vendor and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;

                  as a direct result of any act, omission, circumstance or other
                  matter or thing arising out of, resulting from, attributable
                  to or connected with:

                  (iii)    all rights, duties, benefits, obligations or
                           liabilities of Subco and the Partnership whatsoever;

                  (iv)     the Assets, Nexen Seismic, Pipeline and Office and
                           Administrative Assets; and

                  (v)      any amounts payable in respect of the income or loss
                           for income tax purposes, and all other amounts that
                           are allocable for the purposes of the Tax Act, of the
                           Partnership, pursuant to and in accordance with the
                           Tax Act, for any fiscal period of the Partnership
                           that ends on or includes or ends after the Closing
                           Date;

                  occurring or accruing subsequent to the Closing Date, except
                  any Losses and Liabilities insofar as they are caused by the
                  gross negligence or willful misconduct of the Vendor, Subco or
                  the Partnership or their directors, officers, servants,
                  agents, employees or assigns.

         (c)      Except as set forth in Clause 8, the Purchaser is not relying
                  upon any representation or warranty of the Vendor as to the
                  condition, environmental or otherwise, of the Assets, and
                  acknowledges that it is buying the Securities (which includes
                  ownership of the Assets), Nexen Seismic, Pipeline and Office
                  and Administrative Assets on an "as is" basis, as of the
                  Closing Date. Provided that Closing has occurred, the
                  Purchaser further agrees that, notwithstanding anything
                  contained in this Agreement, as of the Closing Date, it shall:

                  (i)      be solely liable and responsible to the Vendor for
                           its Losses and Liabilities; and, in addition

                  (ii)     indemnify and hold harmless the Vendor and each of
                           its directors, officers, servants, agents and
                           employees from and against all Losses and
                           Liabilities;

                  as a direct result of any matter or thing arising out of,
                  resulting from, attributable to or connected with any
                  Abandonment and Reclamation Obligations, Environmental
                  Liabilities, Environmental Defects, Uncured Environmental
                  Defects, environmental matters or any other environmental
                  liabilities whatsoever of any nature or kind and whenever
                  occurring, pertaining to the Assets, or any of them. Once
                  Closing has occurred, the Purchaser shall be solely
                  responsible for all Abandonment and Reclamation Obligations,
                  Environmental Liabilities, Environmental Defects, Uncured
                  Environmental Defects, environmental matters or any other
                  environmental liabilities whatsoever of any nature or kind and
                  whenever occurring, respecting the Assets, Pipeline and Office
                  and Administrative Assets, the abandonment of the Wells and
                  the Tangibles and the


                                      -41-


                  reclamation of the Assets, Pipeline and Office and
                  Administrative Assets as between the Vendor and the Purchaser,
                  and hereby releases the Vendor from any claims the Purchaser
                  may have against the Vendor with respect to all such
                  liabilities and responsibilities. Nothing in this Clause,
                  however, shall operate either to limit any representation,
                  warranty or covenant made by the Vendor pursuant to Clause 8
                  or to affect the Purchaser's right to make a claim against the
                  Vendor for the breach of such a representation, warranty or
                  covenant in accordance with Clause 10.

        [ INTENTIONALLY DELETED ]

         (e)      Any Party seeking indemnification shall give reasonably prompt
                  notice thereof to the Party from whom indemnification is
                  sought. The Party from whom indemnification is sought shall
                  have the sole right to conduct, settle or otherwise dispose of
                  any legal action in respect of which indemnification is sought
                  in any manner it deems appropriate without the consent of the
                  Party seeking indemnification but only if it has agreed that
                  the matters in the action are indemnified pursuant to Clauses
                  11(a), (b) and (c). If the Party from


                                      -42-


                  whom indemnification is sought pays the indemnified amount to
                  the other Party seeking indemnification, the paying Party
                  shall not be responsible for any costs relating to legal and
                  other professional fees and disbursements incurred after such
                  payment.

         (f)      The provisions of this Clause 11 shall survive Closing on the
                  Closing Date for the benefit of the Vendor and Purchaser.

12.      VENDOR'S CLOSING CONDITIONS

         (a)      The obligation of the Vendor to complete the sale of the
                  Securities, Nexen Seismic, Pipeline and Office and
                  Administrative Assets to the Purchaser pursuant to this
                  Agreement is subject to the satisfaction at or prior to the
                  Closing Date of the following conditions precedent:

                  (i)      all representations and warranties of the Purchaser
                           contained in this Agreement shall be true in all
                           material respects at and as of the date hereof and
                           the Closing Date, as applicable, and the Purchaser
                           shall have provided a certificate of an officer
                           attesting thereto;

                  (ii)     the Purchaser shall have performed and satisfied all
                           agreements and obligations required by this Agreement
                           to be performed and satisfied by the Purchaser at or
                           prior to the Closing Date and the Purchaser shall
                           have provided a certificate of an officer attesting
                           thereto;

                  (iii)    all consents, orders, regulations, approvals and
                           certificates, including regulatory, judicial and
                           other approvals required by the Regulations
                           (including COMPETITION ACT (Canada) Approval), as may
                           be necessary to enable the Parties to complete the
                           transactions contemplated in this Agreement shall
                           have been obtained by the Parties on or before
                           Closing in form and substance satisfactory to the
                           Parties, acting reasonably, or where not obtained all
                           applicable waiting periods for the obtaining of such
                           approvals and orders will have expired such that the
                           transactions contemplated in this Agreement may
                           lawfully proceed without such approvals and orders
                           being required, which determination shall be made
                           based on an opinion of counsel;

                  (iv)     the Purchaser shall have tendered to the Vendor in
                           the form stipulated herein the total amount payable
                           by the Purchaser to the Vendor pursuant hereto; and

                  (v)      no suit, action or other proceeding shall, at
                           Closing, be pending against the Vendor, the Purchaser
                           or the Partnership before any court or governmental
                           agency seeking to retain, prohibit, obtain damages or
                           other relief in connection with the consummation of
                           the transactions contemplated by this Agreement which
                           would materially and adversely affect the Vendor, the
                           Purchaser or the Partnership.

                  The foregoing conditions shall be for the benefit of the
                  Vendor and may, without prejudice to any of the rights of the
                  Vendor hereunder (including reliance upon or enforcement of
                  the warranties or covenants which are preserved dealing with
                  or similar to the condition waived) be waived by the Vendor in
                  writing, in whole or in part, at any time. In case any of the
                  said conditions shall not be complied with, or waived by the
                  Vendor, at or before the Closing Date, the Vendor may rescind
                  or terminate this Agreement by written notice to the
                  Purchaser.

13.      PURCHASER'S CLOSING CONDITIONS


                                      -43-


         (a)      The obligation of the Purchaser to complete the purchase of
                  the Securities, Nexen Seismic, Pipeline and Office and
                  Administrative Assets from the Vendor pursuant to this
                  Agreement is subject to the satisfaction at or prior to the
                  Closing Date of the following conditions precedent:

                  (i)      all representations and warranties of the Vendor
                           contained in this Agreement shall be true in all
                           material respects at and as of the date hereof and at
                           the Closing Date, as applicable, and the Vendor shall
                           have provided a certificate of an officer attesting
                           thereto;

                  (ii)     the Vendor shall have performed and satisfied all
                           agreements and obligations required by this Agreement
                           to be performed and satisfied by the Vendor at or
                           prior to the Closing Date and the Vendor shall have
                           provided a certificate of an officer attesting
                           thereto;

                  (iii)    subject to the obligations contained in Clause 4, the
                           Vendor shall have tendered to the Purchaser documents
                           and materials satisfying the requirements of Clause 4
                           hereof;

                  (iv)     all consents, orders, regulations, approvals and
                           certificates, including regulatory, judicial and
                           other approvals required by the Regulations
                           (including COMPETITION ACT (Canada) Approval), as may
                           be necessary to enable the Parties to complete the
                           transactions contemplated in this Agreement shall
                           have been obtained by the Parties on or before
                           Closing in form and substance satisfactory to the
                           Parties, acting reasonably, or where not obtained all
                           applicable waiting periods for the obtaining of such
                           approvals and orders will have expired such that the
                           transactions contemplated in this Agreement may
                           lawfully proceed without such approvals and orders
                           being required, which determination shall be made
                           based on an opinion of counsel;

                  (v)      no suit, action or other proceeding shall, at
                           Closing, be pending against the Vendor, the Purchaser
                           or the Partnership before any court or governmental
                           agency seeking to retain, prohibit, obtain damages or
                           other relief in connection with the consummation of
                           the transactions contemplated by this Agreement which
                           would materially and adversely affect the Vendor, the
                           Purchaser or the Partnership;

                  (vi)     except as provided for in this Agreement or consented
                           to by the Purchaser, no substantial damage to or
                           material adverse alteration in or to the Assets or
                           the Pipeline which have occurred between the date
                           hereof and the Closing Date which, in the Purchaser's
                           opinion, acting reasonably and in good faith, would
                           materially and adversely affect the value of the
                           Assets excluding all decreases in the value of the
                           Assets or the Pipeline pursuant to Clauses 6 and 7 or
                           as otherwise disclosed to the Purchaser in the Data
                           Room Materials; but for this purpose, standard
                           production practices or a decline in the value or
                           valuation of the Petroleum Substances shall not be
                           events which fall under the auspices of this
                           condition precedent;

                  (vii)    all requisite approvals of regulatory bodies relative
                           to the transactions herein provided for shall have
                           been obtained; and

                  (viii)   all transactions between Vendor and its Affiliates as
                           referred to in Clause 5(e) have been or will be
                           completed on or prior to the Closing Date.


                                      -44-


                  The foregoing conditions shall be for the benefit of the
                  Purchaser and may, without prejudice to any of the rights of
                  the Purchaser hereunder (including reliance upon or
                  enforcement of warranties or covenants which are preserved
                  dealing with or similar to the condition or conditions waived)
                  be waived by the Purchaser in writing, in whole or in part, at
                  any time, provided the Purchaser may not waive the existence
                  and operation of any Preferential Right to purchase any of the
                  Assets. In case any of the said conditions shall not be
                  complied with, or waived by the Purchaser, at or before the
                  Closing Date, the Purchaser may rescind and terminate this
                  Agreement by written notice to the Vendor.

14.      TERMINATION

         Subject to Clauses 2(h) and 15, in the event that this Agreement is
         terminated prior to Closing pursuant to any of Clauses 6, 7, 12, 13 or
         15, each Party hereto shall be released from all obligations hereunder
         and each Party hereto shall take all reasonable action to return each
         of the other Parties hereto to the position relative to the Securities,
         Nexen Seismic, Pipeline and Office and Administrative Assets and the
         Assets which such Party occupied prior to the execution hereof, it
         being understood that the Vendor and the Purchaser will each bear all
         costs incurred by it prior to such termination.

15.      DEFAULT

         (a)      If a Party (the "DEFAULTING PARTY") fails to comply with an
                  obligation under this Agreement and Closing does not occur as
                  a result, the other Party (the "INJURED PARTY") may, by notice
                  to the Defaulting Party, elect:

                  (i)      to continue to treat this Agreement as binding and
                           enforceable; or

                  (ii)     to treat this Agreement as terminated by reason of
                           the non-fulfillment of the Defaulting Party's
                           obligations and, subject to Clause 16, provided that:

                           A.       the Deposit and interest accrued thereon
                                    will be returned to the Purchaser if the
                                    Purchaser is the Injured Party and the
                                    Purchaser may pursue a claim for damages
                                    against the Vendor; or

                           B.       if the Defaulting Party is the Purchaser,
                                    the Deposit and the interest accrued thereon
                                    will be retained by the Vendor in full
                                    settlement of all damages suffered by Vendor
                                    and to compensate the Vendor for expenses
                                    incurred in connection with the transaction
                                    contemplated herein and the delay or
                                    permanent impairment caused to the Vendor's
                                    efforts to sell the Securities, the
                                    Pipeline, the Nexen Seismic and the Office
                                    and Administrative Assets. For clarity, the
                                    Vendor's retention of the Deposit is a
                                    genuine pre-estimate of liquidated damages
                                    suffered and not a penalty.

                  Notwithstanding anything contained herein, the Injured Party
                  will be deemed to treat this Agreement as binding and
                  enforceable until it elects, by notice to the Defaulting
                  Party, to apply Clause 15(a)(ii).

         (b)      Any amount owing to a Party by the other Party hereunder after
                  Closing and remaining unpaid will bear interest at the Prime
                  Rate, from the day that the amount was due to be paid until
                  the day it is paid, regardless of whether the Party has given
                  the other Party prior notice of the accrual of interest
                  hereunder.


                                      -45-


16.      DISPUTE RESOLUTION

         (a)      The Parties will attempt to resolve any dispute arising
                  hereunder through consultation and negotiation in good faith.
                  If those attempts fail, the Parties shall, refer the dispute
                  to binding arbitration. Any such arbitration, and any other
                  arbitration the Parties may agree to conduct hereunder, will
                  be conducted under the Commercial Arbitration Rules of The
                  Canadian Foundation for Dispute Resolution.

         (b)      All limitation periods respecting the commencement of an
                  action will be stayed during the period that the Parties are
                  attempting to resolve a dispute under Clause 16(a) or
                  otherwise under this Agreement. A Party may, at any time it
                  believes it necessary to protect its interest during that
                  period, seek interim or provisional relief, in form of a
                  temporary restraining order, preliminary injunction or other
                  interim equitable relief concerning a dispute under this
                  Agreement, notwithstanding anything to the contrary in this
                  Clause.

         (c)      Notwithstanding anything contained herein, the provisions of
                  this Clause 16 shall not apply to any disputes under Clause 6.

17.      EMPLOYMENT MATTERS

        [ INTENTIONALLY DELETED ]


                                      -46-


        [ INTENTIONALLY DELETED ]

18.      PROTECTION OF PERSONAL INFORMATION

         The following shall apply with respect to privacy and the collection,
         use and disclosure of personal information:

         (a)      For the purposes of this Clause 18, the following definitions
                  shall apply:

                  (i)      "APPLICABLE LAW" means, in relation to any person,
                           transaction or event, all applicable provisions of
                           laws, statutes, rules, regulations, official
                           directives and orders of and the terms of all
                           judgments, orders and decrees issued by any
                           authorized authority by which such person is bound or
                           having application to the transaction or event in
                           question, including applicable privacy laws;

                  (ii)     "APPLICABLE PRIVACY LAWS" means any and all
                           applicable laws relating to privacy and the
                           collection, use and disclosure of Personal
                           Information in all applicable jurisdictions,
                           including but not limited to the PERSONAL INFORMATION
                           PROTECTION AND ELECTRONIC DOCUMENTS ACT (CANADA)
                           and/or any comparable provincial law including the
                           PERSONAL INFORMATION PROTECTION ACT (ALBERTA);

                  (iii)    "AUTHORIZED AUTHORITY" means, in relation to any
                           person, transaction or event, any: (a) federal,
                           provincial, municipal or local governmental body
                           (whether administrative, legislative, executive or
                           otherwise), both domestic and foreign; (b) agency,
                           authority, commission, instrumentality, regulatory
                           body, court, central bank or other entity exercising
                           executive, legislative, judicial, taxing, regulatory
                           or administrative powers or functions of or
                           pertaining to government; (c) court, arbitrator,
                           commission or body exercising judicial,
                           quasi-judicial, administrative or similar functions;
                           and (d) other body or entity created under the
                           authority of or otherwise subject to the jurisdiction
                           of any of the foregoing, including any stock or other
                           securities exchange, in each case having jurisdiction
                           over such person, transaction or event; and

                  (iv)     "PERSONAL INFORMATION" means information about an
                           individual transferred to


                                      -47-


                           one party by the other in accordance with this
                           Agreement and/or as a condition of the Transaction.

         (b)      The Parties acknowledge that they are responsible for
                  compliance at all times with applicable privacy laws which
                  govern the collection, use and disclosure of Personal
                  Information acquired by or disclosed to either party pursuant
                  to or in connection with this Agreement (the "Disclosed
                  Personal Information").

         (c)      Prior to Closing, neither party shall use the Disclosed
                  Personal Information for any purposes other than those related
                  to the performance of this Agreement and the completion of the
                  transaction contemplated herein. The Purchaser undertakes
                  after Closing to only use the Personal Information in
                  accordance with the purpose for which the Personal Information
                  was originally collected and to obtain consents where required
                  by applicable privacy Regulations prior to using or disclosing
                  the Personal Information.

         (d)      Each party acknowledges and confirms that the disclosure of
                  Personal Information is necessary for the purposes of this
                  Agreement, and that the disclosure of Personal Information
                  relates solely to the carrying on of the business and the
                  completion of the transaction contemplated herein.

         (e)      Each party acknowledges and confirms that it has and shall
                  continue to employ appropriate technology and procedures in
                  accordance with applicable law to prevent accidental loss or
                  corruption of the Disclosed Personal Information, unauthorized
                  input or access to the Disclosed Personal Information, or
                  unauthorized or unlawful collection, storage, disclosure,
                  recording, copying, alteration, removal, deletion, use or
                  other processing of such Disclosed Personal Information.

         (f)      Each party shall at all times keep strictly confidential all
                  Disclosed Personal Information provided to it, and shall
                  instruct those employees or advisors responsible for
                  processing such Disclosed Personal Information to protect the
                  confidentiality of such information in a manner consistent
                  with the parties' obligations hereunder. Each party shall
                  ensure that access to the Disclosed Personal Information shall
                  be restricted to those employees or advisors of the respective
                  party who have a bona fide need to access to such information
                  in order to complete the transaction contemplated herein.

         (g)      Each party shall promptly notify the other party of all
                  inquiries, complaints, requests for access, and claims of
                  which the party is made aware in connection with the Disclosed
                  Personal Information. The parties shall fully co-operate with
                  one another, with the persons to whom the Personal Information
                  relates, and any authorized authority charged with enforcement
                  of applicable privacy laws, in responding to such inquiries,
                  complaints, requests for access, and claims.

         (h)      If Closing does not occur, the Purchaser shall return to the
                  Vendor, and destroy all copies of any Personal Information
                  disclosed to the Purchaser in connection with this Agreement.

         (i)      On or before Closing, the Purchaser shall return all Personal
                  Information acquired by it in connection with this Agreement,
                  or copies thereof, relating to any Field Employees who are not
                  offered employment by the Purchaser.

         (j)      The provisions of this Clause 18 shall survive the Closing
                  Date.


                                      -48-


19.      POST-CLOSING OBLIGATIONS

         (a)      In the event the purchase and sale contemplated by this
                  Agreement is completed and if, for any reason, the Parties
                  while in agreement to Close this transaction are unable on the
                  Closing Date to cause the Purchaser to become the recognized
                  owner of the Securities, Nexen Seismic, Pipeline and the
                  Office and Administrative Assets or the Partnership to become
                  the recognized holder of any of the Assets in the place and
                  stead of the Vendor or its Affiliates, then subject to Clause
                  19(b) (except in the case of specific conveyances comprising
                  declarations of trust in respect of portions of the Assets),
                  the Vendor shall:

                  (i)      hold and stand possessed of such Securites, Nexen
                           Seismic, Pipeline and Office and Administrative
                           Assets and Assets fully on behalf of the Purchaser or
                           Partnership, as applicable, as bare trustee, and
                           receive and hold all proceeds, benefits, and
                           advantages in respect of the same fully for the
                           benefit, use and ownership of the Partnership or the
                           Purchaser, as applicable, pursuant to and in
                           accordance with Clause 5 and the provisions of Clause
                           5 shall apply MUTATIS MUTANDIS to such bare trust
                           created hereunder;

                  (ii)     in a timely manner, deliver to the Partnership or the
                           Purchaser, as applicable, all revenues, proceeds and
                           other benefits received by the Vendor from the
                           Assets;

                  (iii)    in a timely manner, deliver to the Partnership or the
                           Purchaser, as applicable, all Third Party notices and
                           communications received by it in respect of the
                           Assets, the Pipeline, Nexen Seismic and the Office
                           and Administrative Assets;

                  (iv)     in a timely manner, deliver to Third Parties all such
                           notices and communications as the Partnership may
                           reasonably request and all such monies and other
                           items as the Partnership may reasonably provide in
                           respect of the Assets, the Pipeline, Nexen Seismic
                           and the Office and Administrative Assets; and

                  (v)      as agent of the Purchaser and the Partnership, do and
                           perform all such acts and things and execute and
                           deliver all such agreements, notices and other
                           documents and instruments as the Purchaser and the
                           Partnership may reasonably request in writing for
                           purposes of facilitating the exercise of rights
                           incidental to the ownership of the Assets, the
                           Pipeline, Nexen Seismic and the Office and
                           Administrative Assets; and

                  (vi)     in a timely manner after Closing, complete all joint
                           venture billing, computation and payment of
                           royalties, filing of production reports with
                           appropriate governmental authorities, payment of
                           lease rentals and property taxes and similar
                           administrative activities for all periods prior to
                           the Closing Date.

         (b)      The trust created hereunder shall terminate and Vendor's
                  responsibilities thereto shall cease upon completion of all
                  registrations, transfers or assignments and novations
                  pertaining to such Assets, Securities, Nexen Seismic, Pipeline
                  and/or Office and Administrative Assets, as applicable.

         (c)      The Vendor and its Affiliates shall not be liable to either
                  the Purchaser or the Partnership for any loss or damage
                  suffered by the Purchaser and/or the Partnership in connection
                  with the arrangement established under Clause 19(a), except to
                  the extent that the loss or damage is caused by the Vendor's
                  and its Affiliates gross negligence or its willful misconduct,
                  and the Purchaser and the Partnership, jointly and severally,
                  shall indemnify and save harmless the Vendor and its
                  Affiliates and their directors, officers, servants, agents and
                  employees from and against all Losses and Liabilities which
                  may be brought


                                      -49-


                  against or suffered by any of them arising out of the
                  performance by the Vendor or its Affiliates of their
                  obligations under Clause 19(a). An act or omission of the
                  Vendor, its Affiliates, or their directors, officers,
                  servants, agents or employees shall not be regarded as gross
                  negligence or willful misconduct to the extent it was done or
                  omitted to be done in accordance with the instructions or
                  concurrence of the Purchaser and the Partnership. Nothing in
                  this Clause 19 shall be construed as extending or restricting
                  or limiting in any manner any of the other covenants,
                  warranties, representations or other obligations of the
                  Parties under this Agreement.

         (d)      All costs incurred in connection with the operations of the
                  Assets, Nexen Seismic, Pipeline and Office and Administrative
                  Assets after the Closing Date until the Vendor is relieved of
                  its responsibilities as operator or trustee of the Assets,
                  shall be reimbursed, within five (5) Business Days of
                  Purchaser's receipt of Vendor's request for reimbursement, by
                  the Purchaser and/or the Partnership to the Vendor.

         (e)      After Closing, Vendor may remove any signs that indicate
                  ownership or operation of the Assets. It shall be the
                  responsibility of Purchaser, where necessary, to erect or
                  install any signs that may be required by governmental
                  agencies indicating Purchaser and/or the Partnership to be the
                  operator of the Assets and to notify other working interest
                  parties, gas purchasers, suppliers, contractors, governmental
                  agencies and any other parties of Purchaser's and/or the
                  Partnership's interests in the Assets.

         (f)      As soon as reasonably possible after Closing and in no event
                  later than thirty (30) days, Purchaser shall, at its sole cost
                  and expense:

                  (i)      change the name of the Partnership from "Nexen Canada
                           No. 1" to another name not infringing or conflicting
                           with Vendor's corporate names or trademarks, and
                           Purchaser shall provide Vendor proof, satisfactory to
                           Vendor, of such name change; or, cause the
                           Partnership to be dissolved and wound-up and
                           Purchaser shall provide Vendor proof, satisfactory to
                           Vendor, of same; and

                  (ii)     change the name of Subco from "CNYL No. 1 Ltd." to
                           another name not infringing or conflicting with
                           Vendor's corporate names or trademarks, and Purchaser
                           shall provide Vendor proof, satisfactory to Vendor,
                           of such name change; or, cause the Partnership to be
                           dissolved and wound-up and Purchaser shall provide
                           Vendor proof, satisfactory to Vendor, of same.

         (g)      The Vendor shall use reasonable efforts to assist the
                  Purchaser and/or the Partnership in continuing to act as the
                  operator or assuming the operation and management of the
                  Assets, where and to the extent the Vendor and/or the
                  Partnership is operator of such Assets, however the Purchaser
                  acknowledges and agrees that nothing in this Agreement shall
                  be interpreted as any assurance that the Partnership will
                  continue to operate the Assets or that Purchaser will be able
                  to serve as operator of any of the Assets it receives
                  hereunder.

        [ INTENTIONALLY DELETED ]


                                      -50-


         (i)      The provisions of this Clause 19 shall survive the Closing
                  Date.

20.      CONFIDENTIALITY

         (a)      Subject to Clause 20(c), until Closing has occurred, the
                  Purchaser shall keep confidential all information obtained
                  from the Vendor in connection with the Assets, Office and
                  Administrative Assets, Nexen Seismic, Pipeline and the
                  Securities. Any additional information obtained as a result of
                  access under Clause 6 which does not relate to the Assets
                  shall continue to be treated as confidential and shall not be
                  used by the Purchaser without the prior written consent of the
                  Vendor. The restrictions on disclosure and use of information
                  set forth in this Clause 18(a) shall not apply to information
                  to the extent it:

                  (i)      is or becomes publicly available through no act or
                           omission of the Purchaser or its consultants or
                           advisors;

                  (ii)     is subsequently obtained lawfully from a Third Party
                           which, after reasonable inquiry, the Purchaser does
                           not know to be bound to the Vendor to restrict the
                           use or disclosure of such information;

                  (iii)    is already in the Purchaser's possession at the time
                           of disclosure, without restriction on disclosure;

                  (iv)     is required to be disclosed by the Purchaser under
                           legal compulsion, including those public disclosure
                           requirements as required by securities laws and the
                           rules and regulations of the applicable Stock
                           Exchanges and securities commissions;

                  (v)      is required to be disclosed for the purpose of
                           obtaining consents or complying with Preferential
                           Rights; or

                  (vi)     is required to be disclosed to obtain the consent of
                           a lender, or which a Party may choose to disclose to
                           recognized credit rating agencies in respect of its
                           credit rating.

         (b)      If the Purchaser employs consultants, agents or advisors to
                  assist in its review of the Assets pursuant to Clause 6, the
                  Purchaser shall be responsible to the Vendor for ensuring that
                  such consultants, agents and advisors comply with the
                  restrictions on the use and disclosure of information set
                  forth in Clause 20(a).

         (c)      The Vendor and the Purchaser shall cooperate with each other
                  in releasing information concerning this Agreement and the
                  transactions provided for by it, and shall furnish to, and
                  discuss with, the other Party drafts of all press and other
                  releases, and shall seek the consent of the other Party (which
                  shall not be unreasonably withheld) prior to the publication
                  thereof.

         (d)      Notwithstanding Clause 20(a), the obligations of the Purchaser
                  under this Clause 20 are in addition to, and not in
                  substitution for, its obligations under any confidentiality
                  agreement made between the Vendor and the Purchaser for its
                  possible acquisition of the Partnership and/or Assets, except
                  as otherwise provided in this Agreement.

         (e)      Neither Party hereto shall make any public or private
                  announcement or communications in respect of the proposed
                  transactions set forth in this Agreement (including, without
                  limitation, the existence of this Agreement or that any
                  investigation, discussions or negotiations are taking place
                  concerning the evaluation of either of the Parties hereto or
                  the proposed transaction) unless the prior approval of the
                  announcement is obtained from


                                      -51-


                  the other Party hereto. Notwithstanding the foregoing, each
                  Party understands that the other Party is subject to public
                  disclosure requirements as required by securities laws and the
                  rules and regulations of the applicable Stock Exchanges and
                  securities commissions. In the event that either Party
                  determines that it is required by such laws, rules and
                  regulations to make any public disclosure, then the Party
                  shall give prior notice to the other Party and an opportunity
                  will be provided for discussion.

21.      ATTORNMENT AND PROPER LAW

         (a)      This Agreement shall be exclusively subject to and be
                  interpreted, construed and enforced in accordance with the
                  laws in effect in the Province of Alberta. Each Party
                  irrevocably attorns to the exclusive jurisdiction of the
                  courts of the Province of Alberta and all courts of appeal
                  therefrom.

         (b)      Pursuant to Section 7 of the Limitations Act (Alberta), the
                  Parties expressly provide that the limitation period for all
                  claims as may arise under this Agreement as between the
                  Parties shall be six (6) years from the day the act giving
                  rise to the claim was discovered by the Party making the
                  claim, but in any event shall not be more than fifteen (15)
                  years from the day the act giving rise to the claim occurred.

22.      MISCELLANEOUS

         (a)      At the date hereof and thereafter as may be necessary and
                  without further consideration, the Parties hereto shall
                  execute, acknowledge and deliver such other documents,
                  novations, transfers, instruments and agreements and shall do
                  such other things as may be necessary to carry out their
                  respective obligations under this Agreement.

         (b)      Time shall be of the essence in this Agreement.

         (c)      The address for Notices of each of the Parties hereto shall be
                  as follows:

                  Vendor:           c/o Nexen Inc.
                                    801 - 7th Avenue S.W.
                                    Calgary, Alberta  T2P 3P7
                                    Fax:  (403) 699-5800

                  Purchaser:        c/o Harvest Operations Corp.
                                    2100, 330 - 5th Avenue S.W.
                                    Calgary, Alberta   T2P 0L4
                                    Fax:  (403) 265-3490

                  All notices, communications and statements (collectively,
                  "NOTICES") required, permitted or contemplated hereunder shall
                  be in writing, and shall be deemed to be sufficiently given
                  and received if:

                  (i)      personally served on the other Party by delivery
                           during the normal business hours of the recipient at
                           the addresses set forth above (personally served
                           Notices shall be deemed received by the addressee
                           when actually delivered);

                  (ii)     by facsimile or other electronic medium (or by any
                           other like method by which a written or recorded
                           message may be sent) directed to the Party on whom
                           they are to be served at that Party's fax number set
                           forth above, and such Notices so served shall be
                           deemed to have been received by the addressee thereof
                           when


                                      -52-


                           actually received by it if received within the normal
                           working hours of the recipient on a Business Day, or
                           at the commencement of the next ensuing Business Day
                           following transmission thereof; or

                  (iii)    mailed by first class registered post, postage
                           prepaid, to the other Party (Notices so served shall
                           be deemed to have been received by the addressee on
                           the fourth Business Day following the date of mailing
                           thereof); except in the event of an actual or
                           threatened postal strike or other labour disruption
                           that may affect the mail service.

                  Either of the Parties hereto may from time to time change its
                  address for service herein by giving Notice to the other
                  Party.

         (d)      This Agreement constitutes the entire agreement between the
                  Parties and supersedes and replaces all previous oral or
                  written agreements, memoranda, correspondence by the parties
                  hereto prior to the date entered into and undertakings and
                  representations made (save other than for these made
                  fraudulently) hereof.

         (e)      This Agreement shall be binding upon and shall inure to the
                  benefit of the Parties hereto and their respective trustees,
                  receivers, receiver-managers, successors and permitted
                  assigns.

         (f)      This Agreement may be executed in as many counterparts as are
                  necessary and all executed counterparts together shall
                  constitute one agreement.

         (g)      Notwithstanding anything contained herein, with respect to the
                  files, records and other documents included in the
                  Miscellaneous Interests, for a period of seven (7) years after
                  the Closing Date, Purchaser shall give Vendor reasonable
                  access to such files, records and other documents included in
                  the Miscellaneous Interests acquired from Vendor and will make
                  its personnel reasonably available for the purpose of
                  providing Vendor, upon Vendor's reasonable request, with
                  assistance in locating information from such records,
                  providing appropriate verifications of documents and
                  information, developing information, reports, submissions and
                  the like relating to Vendor's operation of the Assets prior to
                  the Closing Date, or otherwise providing reasonable assistance
                  which the Parties mutually deem appropriate.

        [ INTENTIONALLY DELETED ]


                                      -53-


                 [ INTENTIONALLY DELETED ]

         (i)      Neither Party may assign its interest hereunder without the
                  prior written consent of the other Party except that the
                  Purchaser may assign this Agreement to an Affiliate or
                  Affiliates with Vendor's written consent, not to be
                  unreasonably withheld.




                                      -54-


         IN WITNESS WHEREOF the parties hereto have executed this Agreement as
of the date first above written.


NEXEN INC.                                  HARVEST BREEZE TRUST NO. 1, BY ITS
                                            TRUSTEE  1115638 ALBERTA LTD.

                                            Per: _______________________________
Per: _______________________________
                                            Per: _______________________________

CANADIAN NEXEN YEMEN LTD.                   HARVEST BREEZE TRUST NO. 2, BY ITS
                                            TRUSTEE  1115650 ALBERTA LTD.

Per: _______________________________        Per: _______________________________

Per: _______________________________        Per: _______________________________

NEXEN MARKETING

Per: _______________________________

Per: _______________________________





                                  SCHEDULE "A"
[Intentionally Deleted]








                                  SCHEDULE "B"

         [Intentionally Deleted]






                                  SCHEDULE "C"

[Intentionally Deleted]






                                  SCHEDULE "D"

[Intentionally Deleted]






                                  SCHEDULE "E"

         TO A PARTNERSHIP PURCHASE AGREEMENT THE 23RD DAY OF JUNE, 2005
                                     BETWEEN
            NEXEN INC., CANADIAN NEXEN YEMEN LTD. AND NEXEN MARKETING
                                       AND
            HARVEST BREEZE TRUST NO.1 AND HARVEST BREEZE TRUST NO. 2.



                               MARKETING CONTRACTS
                               -------------------

                                 ATTACHED HERETO






                                  SCHEDULE "F"

[Intentionally Deleted]






                                  SCHEDULE "G"
[Intentionally Deleted]






                                  SCHEDULE "H"

[Intentionally Deleted]






                                  SCHEDULE "I"

[Intentionally Deleted]






                                  SCHEDULE "J"

[Intentionally Deleted]