PURCHASE AND SALE AGREEMENT

                                   between

                          ENSERCH EXPLORATION, INC.,

                                  as Seller,

                                     and

                        ABRAXAS PETROLEUM CORPORATION,

                                  as Buyer.





                                 May 22, 1996








                              TABLE OF CONTENTS



1.    Property to be Sold and Purchased................................1

2.    Purchase Price...................................................2

3.    Deposit..........................................................2

4.    Seller's Representations.........................................3

5.    Buyer's Representations..........................................4

6.    Certain Covenants of Seller and Buyer Pending Closing............5

7.    Due Diligence Reviews............................................8

8.    Certain Price Adjustments.......................................11

9.    Conditions Precedent to Buyer's Obligations.....................12

10.   Conditions Precedent to Seller's Obligations....................13

11.   The Closing.....................................................13

12.   Certain Accounting Adjustments..................................16

13.   Assumption and Indemnification..................................18

14.   Disclaimer of Warranties........................................19

15.   Commissions.....................................................20

16.   Casually Loss...................................................20

17.   Notices.........................................................21

18.   Survival of Provisions..........................................22

19.   Miscellaneous Matters...........................................22

EXHIBIT A............................................................A-1
EXHIBIT B............................................................B-1
EXHIBIT C............................................................C-1
EXHIBIT D............................................................D-1
EXHIBIT E............................................................E-1










                         PURCHASE AND SALE AGREEMENT


      This  Agreement,  dated  May 22,  1996,  is made  by and  between  ENSERCH
EXPLORATION,   INC.,   (hereinafter   called  "Seller")  and  ABRAXAS  PETROLEUM
CORPORATION (hereinafter called "Buyer");



                                 WITNESSETH:


      1. Property to be Sold and  Purchased.  Seller  agrees to sell,  and Buyer
agrees to purchase,  for the consideration  hereinafter set forth, pursuant to a
special warranty of title by, through and under Seller as limited in Section 14,
but not otherwise, and subject to the terms and provisions herein contained, the
following described properties, rights, and interests:

            (a) All rights,  titles and  interests  of Seller in and to the oil,
      gas  and  mineral   leases   described   in  Exhibit  A  hereto  (and  any
      ratifications  and  amendments  to  such  leases,   whether  or  not  such
      ratifications  and  amendments  are  described  in  Exhibit  A) and all of
      Seller's right,  title,  and interest in and to the fee mineral  interests
      described in Exhibit A, if any; and

            (b) All  rights,  titles,  and  interests  of  Seller  in and to, or
      otherwise  derived  from,  all  presently  existing and valid oil, gas and
      mineral   unitization,    pooling,    and   communitization    agreements,
      declarations,  and orders (including, without limitation, all units formed
      under orders, rules,  regulations,  or other official acts of any federal,
      state, or other authority having jurisdiction,  and voluntary  unitization
      agreements,  designations  and  declarations)  relating to the  properties
      described  in  subsection  1(a) to the extent  such  rights,  titles,  and
      interests are attributable to the properties described in subsection 1(a);
      and

            (c) All  rights,  titles,  and  interests  of  Seller  in and to all
      presently  existing  and  valid  production  sales  contracts,   operating
      agreements,  and other  agreements and contracts that relate to any of the
      properties  described  in  subsections  1(a) and 1(b),  to the extent such
      rights, titles, and interests are attributable to the properties described
      in subsections 1(a) and 1(b); and

            (d) All crude oil,  natural  gas,  casinghead  gas,  drip  gasoline,
      natural gasoline,  petroleum, natural gas liquids,  condensate,  products,
      liquids and other  hydrocarbons  and other  minerals or materials of every
      kind and  description,  including  without  limitation,  "line  fill"  and
      inventory  below  the  pipeline  connection  in  tanks,  insofar  as  such
      hydrocarbons  may be produced from or are  attributable  to the properties
      described  in  Sections  1(a)  and  1(b)  after  the  Effective  Date,  as
      hereinafter defined.

            (e) All  rights,  titles,  and  interests  of  Seller  in and to all
      materials,  supplies,  machinery,   equipment,   improvements,  and  other
      personal property and fixtures (including,  but not limited to, all wells,
      wellhead, equipment, pumping units, flowlines, tanks, buildings, injection
      facilities,   saltwater  disposal  facilities,   compression   facilities,
      gathering  systems,   and  other  equipment)  located  on  the  properties
      described in  subsections  1(a) and 1(b) and used in  connection  with the
      exploration, development, operation, or maintenance thereof.

The properties and interests specified in subsections 1(a), 1(b), 1(c), 1(d) and
1(e) are herein sometimes collectively called the "Properties." The defined term
"Properties" shall not include seismic data,  geological or geophysical data, or
other  similar  data,  or any  interpretations  thereof or other data or records
related  thereto except that Seller shall provide Buyer with copies of such data
and records in its  possession and a license to seismic data, if permitted to do
so by third  party  contracts.  Such data and  records  shall not be  subject to
Defects as defined in Section 7 herein.

      2. Purchase Price. The unadjusted  purchase price for the Properties shall
be FORTY SEVEN MILLION,  FIVE HUNDRED  THOUSAND  Dollars  ($47,500,000)  (herein
called the "Base Purchase Price").  The Base Purchase Price may be adjusted,  as
provided in Sections 6(c) and 8 hereof.  The Base Purchase Price, as so adjusted
and as otherwise  adjusted by mutual  agreement of the parties herein,  shall be
called the "Purchase  Price." Buyer shall pay the Purchase  Price in cash at the
Closing,  as  hereinafter  provided.  The  Purchase  Price shall be increased to
include  interest  at the  rate of  seven  percent  (7%)  per  annum on the Base
Purchase  Price  compounded  on the  first  day of each  month  for  the  period
commencing on the Effective Date and ending on the Closing Date.

      3. Deposit.  Contemporaneous  with its execution of this Agreement,  Buyer
paid to Seller  THREE  MILLION,  EIGHT  HUNDRED  THOUSAND  Dollars  ($3,800,000)
(hereinafter  called  the  "Deposit").   If  Buyer  and  Seller  consummate  the
transaction contemplated hereby in accordance with the terms hereof, the Deposit
shall be applied to the Purchase  Price.  If Buyer and Seller do not  consummate
the transaction  contemplated  hereby because of a material default by Seller in
the absence of a material  default by Buyer,  Seller shall return the Deposit to
Buyer. If Buyer and Seller terminate this Agreement under Section 9 or 10 hereof
in a circumstance  where such Section  provides for return of the Deposit,  then
Seller  shall return the Deposit to Buyer.  Except as provided in the  preceding
two  sentences,  if  Buyer  fails  or  refuses  to  consummate  the  transaction
contemplated  hereby, or if the transaction  contemplated hereby otherwise fails
to close on the Closing  Date,  Seller  shall  retain the Deposit as  liquidated
damages.  The  parties  agree  that  damages in such  event  would be  extremely
difficult  to  determine,  that the  Deposit  represents  a fair and  reasonable
estimate of such damages under the  circumstances,  and that such a retention of
the Deposit does not constitute a penalty.






      4.    Seller's Representations.  Seller represents to Buyer that:

            (a) Seller is a  corporation  duly  organized  and legally  existing
      under the laws of its state of  incorporation.  Seller is  qualified to do
      business and is in good  standing,  or will be at Closing,  in each of the
      states in which  Properties  are  located,  where  the laws of such  state
      require a  corporation  owning  the  Properties  located  in such state to
      qualify to do business.

            (b) Seller has full power to enter this  Agreement  and  perform its
      obligations  hereunder  and has taken  all  proper  action  to enter  this
      Agreement and perform its obligations hereunder.

            (c)  Seller's   execution  and  delivery  of  this  Agreement,   the
      consummation  of  the  transaction   contemplated   hereby,  and  Seller's
      compliance with the terms hereof, will not result in any default under any
      agreement  or  instrument  to which  Seller  is a party  or by  which  the
      Properties are bound that would be material to this transaction.  Seller's
      execution and delivery of this Agreement will not violate any order, writ,
      injunction,  decree,  statute, rule, or regulation applicable to Seller or
      to the Properties that would be material to this  transaction,  except the
      following:

            (i)   Any  consents  to  assignment  or  waivers  of  preferential
                  rights to purchase that must be obtained from third parties;

            (ii)  Compliance    with    the    Hart-Scott-Rodino     Antitrust
                  Improvements Act of 1976, as amended (the "HSR Act");

            (iii) Any approvals that must be obtained from governmental entities
                  that are lessors under leases  included in the  Properties (or
                  who  administer  such  leases for such  lessors)  and that are
                  customarily obtained post-closing; and

            (iv)  Any maintenance of uniform  interest  provisions  contained in
                  any operating or other agreements.

            (d) This Agreement  constitutes (and the Assignment and Bill of Sale
      provided  for in  Section  1.1(a)(i)  hereof  and any other  documentation
      provided  for herein to be executed by Seller,  will,  when  executed  and
      delivered,  constitute)  the legal,  valid,  and  binding  obligations  of
      Seller,  enforceable  according  to their  terms,  except  as  limited  by
      bankruptcy or other laws applicable  generally to creditor's rights and as
      limited by general equitable principles.

            (e) Except as  disclosed  on Exhibit D, there are no pending  suits,
      actions,  or other proceedings,  not filed by Seller, in which Seller is a
      party  that   materially   affect  the  Properties   (including,   without
      limitation, any actions challenging or pertaining to Seller's title to any
      of the  Properties)  or  affecting  the  execution  and  delivery  of this
      Agreement or the consummation of the transaction contemplated hereby.

            (f) To the  knowledge  of Seller as of the date of execution of this
      Agreement,  all material ad valorem,  production,  severance,  excise, and
      similar taxes and  assessments  based upon or measured by the ownership of
      or the production of  hydrocarbons  from the Properties  which have become
      due and payable have been  properly  paid or are being  challenged in good
      faith by Seller, all applicable tax returns relating to the same have been
      filed,  and Seller knows of no claim by any  applicable  taxing  authority
      against Seller in connection with the payment of such taxes.

      5.    Buyer's Representations.  Buyer represents to Seller that:

            (a) Buyer is a corporation duly organized and legally existing under
      the laws of its state of  organization.  Buyer is qualified to do business
      and is in good standing,  or will be at Closing,  in each of the states in
      which  Properties  are  located  where  the laws of such  state  require a
      corporation  owning the Properties  located in such state to qualify to do
      business.

            (b) Buyer has full power to enter into and perform  its  obligations
      under  this  Agreement  and has taken  all  proper  action  to enter  this
      Agreement and perform its obligations hereunder.

            (c)  Buyer's   execution  and  delivery  of  this   Agreement,   the
      consummation  of  the  transaction   contemplated   hereby,   and  Buyer's
      compliance with the terms hereof, will not result in any default under any
      Agreement  or  instrument  to  which  Buyer  is a party  or by  which  the
      Properties are bound that would be material to this  transaction.  Buyer's
      execution and delivery of this Agreement will not violate any order, writ,
      injunction,  decree, statute, rule or regulation applicable to Buyer or to
      the  Properties  that would be  material to this  transaction,  except the
      following:

            (i)   Any  consents  to  assignment  or  waivers  of  preferential
                  rights to purchase that must be obtained from third parties;

            (ii)  Compliance with the "HSR Act";

            (iii) Any approvals that must be obtained from governmental entities
                  that are lessors under leases  included in the  Properties (or
                  who  administer  such  leases for such  lessors)  and that are
                  customarily obtained post-closing; and

            (iv)  Any maintenance of uniform  interest  provisions  contained in
                  any operating or other agreements.

            (d) This Agreement constitutes,  and the Assignment and Bill of Sale
      provided  for in  Section  1.1(a)(i)  hereof  and any other  documentation
      provided  for herein to be  executed by Buyer,  will,  when  executed  and
      delivered, constitute, the legal, valid, and binding obligations of Buyer,
      enforceable  according to their terms,  except as limited by bankruptcy or
      other laws  applicable  generally to  creditor's  rights and as limited by
      general equitable principles.

            (e) There are no pending suits,  actions, or other proceedings,  not
      filed by Buyer,  in which  Buyer is a party  that  materially  affect  the
      execution  and  delivery  of this  Agreement  or the  consummation  of the
      transaction contemplated hereby.

            (f) Buyer is a knowledgeable  purchaser,  owner, and operator of oil
      and gas properties, has the ability to evaluate (and has evaluated or will
      evaluate prior to Closing) the  Properties for purchase,  and is acquiring
      the  Properties  for its own  account  and not with the  intent  to make a
      distribution  within the meaning of the Securities Act of 1933, as amended
      (and the rules and  regulations  pertaining  thereto),  or a  distribution
      thereof in violation of any other applicable  securities  laws,  rules, or
      regulations.

            (g) With  regard to those  Properties  which Buyer seeks to operate,
      Buyer is, or will become,  qualified to operate such Properties  under the
      applicable  laws,  rules and regulations of the jurisdiction in which such
      Properties are located.

      6.    Certain  Covenants of Seller and Buyer  Pending  Closing.  Between
the date of this Agreement and the Closing Date:

            (a)   Seller shall permit Buyer access as follows:

            (i)   Seller  shall  give  Buyer  and  its   attorneys  and  other
                  representatives,  who have a legitimate need to know, access
                  at all reasonable  times during normal business hours to the
                  Properties  and, at  Seller's  office,  to Seller's  records
                  (including,  without limitation, title files, division order
                  files,   well   files,    production   records,    equipment
                  inventories,  and production,  severance, and ad valorem tax
                  records)  pertaining  to the  ownership and operation of the
                  Properties,    to   conduct   due   diligence   reviews   as
                  contemplated  by Section 7 below.  Buyer may make  copies of
                  such  records,  at its  expense,  but  shall,  if  Seller so
                  requests,  return all copies so made if the Closing does not
                  occur.  Seller shall not be obligated to provide  Buyer with
                  access to any  records or data that Seller  considers  to be
                  proprietary  or  confidential  or that Seller cannot provide
                  to Buyer without,  in its opinion,  breaching,  or risking a
                  breach of,  confidentiality  agreements  with other parties.
                  Any  records  or  data  provided  shall  be  subject  to the
                  Confidentiality  Agreement.  Seller makes no  representation
                  or warranty of any kind as to the  accuracy or  completeness
                  of any materials made available to Buyer in connection  with
                  the transaction contemplated hereby.

            (ii)  Seller  shall make a good  faith  effort to give  Buyer,  or
                  Buyer's  authorized  representatives,  who have a legitimate
                  need to know, at reasonable  times and upon adequate  notice
                  to  Seller,  physical  access  to  the  Properties  for  the
                  purpose of inspecting  same.  Buyer  recognizes that some or
                  all of the  Properties may be operated by parties other than
                  Seller and that  Seller's  ability to obtain  access to such
                  properties,  and the manner and  extent of such  access,  is
                  subject to the consent of such third  parties.  Buyer agrees
                  to  comply   fully   with  the   rules,   regulations,   and
                  instructions  issued by Seller (and,  where  Properties  are
                  operated by other  parties,  such third  parties)  regarding
                  the actions of Buyer while  upon,  entering,  or leaving the
                  Properties.

            (iii) Exculpation and Indemnification.  If Buyer exercises rights of
                  access   under  this   Section  or   otherwise,   or  conducts
                  examinations  or inspections  under this Section or otherwise,
                  then (a) such access, examination,  and inspection shall be at
                  Buyer's sole risk,  cost,  and  expense,  and Buyer waives and
                  releases all claims against  Seller (its  affiliates and their
                  respective   directors,   officers,   employees,    attorneys,
                  contractors,  and agents)  arising in any way  therefrom or in
                  any way connected  therewith or arising in connection with the
                  conduct  of its  directors,  officers,  employees,  attorneys,
                  contractors, and agents in connection therewith; and (b) BUYER
                  SHALL RELEASE,  INDEMNIFY,  DEFEND,  AND HOLD HARMLESS  SELLER
                  (AND ITS PARENT, SUBSIDIARY COMPANIES AND OTHER AFFILIATES AND
                  THEIR RESPECTIVE OFFICERS,  DIRECTORS,  EMPLOYEES,  ATTORNEYS,
                  CONTRACTORS, AND AGENTS) (HEREINAFTER COLLECTIVELY REFERRED TO
                  AS "SELLER GROUP") FROM ANY AND ALL CLAIMS, ACTIONS, CAUSES OF
                  ACTION,  LIABILITIES,  DAMAGES,  LOSSES,  COSTS,  OR  EXPENSES
                  (INCLUDING,  WITHOUT  LIMITATION,  COURT COSTS AND  REASONABLE
                  ATTORNEY'S  FEES),  OR  LIENS  OR  ENCUMBRANCES  FOR  LABOR OR
                  MATERIALS,  ARISING OUT OF OR IN ANY WAY  CONNECTED  WITH SUCH
                  MATTERS. THE FOREGOING RELEASE AND INDEMNIFICATION SHALL APPLY
                  WHETHER  OR  NOT  SUCH  CLAIMS,  ACTIONS,  CAUSES  OF  ACTION,
                  LIABILITIES,  DAMAGES,  LOSSES, COSTS OR EXPENSES ARISE OUT OF
                  (i) NEGLIGENCE (INCLUDING SOLE NEGLIGENCE,  SINGLE NEGLIGENCE,
                  CONCURRENT  NEGLIGENCE,  ACTIVE  OR  PASSIVE  NEGLIGENCE,  BUT
                  EXPRESSLY   NOT   INCLUDING   GROSS   NEGLIGENCE   OR  WILLFUL
                  MISCONDUCT) OF SELLER OR ANY OTHER INDEMNIFIED  PARTY, OR (ii)
                  STRICT LIABILITY.

            (b) Seller shall  continue to operate in the ordinary  course of its
      business any portion of the  Properties  over which it serves as operator.
      Except for the transaction  contemplated  by this Agreement,  Seller shall
      not sell or otherwise  dispose of any material  portion of the Properties.
      Seller shall not,  without the prior written  consent of Buyer,  (i) enter
      into new gas sales  contracts  or new crude oil sales or supply  contracts
      with respect to the Properties except Seller may enter into such contracts
      that are terminable at will (without penalty or detriment) on notice of 30
      days or less;  or (ii)  incur or agree to incur any  material  contractual
      obligation  with respect to the  Properties  except as may be necessary to
      protect  health  and  safety or the  environment.  If Seller  receives  or
      desires to make any proposal to drill an additional well on the Properties
      or to conduct other  operations that require the consent of  non-operators
      under any applicable  operating  agreement,  it shall notify Buyer thereof
      and shall consult with Buyer  concerning  such proposal.  However,  Seller
      shall make its decision  regarding such proposal in its own discretion and
      in the ordinary course of its business.

            (c) Seller shall use reasonable  efforts,  consistent  with industry
      practices in transactions of this type, to identify,  with respect to each
      material  portion  of the  Properties,  (i)  all  preferential  rights  to
      purchase  and all  rights  of third  parties  to  withhold  consent  to an
      assignment  that would apply to the  transaction  contemplated  hereby and
      (ii) the parties holding such rights.  In attempting to identify the same,
      Seller shall not be  obligated to go beyond its own records.  Seller shall
      request  from  the  parties  so  identified  (and in  accordance  with the
      documents  creating  such rights)  waivers of the  preferential  rights to
      purchase and consents to  assignment so  identified.  Seller shall have no
      obligation  hereunder other than to attempt to identify such  preferential
      rights and rights to withhold  consent to  assignment  and to request such
      waivers and  consents.  Seller  shall not be obligated to assure that such
      waivers and consents are obtained. Seller may tender to any party refusing
      to waive such a preferential right the interest covered by such right at a
      price equal to the amount specified in Exhibit B for such interest. To the
      extent that such an interest is actually sold to a party exercising such a
      preferential right, it shall be excluded from the transaction contemplated
      hereby,  and the Base  Purchase  Price shall be reduced by the amount such
      party paid to Seller for such  interest  unless the parties  hereto  agree
      otherwise.

            (d) If  applicable,  as  soon as  practicable  after  the  execution
      hereof, Buyer and Seller shall prepare and submit any necessary filings in
      connection with the  transaction  contemplated by this Agreement under the
      HSR Act.  Buyer shall pay all filing fees in connection  with such filing.
      Buyer and Seller shall request early  termination of the waiting period by
      the FTC,  shall promptly make any  appropriate or necessary  subsequent or
      supplemental  filings,  and  shall  furnish  to each  other  copies of all
      filings  made  under the HSR Act on the same day that they are filed  with
      the FTC. Seller shall  cooperate with Buyer as to all filings  required by
      the HSR Act.

      7.    Due Diligence Reviews.

            (a)   The term  "Defect"  as used in this  Section  shall mean the
      following:

            (i)   Seller's  ownership  of a well or unit  listed on  Exhibit B
                  hereto  (A)  entities  Seller to receive a share of the oil,
                  gas, and other hydrocarbons  produced from, or allocated to,
                  such  well or unit  that is less than the share set forth on
                  Exhibit  B in  connection  with  such  well  or  unit in the
                  column  headed "Net Revenue  Interest" or (B) causes  Seller
                  to bear a share of the cost of  operating  such well or unit
                  greater  than the share set forth on Exhibit B for such well
                  or unit in the column headed "Operating  Interest"  (without
                  a  proportionate  increase  in the  share of  production  to
                  which Seller is entitled from such well or unit); or

            (ii)  Seller's  ownership  of a Property  is subject to a lien other
                  than (A) a lien that will be  released  at or before  Closing,
                  (B) a lien for taxes not yet  delinquent,  (C) a mechanic's or
                  materialmen's  lien (or  other  similar  lien),  or (D) a lien
                  under an  operating  agreement  or similar  agreement,  to the
                  extent the same relates to expenses  incurred that are not yet
                  due; or

            (iii) Seller's sale of a Property is subject to a preferential right
                  to purchase  or may not be  assigned  without the consent of a
                  third party, unless a waiver of such right or such consent has
                  been  obtained  with respect to the  transaction  contemplated
                  hereby or an appropriate tender of the applicable interest has
                  been made to the party  holding  such  right and the period of
                  time  required  for such  party to  exercise  such  right  has
                  expired without such party exercising such right; or

            (iv)  Seller's ownership of a Property is subject to an imperfection
                  in title that, if asserted,  would cause a Defect,  as defined
                  in clause (i) above, to exist, and such  imperfection in title
                  normally would not be waived by persons engaged in the oil and
                  gas business purchasing producing property; or

            (v)   Seller's rights and interests in the Properties are subject to
                  reduction  by a third party  reversionary,  back-in or similar
                  right, except as shown on Exhibit A or Exhibit B; or

            (vi)  Seller is in default  under a material  provision  of a lease,
                  farmout  agreement,  or other contract or agreement  affecting
                  the Properties such that Seller is not entitled to receive the
                  production of hydrocarbons attributable to the interests shown
                  on Exhibit B; or

            (vii) A Property has been cited for, or in its present  condition is
                  in, violation of Applicable Environmental Laws (as hereinafter
                  defined) in any material  respect  unless such  violation  has
                  been  cured  (by   remediation,   agreement  with  appropriate
                  authorities,   or  otherwise,   or  by  determination  that  a
                  violation  does not  exist)  or is  disclosed  on  Exhibit  D.
                  "Applicable Environmental Laws" shall mean all federal, state,
                  or local laws,  rules,  orders, or regulations in effect as of
                  the Effective Date of this  Agreement  pertaining to health or
                  the  environment,  including those relating to waste materials
                  and hazardous substances.

            (viii)Prior to the  Effective  Date,  a well located on the Property
                  has been plugged and abandoned and the surface  restored other
                  than in accordance with  applicable  regulatory laws in effect
                  at the time of the  plugging  operation  and such failure will
                  cause the owner of the affected  Property to incur  additional
                  plugging and  abandonment  or surface  restoration  expense to
                  bring such Property into  compliance  with  regulatory laws in
                  effect at the time of the original  plugging  operations.  The
                  amount of the Defect shall be the minimum additional  plugging
                  and abandonment or surface  restoration  expense  necessary to
                  meet the regulatory  requirements in effect at the time of the
                  original plugging  operations.  This Defect shall not apply to
                  wells  located on the Property  that have not been the subject
                  of plugging and  abandonment  operations.  In lieu of reducing
                  the Purchase  Price for the amount of such Defect,  the Seller
                  may elect to conduct and pay for the  additional  plugging and
                  abandonment or surface restoration operations.

            (b)   A gas imbalance does not  constitute a Defect,  and shall be
      handled under the provisions of Section 12. hereof.

            (c) Buyer may  conduct,  to the extent it deems  appropriate  at its
      sole cost,  such  examinations  and  investigations  as it may choose with
      respect to the Properties in order to determine  whether  "Defects" exist.
      If Defects come to Buyer's  attention,  and if Buyer is unwilling to waive
      one or more of such Defects,  Buyer shall notify Seller in writing of such
      Defects  as soon as they are  identified,  but no later than five (5) days
      prior to the date upon which  Closing is  scheduled  to occur  pursuant to
      Section 11 [and not as extended pursuant to 11(i) or 11(ii)]  (hereinafter
      "Defect Notice Date").  Those Defects  identified in such notice to Seller
      are herein called "Asserted Defects." Such notification shall include, (i)
      a description  of the Asserted  Defect,  the lease or mineral  interest on
      Exhibit A affected by such Asserted Defect,  the wells and units listed on
      Exhibit  B to  which  the  Asserted  Defect  relates,  and all  supporting
      documentation  reasonably  necessary  fully to describe  the basis for the
      Asserted  Defect;  (ii) for each  applicable well or unit, the size of any
      variance from "Net Revenue Interest" or "Operating  Interest" set forth in
      Exhibit B that does or could result from such Asserted  Defect;  and (iii)
      the amount by which Buyer proposes to adjust the Purchase Price because of
      such  Asserted  Defect.  Buyer hereby  waives all Defects that it fails to
      identify  to Seller as  Asserted  Defects on or before  the Defect  Notice
      Date. If Buyer notifies Seller of Asserted Defects,  Seller (i) shall have
      the right  (but not the  obligation)  to  attempt  to cure  such  Asserted
      Defects prior to Closing, and (ii) shall also have the right (which may be
      exercised at any time before the Closing  Date) to postpone the Closing by
      designating  a new Closing  Date not later than thirty (30) days after the
      Closing Date then existing,  if Seller desires  additional time to attempt
      to cure  (including  determining  if it will  attempt to cure) one or more
      Asserted  Defects.  In lieu of curing or  attempting  to cure an  Asserted
      Defect, Seller may elect, at any time prior to Closing with respect to any
      Asserted Defect, to indemnify and hold Buyer harmless from and against any
      actual damages or loss  (including  reasonable  attorney's  fees and court
      costs,  but  specifically  excluding  consequential,  special,  or similar
      damages) Buyer may suffer as a result of a third party claim based on such
      Asserted  Defect,  If and when  Seller  makes  such an  election  as to an
      Asserted Defect, such Asserted Defect will be treated under this Agreement
      as cured.

            (d) Buyer shall have the right to make an  environmental  assessment
      of the Properties  during the period beginning on the date of execution of
      this Agreement and ending on the Defect Notice Date.  Buyer and its agents
      shall have the right to enter upon the  Properties  and all  buildings and
      improvements  thereon,  inspect the same, conduct soil and water tests and
      borings, and generally conduct such tests,  examinations,  investigations,
      and studies as may be  necessary or  appropriate  for the  preparation  of
      appropriate  engineering  and other reports in relation to the Properties,
      their  condition,  and the presence of Hazardous  Substances  (as the term
      "Hazardous  Substance"  is  defined  in  the  Comprehensive  Environmental
      Response,  Compensation and Liability Act, 42 U.S.C. Sec. 9601, et seq. ).
      Buyer  agrees  promptly  to provide to Seller a copy of the  environmental
      assessment, including any reports, data, and conclusions. Buyer shall keep
      any data or information  acquired by all such examinations and the results
      of all analyses of such data and  information  strictly  confidential  and
      shall not disclose same to any person or agency  without the prior written
      approval of Seller  unless such  disclosure is required by court order or,
      in the written  opinion of third party legal counsel  acceptable to Seller
      (Seller  acknowledges  Cox & Smith  Incorporated,  San Antonio,  Texas, as
      acceptable),  required to be disclosed pursuant to any statute or any rule
      or regulation of any  environmental  authority  having  jurisdiction  over
      Buyer,  Seller or the Properties;  and, in such event, Seller shall have a
      reasonable  period of time within which it may first  disclose the data or
      information  to the applicable  court or  environmental  authority.  BUYER
      SHALL RELEASE, INDEMNIFY,  DEFEND, AND HOLD HARMLESS THE SELLER GROUP FROM
      AND  AGAINST  ANY  AND ALL  LOSS,  COST,  DAMAGE,  EXPENSE,  OR  LIABILITY
      WHATSOEVER,  INCLUDING  REASONABLE  ATTORNEY'S  FEES,  ARISING  OUT OF ANY
      INJURY TO OR DEATH OF PERSONS OR DAMAGE TO PROPERTY  OCCURRING  IN, ON, OR
      ABOUT THE  PROPERTIES  AS A RESULT  OF SUCH  ACTIVITIES  (EXCEPT  ANY SUCH
      INJURIES  OR  DAMAGES  CAUSED  SOLELY BY THE GROSS  NEGLIGENCE  OR WILLFUL
      MISCONDUCT  OF ANY MEMBER OF THE SELLER  GROUP).  After the Defect  Notice
      Date, Buyer shall be deemed to have inspected the Properties or waived its
      right to inspect the Properties  for all purposes and satisfied  itself as
      to  their  physical  and   environmental   condition,   both  surface  and
      subsurface,  including, but not limited to conditions specifically related
      to the presence, release, or disposal of Hazardous Substances.

      8.    Certain Price Adjustments.

            (a) If Buyer  presents  Asserted  Defects to Seller as a part of the
      due diligence  reviews  provided for in Section 7 above,  and if Seller is
      unable or unwilling to cure such Asserted Defects prior to Closing,  or if
      Buyer has elected to treat a Property affected by a casualty loss pursuant
      to Section 16 as if it were a Property  affected  by an  Asserted  Defect,
      then:

            (i)   Buyer and Seller shall, with respect to each Property affected
                  by  such  matters,   attempt  to  agree  upon  an  appropriate
                  adjustment  to the  valuation  placed  upon such  Property  in
                  Exhibit B to account for such matters; and

            (ii)  With  respect to each  Property as to which Buyer and Seller
                  are  unable  to  agree  upon  appropriate   adjustment  with
                  respect to all such matters  affecting such  Property,  such
                  Property   shall   be   excluded   from   the    transaction
                  contemplated   hereby,  and  the  Purchase  Price  shall  be
                  reduced by the amount  attributed  on Exhibit B to the wells
                  located  on  such  Property  and the  units  in  which  such
                  Property participates.

            (b) The Properties with Asserted  Defects for which Seller and Buyer
      agree on a  valuation  adjustment  pursuant  to Section  8(a)(i)  shall be
      divided into two groups.  The first group ("Major  Defects") shall contain
      the Properties with valuation  adjustments  which  individually  are in an
      amount  greater  than or equal  to  $250,000.  The  second  group  ("Minor
      Defects")  shall contain the Properties with valuation  adjustments  which
      individually are in an amount less than $250,000.  The Base Purchase Price
      shall be reduced by the total amount of the Major Defects. If the total of
      all Minor  Defects is greater than  $2,375,000,  the Base  Purchase  Price
      shall be reduced by the total amount of the Minor Defects. If the total of
      all Minor Defects is less than  $2,375,000,  the Base Purchase Price shall
      not be reduced.

            (c) If Seller is shown to be entitled  to a share of the  production
      from a well or unit  listed on Exhibit B greater  than the share shown for
      such well or unit  under the  column  headed  "Net  Revenue  Interest"  on
      Exhibit B, then Seller may propose an increase in the Purchase  Price,  in
      which case such  increase  shall be handled in the same manner as provided
      in Sections 8 (a) and (b) above with respect to  adjustments  for Asserted
      Defects  except  that the Base  Purchase  Price shall be  increased;  and,
      provided that the party making such  determination  shall notify the other
      party of such  adjustment no later than five (5) days prior to the Closing
      Date.

      9.    Conditions Precedent to Buyer's  Obligations.  Buyer's obligations
under this Agreement are subject to each of the following conditions:

            (a) Seller's  representations under this Agreement shall be true and
      accurate  in all  material  respects as of the date when made and shall be
      deemed  to  have  been  made  again  at  Closing.  At  Closing,   Seller's
      representations  under this  Agreement  shall be true and  accurate in all
      material respects except as to changes  specifically  contemplated by this
      Agreement or consented to by Buyer.

            (b)  Seller  shall  have  performed  and  complied  in all  material
      respects with every  covenant,  agreement,  and  condition  required by it
      under this  Agreement  prior to or at the Closing  unless  performance  or
      compliance therewith shall have been waived by Buyer.

            (c) If  applicable,  Buyer and Seller shall have  received  approval
      from the FTC under  the HSR Act of the  transaction  contemplated  by this
      Agreement,  or shall have received  notification  that the waiting  period
      under such act has been  terminated,  or the waiting period under such act
      shall have expired.

            (d) The Purchase  Price  increase  resulting  from the procedure set
      forth in Section 8 does not exceed five percent (5%) of the Base  Purchase
      Price.

            (e)  On the  Closing  Date,  no  material  suit,  action,  or  other
      proceeding against Buyer shall be pending before any court or governmental
      agency seeking to restrain, prohibit, or obtain damages or other relief in
      connection with the  consummation of the transaction  contemplated by this
      Agreement.

If any such condition precedent to the obligations of Buyer under this Agreement
is not met as of the Closing Date, and if Buyer is not in material breach of its
obligations hereunder,  this Agreement may be terminated at the option of Buyer.
If Buyer thus terminates  this Agreement,  the Deposit will be returned to Buyer
and the  parties  shall have no further  obligations  to one  another  hereunder
(other than the obligations under Sections  6(a)(iii) and 15 hereof,  which will
survive such  termination).  Notwithstanding  the foregoing,  if a condition set
forth above,  other than  condition 9(c) or 9(d), is not met (and is asserted by
Buyer as a failure of one of its conditions of Closing), and if the reasons such
condition  is not met  relate  only to  some,  but not all,  of the  Properties,
failure  of such  condition  to be met may,  at the  option of  either  Buyer or
Seller,  be treated as an uncured Asserted Defect and handled in accordance with
the process set forth in Section 8 above.

      10.   Conditions   Precedent   to   Seller's    Obligations.    Seller's
obligations  under this  Agreement  are  subject to the each of the  following
conditions:

            (a) Buyer's  representations  under this Agreement shall be true and
      accurate  in all  material  respects as of the date when made and shall be
      deemed  to  have  been  made  again  at  Closing.   At  Closing,   Buyer's
      representations  under this  Agreement  shall be true and  accurate in all
      material respects except as to changes  specifically  contemplated by this
      Agreement or consented to by Seller.

            (b) Buyer shall have performed and complied in all material respects
      with every covenant,  agreement,  and condition  required by it under this
      Agreement  prior to or at the Closing unless  compliance  therewith  shall
      have been waived by Seller.

            (c) If  applicable,  Buyer and Seller shall have  received  approval
      from the FTC under  the HSR Act of the  transaction  contemplated  by this
      Agreement,  or shall have received  notification  that the waiting  period
      under such act has been  terminated,  or the waiting period under such act
      shall have expired.

            (d) The Purchase  Price  reduction  resulting from the procedure set
      forth in  Section 8 above does not exceed  five  percent  (5%) of the Base
      Purchase Price.

            (e)  On the  Closing  Date,  no  material  suit,  action,  or  other
      proceeding   against   Seller  shall  be  pending   before  any  court  or
      governmental  agency seeking to restrain,  prohibit,  or obtain damages or
      other  relief  in  connection  with the  consummation  of the  transaction
      contemplated by this Agreement.

If any  such  condition  precedent  to the  obligations  of  Seller  under  this
Agreement is not met as of the Closing Date, this Agreement may be terminated at
the option of Seller.  If Seller  terminates  this Agreement  because of Buyer's
failure to fulfill  condition  (a) or (b),  the Deposit  will not be returned to
Buyer.  If Seller  terminates  this Agreement  because of conditions (c), (d) or
(e), and Buyer is not in material default under this Agreement, the deposit will
be  returned  to Buyer.  Thereafter  Seller  and  Buyer  shall  have no  further
obligations to one another  hereunder (other than the obligations  under Section
6(a)(iii) and 15 hereof, which will survive such termination).

      11. The Closing.  The consummation of the transaction  contemplated hereby
("Closing")  shall take place in the  offices of Seller,  at 6688 North  Central
Expressway,  Dallas,  Texas  75206,  on July 15,  1996,  at 10:00  a.m.  Central
Daylight  Time,  or at such  other date and time (i) as the Buyer and Seller may
agree or (ii) to which  Seller may  postpone  the Closing  pursuant to Section 7
hereof  (such date and time,  as changed  pursuant to clauses (i) and (ii) being
herein called the "Closing Date"). At the Closing:

            (a)   Seller shall:

            (i)   execute, acknowledge, and deliver to Buyer a conveyance of the
                  Properties (the  "Assignment  and Bill of Sale"),  in the form
                  attached  hereto  as  Exhibit C (with  Exhibit A hereto  being
                  attached thereto),  effective as to runs of oil and deliveries
                  of gas as of 7 o'clock  a.m.,  local time at the  locations of
                  the Properties, respectively, on April 1, 1996, (herein called
                  the "Effective Date"); and

            (ii)  execute  (and,  where  required,  acknowledge)  and deliver to
                  Buyer forms of  conveyance  or  assignment  as required by the
                  applicable  authorities for transfers of interests in state or
                  federal leases included in the Properties;

            (iii) execute  and  deliver  to Buyer  letters  in lieu of  transfer
                  orders (or similar documentation),  in form acceptable to both
                  parties; and

            (iv)  if Buyer  requests,  deliver to Buyer an  affidavit or other
                  certification  (as permitted by the Internal Revenue Code of
                  1986,  as  amended)  that  Seller is not a "foreign  person"
                  within the meaning of Section  1445 (or similar  provisions)
                  of such  code  (i.e.,  Seller is not a  non-resident  alien,
                  foreign corporation,  foreign partnership, foreign trust, or
                  foreign estate,  as those terms are defined in such code and
                  regulations promulgated thereunder); and

            (v)   to the extent Seller is able to do so, turn over  possession
                  of the Properties to Buyer.

            (b)   Buyer shall:

            (i)   deliver to the  Seller,  by wire  transfer  to an account in a
                  bank  located  in the  United  States  designated  to Buyer by
                  Seller in  writing  no later  than five (5) days  prior to the
                  Closing,  an amount equal to (A) the Purchase Price,  less (B)
                  the  Deposit,  less  (or  plus,  as the  case  may be) (C) any
                  adjustments made at Closing under Section 12 below; and

            (ii)  with respect to properties  operated by Seller, and subject to
                  applicable  Operating  Agreement  requirements,   execute  and
                  deliver to Seller  appropriate  evidence  reflecting change of
                  operator  as  required  by  applicable  authorities,  and such
                  evidence as Seller may require  that Buyer is  qualified  with
                  such authorities to succeed Seller as operator; and

            (iii) execute  such  forms and take such  other  steps as Seller may
                  reasonably  require to (i) succeed  Seller with respect to the
                  Properties  under  the  rules and  regulations  of  applicable
                  authorities and (ii) assume any plugging liabilities of Seller
                  with  respect  to the wells  located on the  Properties  or on
                  units in which the Properties participate (including,  without
                  limitation compliance with state statutes).

Within  fifteen (15) days after  Closing,  Seller shall  deliver to Buyer all of
Seller's  lease  files,  abstracts  and title  opinions,  division  order files,
production records,  well files, copies of accounting records (but not including
general financial accounting or tax accounting records), and other similar files
and  records  that  directly  relate  to  the  Properties.  Notwithstanding  the
foregoing,  Seller  shall not be  required  to deliver to Buyer  materials  that
Seller  considers  proprietary  or  confidential  or that Seller  legally cannot
provide to Buyer  without,  in its opinion,  breaching,  or risking a breach of,
confidentiality  agreements with other parties. It is expressly  understood that
Buyer is not  acquiring,  and Seller is not obligated to transfer to Buyer,  any
seismic  data,  geological  or  geophysical  data, or other similar data, or any
interpretations  thereof  or other  data or records  related  thereto  except as
provided in Section 1 herein.  With  respect to each  portion of the  Properties
from which Seller is  disbursing  proceeds of production  attributable  to other
parties:

            (i)   Seller  shall  continue to collect  proceeds  of  production
                  through  the  production  month of July  1996,  and shall be
                  responsible  for making  disbursements,  in accordance  with
                  its  normal  procedures  (and  at  normal  times),  of  such
                  proceeds of production so collected to the parties  entitled
                  to  same,   with  any  proceeds  of  production   thereafter
                  collected by Seller to be  forwarded  promptly to Buyer (who
                  shall  thereafter  account for same to the parties  entitled
                  thereto), and

            (ii)  After  execution of this  Agreement,  but no later than five
                  (5) days before the Closing  Date,  Seller shall  deliver to
                  Buyer (A) a copy of its "pay  list"  for each such  property
                  (which  pay list shall  include  the name,  address,  social
                  security   number  and  applicable   share  of  proceeds  of
                  production,  to the extent such  information is contained in
                  Seller's   records,   for  each  party  to  whom  Seller  is
                  disbursing  proceeds  of  production  with  respect  to such
                  property),  and (B) a list  of all  parties  for  whom it is
                  holding in suspense proceeds of production.

Following  delivery of the  materials  referred  to in clause (ii) above,  Buyer
shall  become  responsible  for all  disbursements  of  proceeds  of  production
commencing  with the  production  month of August  1996,  and such  disbursement
activities  shall be included in the matters that Buyer assumes and with respect
to which Buyer  indemnities  Seller under Section 13 below. It is understood and
agreed that Seller does not  represent  or warrant to Buyer the  accuracy of the
"pay lists" so delivered.

Buyer and Seller shall  cooperate  with respect to  transition  activities as to
Properties  where Buyer succeeds  Seller as operator.  SELLER GIVES NO ASSURANCE
HEREUNDER  THAT BUYER SHALL  SUCCEED  SELLER AS OPERATOR OF ANY  PROPERTY  WHERE
PARTIES OTHER THAN SELLER OWN INTERESTS IN SUCH  PROPERTY.  To the extent Seller
remains an operator  after Closing (which it shall have no obligation to do), it
shall serve as operator under the applicable  operating  agreement in the manner
provided by such  agreement  and, to the extent  Seller so operates any Property
after Closing, its obligations to Buyer with respect to such operations shall be
no greater than those that it would have to a non-operator  under the applicable
operating  agreement (and, in the absence of an operating  agreement,  under the
AAPL 610 (1989 Revision) form Operating  Agreement).  THE PARTIES RECOGNIZE THAT
UNDER SUCH AGREEMENTS AND SUCH FORM OF AGREEMENT THE OPERATOR IS NOT RESPONSIBLE
TO THE OTHER PARTIES THERETO FOR ITS OWN NEGLIGENCE AND HAS NO RESPONSIBILITY TO
SUCH OTHER PARTIES OTHER THAN FOR GROSS NEGLIGENCE OR WILLFUL MISCONDUCT. SELLER
INDEMNIFIES  AND AGREES TO DEFEND BUYER AGAINST CLAIMS THAT RESULT FROM SELLER'S
ACTS THAT ARE HELD IN A FINAL AND UNAPPEALABLE  DECISION BY A COURT OF COMPETENT
JURISDICTION  TO HAVE BEEN  CONDUCTED IN A GROSSLY  NEGLIGENT  MANNER OR TO HAVE
RESULTED FROM THE WILLFUL MISCONDUCT OF SELLER.  Seller agrees that, with regard
to the period  between the  Effective  Date and the Closing Date, if Seller does
not properly distribute proceeds of production from the Properties in accordance
with its duties  under the  applicable  contracts,  and if this  failure  causes
penalties  to be imposed on Seller or Buyer,  Seller shall bear the cost of such
penalties.

      12.   Certain Accounting Adjustments.

            (a)   Appropriate  adjustments  shall be made  between  Buyer  and
      Seller so that:

            (i)   all expenses  (including,  without limitation,  all drilling
                  costs, all capital expenditures,  all overhead charges under
                  applicable operating agreements,  regardless of whether such
                  operating  agreements  are with  third  parties  or  related
                  entities,  and  regardless of whether Seller is the operator
                  or a non-operator)  and all other overhead  charges actually
                  charged by third  parties and  incurred in the  operation of
                  the  Properties  after the Effective Date shall be allocated
                  to Buyer,  and all proceeds (net of  applicable  production,
                  severance,  and similar  taxes) from sale of oil,  gas,  and
                  other  minerals  produced  from  the  Properties  after  the
                  Effective Date shall be allocated to Buyer; and

            (ii)  all  expenses  incurred  in the  operation  of the  Properties
                  before the  Effective  Date shall be allocated to Seller,  and
                  all proceeds (net of  applicable  production,  severance,  and
                  similar  taxes) from the sale of oil, gas, and other  minerals
                  produced from the  Properties  before the Effective Date shall
                  be allocated to Seller.

In making such adjustments, the parties agree that:

            (i)   oil above  pipeline  connections  that was  produced  from the
                  Properties  and  that  was  stored  in  tanks  located  on the
                  Properties  on the  Effective  Date (or located  elsewhere but
                  used by Seller to store oil produced from the Properties prior
                  to delivery to oil purchasers) and above pipeline  connections
                  shall be deemed to have been  produced  before  the  Effective
                  Date; and

            (ii)  ad valorem and similar  taxes  assessed for periods prior to
                  the Effective Date shall be borne by Seller,  and ad valorem
                  taxes  assessed for periods on or after the  Effective  Date
                  shall be borne by Buyer (ad valorem and similar  taxes shall
                  be  considered  assessed  for the  period for which they are
                  stated  to be  assessed,  even  if the  same  are  based  on
                  production or other activities  occurring in prior periods);
                  and

            (iii) ad valorem  taxes with  respect to the period  containing  the
                  Effective  Date  shall be  prorated  between  Buyer and Seller
                  based on the number of days in such  period  that fall  before
                  and after the Effective  Date (with the  Effective  Date being
                  counted in the period after the Effective Date); and

            (iv)  no  consideration  shall  be  given to the  local,  state,  or
                  federal income tax liabilities of any party.

            (b) In  addition,  Buyer and Seller  shall  determine  (i) the total
      amount of  overproduction  of gas  (measured  in Mcf) with  respect to the
      Properties as of the Effective Date (e.g.  volumes of gas taken from wells
      on the Properties,  or on lands unitized  therewith,  by the owners of the
      Properties  in  excess  of  those  volumes  which  the  ownership  of  the
      Properties  would entitle such owners to receive) and (ii) total amount of
      underproduction of gas (measured in Mcf) with respect to the Properties as
      of the  Effective  Date  (e.g.  the amount by which the volume of gas from
      wells  on the  Properties,  or on  lands  unitized  therewith,  which  the
      ownership  of the  Properties  would  entitle  the owners  thereof to take
      exceeds the volumes taken from such wells by owners).  If the total amount
      of overproduction exceeds the total amount of underproduction, Buyer shall
      be credited with an amount equal to $1.00 times such excess.  If the total
      amount of  underproduction  exceeds  the total  amount of  overproduction,
      Seller shall be credited  with an amount equal to $1.00 times such excess.
      Buyer and Seller  shall also  determine  the  amount of all  pipeline  and
      gathering  system  imbalances  that existed as of the Effective  Date with
      respect to deliveries from the Properties. Seller shall receive credit for
      all  benefits  arising out of such  imbalances,  and Buyer  shall  receive
      credit for all obligations arising out of such imbalances.

            (c) At or before Closing,  the parties shall  determine,  based upon
      the best information  reasonably  available to them (and as to adjustments
      under subsection (a), based on amounts actually received or paid by Seller
      prior  to  such  time)  the  amount  of the  adjustments  provided  for in
      subsections  (a) and (b) above. If the amount of adjustments so determined
      that would result in a credit to Buyer  exceeds the amount of  adjustments
      so determined that would result in a credit to Seller, Buyer shall receive
      a credit for the amount of such excess.  If the amount of  adjustments  so
      determined  that would  result in a credit to Seller  exceed the amount of
      adjustments  so determined  that would result in a credit to Buyer,  Buyer
      shall pay to Seller the amount of such  excess.  On or before one  hundred
      twenty  (120)  days  after  Closing,  Buyer and  Seller  shall  review any
      additional  information  pertaining  to the  adjustments  provided  for in
      subsections  (a)  and  (b)  above,   shall  determine  if  any  additional
      adjustments (whether the same be made to account for expenses or revenues,
      or overproduction or underproduction volumes, not considered in making the
      adjustments   made  at  Closing,   or  to  correct  errors  made  in  such
      adjustments)  should be made beyond those made at Closing,  and shall make
      any such adjustments by appropriate  payments from Seller to Buyer or from
      Buyer  to  Seller.  Following  such  additional  adjustments,  no  further
      adjustments shall be made under this Section 12.

      13. Assumption and  Indemnification.  Buyer shall, on the date of Closing,
agree (and,  upon the delivery to Buyer of the Assignment and Bill of Sale shall
be deemed to have  agreed)  (a) to assume,  and timely to pay and  perform,  all
duties,  obligations and  liabilities  relating to the ownership or operation of
the Properties after the Effective Date (including,  without  limitation,  those
arising under the contracts and agreements described in Section 1(c) above), and
(b) to release,  indemnify,  defend, and hold harmless the Seller Group from and
against any and all claims,  actions,  liabilities,  losses,  damages,  costs or
expenses  (including  court costs and attorneys'  fees) of any kind or character
arising  out of or  otherwise  relating to the  ownership  or  operation  of the
Properties  after the Effective  Date. In connection with (but not in limitation
of) the foregoing, it is specifically understood and agreed that matters arising
out of or otherwise  relating to the  ownership  or operation of the  Properties
after the Effective  Date shall be deemed to include all matters  arising out of
the  condition  of the  Properties  on the  Effective  Date  including,  without
limitation,  within such matters all  obligations  to properly  plug and abandon
wells located on the Properties, to restore the surface of the Properties and to
comply  with,  or  bring  the  Properties  into  compliance   with,   applicable
environmental  laws,  including all  liability and expense for any  restoration,
clean-up, disposal, or removal that may be incurred as a result of the existence
or discovery of Hazardous Substances or other deleterious  substances in, on, or
under the  Properties,  regardless of when the events occurred that give rise to
such condition,  and the above provided for assumptions and  indemnifications by
Buyer shall expressly cover and include such matters. THE FOREGOING  ASSUMPTIONS
AND  INDEMNIFICATIONS  SHALL APPLY WHETHER OR NOT SUCH DUTIES,  OBLIGATIONS,  OR
LIABILITIES,  OR SUCH CLAIMS, ACTIONS, CAUSES OF ACTION,  LIABILITIES,  DAMAGES,
LOSSES,  COSTS,  OR  EXPENSES  ARISE  OUT  OF  (i)  NEGLIGENCE  (INCLUDING  SOLE
NEGLIGENCE,   SINGLE  NEGLIGENCE,   CONCURRENT  NEGLIGENCE,  ACTIVE  OR  PASSIVE
NEGLIGENCE,  BUT EXPRESSLY NOT INCLUDING GROSS NEGLIGENCE OR WILLFUL MISCONDUCT)
OF SELLER OR ANY OTHER INDEMNIFIED PARTY, OR (ii) STRICT LIABILITY. Seller shall
give notice to Buyer of an event giving rise to the obligation to indemnify, and
Seller shall, at its sole cost and expense,  have the right, if it so elects, to
participate in the defense of any such suit or suits in which it may be a party,
without relieving Buyer of its obligation.

      14. Disclaimer of Warranties.  THE EXPRESS  REPRESENTATIONS AND WARRANTIES
OF SELLER CONTAINED IN SECTION 4 (OR IN THE ASSIGNMENT AND BILL OF SALE EXECUTED
PURSUANT  TO  THIS  AGREEMENT)  ARE  EXCLUSIVE  AND  ARE IN  LIEU  OF ALL  OTHER
REPRESENTATIONS  AND  WARRANTIES,  EXPRESS,  IMPLIED,  STATUTORY,  OR OTHERWISE,
EXCEPT FOR A SPECIAL  WARRANTY  OF TITLE AS  HEREINAFTER  DESCRIBED,  AND SELLER
EXPRESSLY  DISCLAIMS  ANY AND ALL SUCH  OTHER  REPRESENTATIONS  AND  WARRANTIES.
WITHOUT  LIMITATION OF THE FOREGOING,  THE PROPERTIES SHALL BE CONVEYED PURSUANT
HERETO  WITHOUT  ANY  WARRANTY  OR  REPRESENTATION,  WHETHER  EXPRESS,  IMPLIED,
STATUTORY, OR OTHERWISE RELATING TO THE CONDITION,  QUANTITY,  QUALITY,  FITNESS
FOR A PARTICULAR PURPOSE,  CONFORMITY TO THE MODELS OR SAMPLES OF MATERILALS, OR
MERCHANTABILITY OF ANY EQUIPMENT OR ITS FITNESS FOR ANY PURPOSE,  AND, EXCEPT AS
PROVIDED  OTHERWISE IN THE FIRST SENTENCE OF THIS  PARAGRAPH,  WITHOUT ANY OTHER
EXPRESS,  IMPLIED,  STATUTORY,  OR OTHER WARRANTY OR REPRESENTATION  WHATSOEVER.
BUYER SHALL HAVE INSPECTED,  OR WAIVED (AND UPON CLOSING SHALL BE DEEMED TO HAVE
WAIVED) ITS RIGHT TO INSPECT,  THE  PROPERTIES  FOR ALL PURPOSES  AND  SATISFIED
ITSELF AS TO THEIR  PHYSICAL  AND  ENVIRONMENTAL  CONDITION,  BOTH  SURFACE  AND
SUBSURFACE,  INCLUDING,  BUT NOT LIMITED TO, CONDITIONS  SPECIFICALLY RELATED TO
THE  PRESENCE,  RELEASE,  OR DISPOSAL OF  HAZARDOUS  SUBSTANCES,  SOLID  WASTES,
ASBESTOS OR OTHER MANMADE FIBERS OR NATURALLY  OCCURRING  RADIOACTIVE  MATERIALS
("NORM") IN, ON, OR UNDER THE  PROPERTIES.  BUYER IS RELYING SOLELY UPON ITS OWN
INSPECTION  OF THE  PROPERTIES,  AND BUYER SHALL,  EXCEPT AS PROVIDED  OTHERWISE
HEREIN,  ACCEPT  ALL OF THE SAME "AS IS,  WHERE IS"  WITHOUT  LIMITATION  OF THE
FOREGOING,  SELLER  MAKES  NO  WARRANTY  OR  REPRESENTATION,  EXPRESS,  IMPLIED,
STATUTORY,  OR  OTHERWISE,  AS TO THE  ACCURACY  OR  COMPLETENESS  OF ANY  DATA,
REPORTS,  RECORDS,  PROJECTIONS,  INFORMATION,  OR MATERIALS NOW, HERETOFORE, OR
HEREAFTER FURNISHED OR MADE AVAILABLE TO BUYER IN CONNECTION WITH THIS AGREEMENT
INCLUDING,  WITHOUT  LIMITATION,  PRICING  ASSUMPTIONS OR QUALITY OR QUANTITY OF
HYDROCARBON  RESERVES (IF ANY)  ATTRIBUTABLE TO THE PROPERTIES OR THE ABILITY OR
POTENTIAL  OF THE  PROPERTIES  TO  PRODUCE  HYDROCARBONS  OR  THE  ENVIRONMENTAL
CONDITION OF THE  PROPERTIES OR ANY OTHER MATTERS  CONTAINED IN THE  PROPRIETARY
DATA OR ANY OTHER MATERIALS FURNISHED OR MADE AVAILABLE TO BUYER BY SELLER OR BY
SELLER'S AGENTS OR  REPRESENTATIVES.  ANY AND ALL SUCH DATA,  RECORDS,  REPORTS,
PROJECTIONS,  INFORMATION,  AND OTHER  MATERIALS  (WRITTEN OR ORAL) FURNISHED BY
SELLER OR OTHERWISE  MADE  AVAILABLE OR DISCLOSED TO BUYER ARE PROVIDED TO BUYER
AS A  CONVENIENCE  AND SHALL NOT  CREATE  OR GIVE  RISE TO ANY  LIABILITY  OF OR
AGAINST SELLER,  AND ANY RELIANCE ON OR USE OF THE SAME SHALL BE AT BUYER'S SOLE
RISK TO THE MAXIMUM EXTENT PERMITTED BY LAW.

      TO THE EXTENT OF SELLER'S  INTEREST IN THE  PROPERTIES AS SHOWN ON EXHIBIT
B, SELLER  WARRANTS  TITLE BY, THROUGH AND UNDER SELLER,  BUT NOT OTHERWISE,  IT
BEING  EXPRESSLY  UNDERSTOOD  THAT THE  TERM  "SELLER"  AS USED IN THIS  SPECIAL
WARRANTY  PROVISION  REFERS  TO  ENSERCH  EXPLORATION,   INC.  AND  NOT  TO  ITS
PREDECESSORS IN TITLE INCLUDING,  BUT NOT LIMITED TO, DALEN  CORPORATION,  DALEN
RESOURCES OIL & GAS CO., PG&E RESOURCES  COMPANY,  PG&E  ENTERPRISES AND EACH OF
THEIR PREDECESSORS. THIS SPECIAL WARRANTY SHALL NOT COVER OR PERTAIN TO TITLE AS
IT MAY BE  AFFECTED  BY THAT  CERTAIN  ASSIGNMENT  OF OIL AND  GAS  LEASES  WITH
RESERVATION  OF PRODUCTION  PAYMENT,  DATED  EFFECTIVE  AUGUST 1, 1995,  BETWEEN
SELLER AND TGAS INVESTMENTS L.L.C.

      15.  Commissions.  Seller agrees to indemnify and hold harmless Buyer, its
parent and  subsidiary  companies  and other  affiliates,  and their  directors,
officers, employees and agents from and against any and all claims, obligations,
actions, liabilities, losses, damages, costs, or expenses (including court costs
and attorneys  fees) of any kind or character  arising out of or resulting  from
any agreement,  arrangement,  or understanding  by, or on behalf of, Seller with
any  broker or finder in  connection  with  this  Agreement  or the  transaction
contemplated  hereby.  Buyer agrees to indemnify and hold harmless  Seller Group
from and against any and all claims, obligations,  actions, liabilities, losses,
damages,  costs, or expenses  (including  court costs and reasonable  attorney's
fees) of any kind or character  arising out of or resulting  from any agreement,
arrangement,  or  understanding  by, or on behalf  of,  Buyer with any broker or
finder in connection with this Agreement or the transaction contemplated hereby.

      16. Casualty Loss. If the Properties are damaged by fire or other casualty
prior to the Closing,  this Agreement shall remain in full force and effect, and
(unless  Buyer and Seller shall  otherwise  agree) in such event as to each such
damaged  Property  that Seller,  in its sole  discretion,  elects not to repair,
Buyer  either may treat such  Property as if it had an Asserted  Defect or elect
not to adjust the Purchase Price  therefor.  If Buyer elects  hereunder to treat
the damaged Property as if it had an Asserted Defect, the procedure provided for
in Section 8 shall apply to such Property,  and all rights to insurance proceeds
and claims  against third  parties  related  thereto shall belong to Seller.  If
Buyer  elects  hereunder  not to adjust  the  Purchase  Price  for such  damaged
Property, and if Seller is entitled to any claims under an insurance policy with
respect to such damage,  Seller shall  either  collect and pay over,  or assign,
such  insurance  claims to Buyer.  Buyer shall then take title to such  Property
without  reduction of the Purchase  Price.  If Seller elects to repair a damaged
Property,  all rights to insurance  proceeds and claims  against  third  parties
related thereto shall belong to Seller.

      17. Notices.  All notices and other  communications  required or permitted
under this Agreement shall be in writing, unless otherwise specifically provided
herein, and shall be delivered  personally,  by recognized commercial courier or
delivery  service  (which  provides a  receipt),  by telex or  telecopier  (with
receipt acknowledged),  or by registered or certified mail (postage prepaid), at
the following addresses:

      If to Buyer:

            Abraxas Petroleum Corporation
            500 North Loop 1604 East
            Suite 100
            San Antonio, Texas 78232
            Attention:  Mr. Robert L. G. Watson






      With a copy to:

            Cox & Smith Incorporated
            112 East Pecan Street
            Suite 1800
            San Antonio, Texas 78205
            Attention:  Mr. Steven R. Jacobs

      If to Seller:
            Enserch Exploration, Inc.
            4849 Greenville Avenue
            Suite 1200
            Dallas, Texas 75206
            Attention: Mr. James Hyink

      With a copy to:
            Mr. Randall B. Wilson
            Vice President and General Counsel Enserch Exploration, Inc.
            6688 North Central Expressway Suite 1000
            Dallas, Texas 75206

All such notices and communications shall be considered delivered on the date of
receipt. Buyer or Seller may specify as its proper address any other post office
address within the  continental  limits of the United States by giving notice to
the other party, in the manner provided in this Section.

      18.  Survival of Provisions.  All  representations  and warranties made in
Section 4 by Seller and in Section 5 by Buyer shall be  continuing  and shall be
true and correct on the  Closing  Date with the same force and effect as if made
at that time (and shall inure to the benefit of the  respective  successors  and
assigns of Buyer and Seller).  All such  representations  and  warranties  shall
survive the Closing and the  delivery of the  Assignment  and Bill of Sale.  The
obligations  of the  parties  under  Section 11 (to the extent the same are,  by
mutual  agreement,  not performed at Closing),  and Sections 12, 13, 14, 15, 17,
18, and 19 shall (subject to any limitations set forth therein) also survive the
Closing and the delivery of the Assignment and Bill of Sale.

      19.   Miscellaneous Matters.

            (a) After the Closing,  Seller and Buyer shall  execute and deliver,
      and shall otherwise cause to be executed and delivered, from time to time,
      such further instruments,  notices,  division orders, transfer orders, and
      other  documents,  and do such other and further acts and things as may be
      reasonably  necessary  more fully and  effectively to grant,  convey,  and
      assign the Property to Buyer.  Seller  shall  prepare and Buyer shall file
      appropriate  assignments and other documents  required for the transfer of
      any federal leases  comprising a portion of the Properties.  Seller agrees
      that until  governmental  approval of each such  assignment  is  obtained,
      Seller shall forward to Buyer notices that Seller receives  regarding such
      leases and Seller  agrees to  cooperate  with  Buyer in  maintaining  such
      leases in effect. At the request of Buyer,  Seller agrees to name Buyer as
      its designated operator for any federal leases which comprise a portion of
      the Properties.

            (b) Except as provided below,  neither party shall have the right to
      assign its rights under this Agreement  without the prior written  consent
      of the other party, and any such assignment in violation of this provision
      shall be void. Seller may, without consent,  assign its rights to a direct
      or  indirect  parent of  Seller,  to a direct or  indirect  subsidiary  of
      Seller,  or to an entity  that is a direct  or  indirect  subsidiary  of a
      direct or indirect parent of Seller.

            (c) On the  Closing  Date  (and  upon the  delivery  to Buyer of the
      Assignment  and Bill of Sale),  Buyer  shall  succeed to the  position  of
      Seller with respect to all gas imbalances  (whether wellhead imbalances or
      pipeline  or  gathering  imbalances)  and to the  position  of Seller with
      respect to all make-up obligations. As a result of such succession,  Buyer
      (i) shall be entitled to receive any and all benefits,  including payments
      of proceeds of production in excess of amounts that it would  otherwise be
      entitled to produce and receive by virtue of ownership  of the  Properties
      that Seller would have been entitled to receive by virtue of such position
      and (ii) shall be obligated to suffer any detriments  (whether the same be
      in the form of obligations to deliver production that would have otherwise
      been  attributable  to its ownership of the Properties  without  receiving
      full payment therefor, or be in the form of the obligation to make payment
      in cash) that Seller would have been obligated to suffer by virtue of such
      positions.

            (d) To the extent applicable to the transaction contemplated hereby,
      or any portion thereof, Buyer waives the provisions of the Texas Deceptive
      Trade  Practices  Act,  Chapter 17,  Subchapter E, Sections  17.41 through
      17.63,  inclusive  (other than Section 17.555 which is not waived),  Texas
      Business and Commerce Code. In connection  with such waiver,  Buyer hereby
      represents  and  warrants to Seller  that Buyer (a) is in the  business of
      seeking  or  acquiring,  by  purchase  or  lease,  goods or  services  for
      commercial  or  business  use,  (b) has assets of Five  Million and No/100
      Dollars  ($5,000,000.00)  or more  according to its most recent  financial
      statement,  (c) has  knowledge  and  experience  in financial and business
      matters that enable it to evaluate the merits and risks of the transaction
      contemplated  hereby,  and  (d)  is  not  in  a  significantly   disparate
      bargaining position.

            (e) Any  Confidentiality  Agreement  executed by Buyer and Seller in
      connection with the transaction  contemplated hereby remains in full force
      and effect and is not superseded or modified by this Agreement.

            (f) This Agreement contains the entire  understanding of the parties
      hereto with  respect to subject  matter  hereof and  supersedes  all prior
      agreements,  understandings,   negotiations,  and  discussions  among  the
      parties with respect to such subject matter, except as provided above with
      respect to any Confidentiality  Agreement.  The headings contained in this
      Agreement  are for  convenience  only and shall not  control or affect the
      meaning or construction  of any provision of this  Agreement.  Within this
      Agreement,  words of any gender  shall be held and  construed to cover any
      other  gender,  and words in the singular  shall be held and  construed to
      cover the plural,  unless the context otherwise  requires.  Time is of the
      essence in this Agreement.

            (g) This Agreement may be amended, modified, supplemented, restated,
      or discharged (and provisions  hereof may be waived) only by an instrument
      in writing signed by the party against whom  enforcement of the amendment,
      modification, supplement, restatement, or discharge (or waiver) is sought.

            (h) Each  party  shall  bear and pay all  expenses  it  incurred  in
      connection with the transaction contemplated by this Agreement.

            (i) This Agreement  shall be binding on the parties hereto and their
      respective successors and assigns.

            (j) This Agreement may be executed in two or more counterparts, each
      of which shall be deemed an  original,  but all of which shall  constitute
      one and the same instrument. It shall not be necessary for both parties to
      sign the same counterpart.

            (k) WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAW, THIS AGREEMENT
      SHALL BE  CONSTRUED  AND ENFORCED IN  ACCORDANCE  WITH AND GOVERNED BY THE
      LAWS  OF THE  STATE  OF  TEXAS  APPLICABLE  TO  CONTRACTS  MADE  AND TO BE
      PERFORMED  ENTIRELY WITHIN SUCH STATE AND BY THE LAWS OF THE UNITED STATES
      OF  AMERICA,  EXCEPT  THAT,  TO THE EXTENT THE LAW OF A STATE IN WHICH THE
      PROPERTIES ARE LOCATED NECESSARILY  GOVERNS,  THE LAW OF SUCH STATE SHALL,
      TO SUCH EXTENT, APPLY TO THE PROPERTIES.

            (1) Prior to Closing,  Buyer shall not issue public announcements of
      this  Agreement  or the  transaction  described  herein  without the prior
      written  consent of Seller,  provided  however,  the  foregoing  shall not
      restrict disclosures by Buyer which, in the written opinion of third party
      legal counsel acceptable to Seller (Cox & Smith Incorporated, San Antonio,
      Texas,  is  acknowledged  to be  acceptable)  are  required to comply with
      applicable securities or other laws or are required to maintain compliance
      with  existing  loan  or  other  agreements  binding  such  party  (or its
      affiliated companies). Such required public announcements shall be limited
      to the minimum  information and  circulation  necessary to comply with the
      disclosure obligation.  Buyer and Seller agree that a Press Release in the
      form of Exhibit E, attached hereto, may be issued by Buyer after execution
      of this Agreement by Buyer and Seller.

      IN WITNESS  WHEREOF,  this  Agreement is executed by the parties hereto on
the date set forth above.

      ENSERCH EXPLORATION, INC.

      By: ________________________
          Barry K. Irani
          Senior Vice President

      ABRAXAS PETROLEUM CORPORATION

      By: ________________________
          Chris E. Williford
          Executive Vice President & Chief Financial Officer






                               ACKNOWLEDGEMENTS

STATE OF TEXAS

COUNTY OF DALLAS

      This instrument was acknowledged  before me, Notary Public, this _____ day
of  ______________,  1996, by Barry K. Irani,  Senior Vice  President of ENSERCH
EXPLORATION, INC., a Texas corporation, on behalf of the corporation.

      IN WITNESS WHEREOF, I hereunto set my hand and official seal.




                              Notary Public

My commission expires:




STATE OF TEXAS

COUNTY OF DALLAS

     This instrument was acknowledged  before me, Notary Public,  this _____ day
of__________  , 1996, by Chris E.  Williford,  Executive  Vice President & Chief
Financial Officer of ABRAXAS PETROLEUM  CORPORATION,  a Nevada  corporation,  on
behalf of the corporation.

      IN WITNESS WHEREOF, I hereunto set my hand and official seal.



                              _______________________________
                              Notary Public

My commission expires:

__________________________








0135685.01
                                                     EXHIBIT "A"


LEASE EXHIBIT


                                      LEASE
PROSPECT.......   ST.. COUNTY........ NUMBER...... LEASE NAME............ LESSEE.................  REC BOOK.. PAGE.....
                                                                                         
CRESTON........   WY   CARBON         493107       USA W 38437            GORDON TANNER
CRESTON .......   WY   CARBON         493108       USA W 57177            ROBERT J CONNAGHAN            724   335
WAMSUTTER NE ..   WY   SWEETWATER     493006       USA W 10054            ORVILLE HAER                  743   604
WAMSUTTER NE ..   WY   SWEETWATER     493007       USA W 12480            JOYCE A. EVANS                689   299
WAMSUTTER NE ..   WY   SWEETWATER     493008       USA W 16350            J L FUSSELMAN                 696   237
WAMSUTTER NE ..   WY   CARBON         493011       USA W 32958            WILLIAM C ARMOR JR            688   889
WAMSUTTER NE ..   WY   CARBON         493012       USA W 37181            BASIL P ANDRIKPOULOS          766   332
WAMSUTTER NE ..   WY   SWEETWATER     493013       USA W 37184            CHARLES E STRANGE JR          737   1825
WAMSUTTER NE ..   WY   CARBON         493014       USA W 38447            ROSE ROUX                     688   896
WAMSUTTER NE ..   WY   SWEETWATER     493015       USA W 54410            CARL M BOMHOLT                742   1290
WAMSUTTER NE ..   WY   CARBON         493016       ST WY 727052           GRETCHEN S CATRON             766   739
WAMSUTTER NE ..   WY   SWEETWATER     493017       ST WY 73 13620         VIRGINIA G STOUFFER           689   287
WAMSUTTER NE ..   WY   SWEETWATER     493018       CHAMPLIN PETROLEUM     AMOCO PRODUCTION              657   110
                                                   COMPANY                COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     493019       CHAMPLIN PETROLEUM     AMOCO PRODUCTION              615   116
                                                   COMPANY                COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     493240       USA WYW 115283         NGC ENERGY COMPANY            831   279
WAMSUTTER NE ..   WY   SWEETWATER     493690       USA WYW 124394         PG&E RESOURCES COMPANY        870   908
WAMSUTTER NE ..   WY   SWEETWATER     493699       USA WYW 124928         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     WY3758       UNION PACIFIC          PG&E RESOURCES COMPANY        846   127
                                                   RESOURCES CO



                                                  PAGE 1 of 2




ROW EXHIBIT



                                      LEASE
PROSPECT.......   ST.. COUNTY........ NUMBER ..... LEASE NAME............ LESSEE.................. REC BOOK.. PAGE.....
                                                                                         
WAMSUTTER NE ..   WY   SWEETWATER     493610       UNION PACIFIC LAND     PACIFIC TRANSMISSION
WAMSUTTER NE ..   WY   SWEETWATER     493613       UNION PACIFIC          NGC ENERGY COMPANY
                                                   RESOURCES CO
WAMSUTTER NE ..   WY   CARBON         493614       DOM ECHEVERRIA ESTATE  PTS
WAMSUTTER NE ..   WY   CARBON         493615       DOM ECHEVERRIA ESTATE  PACIFIC TRANSMISSION
                                                                          SUPPLY CO
WAMSUTTER NE ..   WY   SWEETWATER     493616       DOM ECHEVERRIA ESTATE  PACIFIC TRANSMISSION
WAMSUTTER NE ..   WY   SWEETWATER     493617       USA W 80301            NGC ENERGY COMPANY
WAMSUTTER NE ..   WY   CARBON         493618       DOM ECHEVERRIA TRUST   NGC ENERGY COMPANY
WAMSUTTER NE ..   WY   CARBON         493619       DOM ECHEVERRIA TRUST   NGC ENERGY COMPANY
WAMSUTTER NE ..   WY   CARBON         493620       DOM ECHEVERRIA TRUST   PACIFIC TRANSMISSION
                                                                          SUPPLY
WAMSUTTER NE ..   WY   SWEETWATER     493621       P&H LIVESTOCK COMPANY  PACIFIC TRANSMISSION
                                                                          SUPPLY
WAMSUTTER NE ..   WY   SWEETWATER     493622       P H LIVESTOCK COMPANY  NGC ENERGY COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     493623       USA W 93669            NGC ENERGY COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     493625       USA W 88986            NGC
WAMSUTTER NE ..   WY   CARBON         493644       USA WYW 117008         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     493646       USA WYW 117001         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   CARBON         493681       USA WYW 119066         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1008   UNION PACIFIC LAND     PG&E RESOURCES COMPANY
                                                   RESOURCES
WAMSUTTER NE ..   WY   CARBON         7-491-1019   NORWEST BANK GREELEY   PG&E RESOURCES COMPANY
                                                   NATL ASSO
WAMSUTTER NE ..   WY   CARBON         7-491-1020   NORWEST BANK GREELEY   PG&E RESOURCES COMPANY
                                                   NATL ASSO
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1023   USA WYW 128278         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1024   USA WYW 127932         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1026   UNION PACIFIC LAND     PG&E RESOURCES COMPANY        838   614
                                                   RESOURCES
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1027   UNION PACIFIC LAND     PG&E RESOURCES COMPANY        838   609
                                                   RESOURCES CO
WAMSUTTER NE ..   WY   CARBON         7-491-1028   USA WYW 128279         PG&E RESOURCES COMPANY
WAMSUTTER NE ..   WY   SWEETWATER     7-491-1036   UNION PACIFIC LAND     PG&E RESOURCES COMPANY        846   859
                                                   RESOURCES



                                  PAGE 2 of 2









                                   
                                                     EXHIBIT B
- ------------------------------------------------------------------------------------------------------------------------
                                                                                       B.P.O.                A.P.O.       ALLOCATED

                                                                                ---------------------  -----------------
API         WELL    WELL NAME                     COUNTY      ST  FIELD NAME      G.W.I.     N.R.I.    G.W.I.     N.R.I.     VALUE
NUMBER      ID
- ------------------------------------------------------------------------------------------------------------ -----------  ----------
                                                                                            
4900721150  4833  ECHO SPRINGS #3X-36A            CARBON      WY  WAMSUTTER NE  1.0000000  .8450000  1.00000000  .8450000 $2,473,574
4903721427  4835  FIVE MILE GULCH #9              SWEETWATER  WY  WAMSUTTER NE  0.1575000  .1295990   .14062500  .1160157    $13,992
4903720828  4836  MONUMENT LAKE #1                SWEETWATER  WY  WAMSUTTER NE  0.5000000  .4093750   .50000000  .4093750     $9,240
4900721155  4837  ECHO SPRINGS #23-10 FED         CARBON      WY  WAMSUTTER NE  1.0000000  .8250001   .00000000  .8250000   $257,806
4903722126  4839  SOURDOUGH GULCH #3-5A*          SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8000000   .75000000  .6375000         $0

4900720491  4841  ECHO SPRINGS #3-10 FED          CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000         $0

4900720492  4842  ECHO SPRINGS #3-14              CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000 $6,297,141
4900720461  4843  ECHO SPRINGS #3-18A FED         CARBON      WY  WAMSUTTER NE  1.0000000  .8400000  1.00000000  .8400000 $5,799,338

4900720493  4844  ECHO SPRINGS #3-22A FED         CARBON      WY  WAMSUTTER NE  1.0000000  .8350000  1.00000000  .8350000 $4,447,607

4903721233  4845  SIBERIA RIDGE #3-22 FED         SWEETWATER  WY  WAMSUTTER NE  0.6000000  .4950000   .75000000  .6187500   $193,241

4903721358  4846  SIBERIA RIDGE #3-24A FED*       SWEETWATER  WY  WAMSUTTER NE  0.6743540  .5320905   .67435420  .5320905    $35,966

4900720462  4848  ECHO SPRINGS #3-24 FED          CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000 $6,795,550

4903721326  4851  ECHO SPRINGS #3-36X             SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8450000  1.00000000  .8450000 $2,254,866
4903722060  4852  ECHO SPRINGS #3-28 FED          SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8450000  1.00000000  .8450000   $850,150

4900721523  4856  ECHO SPRINGS #2-22A FED*        CARBON      WY  WAMSUTTER NE  1.0000000  .8350000  1.00000000  .8350000 $3,745,328

4903722998  4857  ECHO SPRINGS #2-36 STATE*       SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8450000  1.00000000  .8450000 $1,520,294

4900721255  4858  ECHO SPRINGS #2-14 FED*         CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000 $2,704,304

4900721256  4859  ECHO SPRINGS #2-10 FED*         CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000   $733,662

4903723067  5090  SIBERIA RIDGE #2-34 FED*        SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8750000  1.00000000  .8750000 $1,559,330

4903722935  5152  ECHO SPRINGS #6-2 FED*          SWEETWATER  WY  WAMSUTTER NE  0.0000000  .0337500  0.07500000  .0633750    $36,182

4903723127  5172  UPRC #3-27*                     SWEETWATER  WY  WAMSUTTER NE  1.0000000  .7750000  0.60000000  .4800000 $1,121,942
4903723251  5752  SIBERIA RIDGE 4-34 FED          SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8750000  1.00000000  .8750000 $1,414,029

4903722559  5759  UPRC #2-27                      SWEETWATER  WY  WAMSUTTER NE  1.0000000  .8000000  0.60000000  .4800000   $396,556
4900721352  5812  ECHO SPRINGS #2-24 FED          CARBON      WY  WAMSUTTER NE  1.0000000  .8250000  1.00000000  .8250000 $2,165,159

4900721375  5850  ECHO SPRINGS #2-18A FED         CARBON      WY
4903723652  8617  SIERRA RIDGE #5-26 FED*         SWEETWATER  WY  WAMSUTTER NE  0.2500000  .1875000  0.25000000  .1875000   $235,483

4900720845  4735  OVERLAND  #43-6 FED*            CARBON      WY  CRESTON       0.0000000  .6250000  0.00000000  .6250000         $0
4900720768  4736  CRESTON  #1-18 FED*             CARBON      WY  CRESTON       0.0000000  .0318750  0.37500000  .3131250    $13,787
4900720769  4737  CRESTON  #1-8 FED*              CARBON      WY  CRESTON       0.0000000  .0318750  0.37500000  .3093750    $15,123
                  SIBERIA RIDGE,SECTION 14        SWEETWATER  WY  SIBERIA RIDGE                      0.37500000  .3093750   $224,892
                  SIBERIA RIDGE,SECTION 22,NE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.75000000  .6187500   $146,341
                  SIBERIA RIDGE,SECTION 22,NW/4   SWEETWATER  WY  SIBERIA RIDGE                      0.75000000  .6187500   $145,996
                  SIBERIA RIDGE,SECTION 22,SE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.75000000  .6187500   $153,429
                  SIBERIA RIDGE,SECTION 24,NE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.67435420  .5320905   $120,607
                  SIBERIA RIDGE,SECTION 24,SE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.67435420  .5320905   $140,010
                  SIBERIA RIDGE,SECTION 24,NW/4   SWEETWATER  WY  SIBERIA RIDGE                      0.67435420  .5320905   $120,607
                  SIBERIA RIDGE,SECTION 26,NE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.25000000  .2187500    $55,045
                  SIBERIA RIDGE,SECTION 26,SE/4   SWEETWATER  WY  SIBERIA RIDGE                      0.25000000  .2187500    $50,799
                  SIBERIA RIDGE,SECTION 26,SW/4   SWEETWATER  WY  SIBERIA RIDGE                      0.25000000  .2187500    $50,799
                  ECHO SPRINGS 3-2A               CARBON      WY  ECHO SPRINGS                       0.07500000  .0633750         $0
                  STANDARD DRAW 3-36A             CARBON      WY  STANDARD DRAW                      1.00000000  .8450000         $0
                                                                                                                         ===========
                                                                                                 TOTAL ALLOCATED VALUE $47,500,000
<FN>

*DALEN Resources Oil & Gas Co. (now Enserch Exploration,  Inc.) assigned to Tgas
Investments LL C. its right, title and interest in and to the oil and gas leases
described in Exhibit 'A',  insofar,  and only insofar,  as such leases cover the
right to produce from t he Mesaverde formation the wells identified above b y an
asterisk.  Enserch's  lack of record title in such leases,  insofar only as they
cover the right to produce such wells from the  Mesaverde  formation,  shall not
constitute a Defect under Section 7 of the Purchase and Sale  Agreement to which
this Exhibit is attached.
</FN>


                                      B-1


                                    EXHIBIT C

                           ASSIGNMENT AND BILL OF SALE


      ENSERCH EXPLORATION,  INC. ("Grantor"), for Ten Dollars and other good and
valuable  consideration  (the  receipt  and  sufficiency  of  which  are  hereby
acknowledged), hereby GRANTS, BARGAINS, SELLS, CONVEYS, ASSIGNS, TRANSFERS, SETS
OVER, and DELIVERS unto ABRAXAS PETROLEUM CORPORATION whose address is 500 North
Loop 1604 East, Suite 100, San Antonio,  Texas 78232,  (herein called "Grantee")
the following described properties, rights and interests.

            (a) All of Grantor's  right,  title, and interest in and to the oil,
      gas  and  mineral   leases   described   in  Exhibit  A  hereto  (and  any
      ratifications  and  amendments  to  such  leases,   whether  or  not  such
      ratifications  and  amendments  are  described  in  Exhibit  A) and all of
      Grantor's  right,  title and interest in and to the fee mineral  interests
      described in Exhibit A, if any; and

            (b) All  rights,  titles,  and  interests  of  Grantor in and to, or
      otherwise  derived  from,  all  presently  existing and valid oil, gas and
      mineral   unitization,    pooling,    and   communitization    agreements,
      declarations,  and orders (including, without limitation, all units formed
      under orders, rules,  regulations,  or other official acts of any federal,
      state, or other authority having jurisdiction,  and voluntary  unitization
      agreements,  designations  and  declarations)  relating to the  properties
      described  in  subsection  (a) to the  extent  such  rights,  titles,  and
      interests are attributable to the properties  described in subsection (a);
      and

            (c) All  rights,  titles,  and  interests  of  Grantor in and to all
      presently  existing  and  valid  production  sales  contracts,   operating
      agreements,  and other  agreements and contracts that relate to any of the
      properties  described  in  subsections  (a) and (b) , to the  extent  such
      rights, titles, and interests are attributable to the properties described
      in subsections (a) and (b); and

            (d) All crude oil,  natural  gas,  casinghead  gas,  drip  gasoline,
      natural gasoline,  petroleum, natural gas liquids,  condensate,  products,
      liquids and other  hydrocarbons  and other  minerals or materials of every
      kind and  description,  including  without  limitation,  "line  fill"  and
      inventory  below  the  pipeline  connection  in  tanks,  insofar  as  such
      hydrocarbons  may be produced from or are  attributable  to the properties
      described in subsections (a) and (b) after the effective date hereof; and.

            (e) All  rights,  titles,  and  interests  of  Setter  in and to all
      materials,  supplies,  machinery,   equipment,   improvements,  and  other
      personal property and fixtures  (including,  but not limited to, all wells
      listed on Exhibit B hereto, all wells, wellhead equipment,  pumping units,
      flowlines,  tanks,  buildings,  injection  facilities,  saltwater disposal
      facilities,   compression   facilities,   gathering  systems,   and  other
      equipment) located on the properties  described in subsections (a) and (b)
      and used in connection with the exploration,  development,  operation,  or
      maintenance thereof.

The properties and interests specified in subsections (a), (b), (c), (d) and (e)
are herein sometimes collectively called the "Properties."

      TO HAVE  AND TO HOLD the  Properties  unto  Grantee,  its  successors  and
assigns, forever.

      EXCEPT FOR A SPECIAL  WARRANTY  OF TITLE AS  HEREINAFTER  DESCRIBED,  THIS
ASSIGNMENT AND BILL OF SALE IS MADE WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY
KIND, ALL REPRESENTATIONS AND WARRANTIES BEING EXPRESSLY DISCLAIMED SPECIFICALLY
IN THIS CONNECTION,  BUT WITHOUT  LIMITING THE GENERALITY OF THE FOREGOING,  ALL
EQUIPMENT,  OTHER PERSONAL  PROPERTY,  AND FIXTURES SOLD AND CONVEYED TO GRANTEE
ARE SOLD AND CONVEYED ON AN "AS IS" AND "WHERE IS" BASIS, AND GRANTOR  EXPRESSLY
DISCLAIMS  ANY  AND ALL  SUCH  OTHER  REPRESENTATIONS  AND  WARRANTIES.  WITHOUT
LIMITATION OF THE FOREGOING,  THE PROPERTIES  SHALL BE CONVEYED  PURSUANT HERETO
WITHOUT ANY WARRANTY OR REPRESENTATION,  WHETHER EXPRESS, IMPLIED,  STATUTORY OR
OTHERWISE,  RELATING  TO  THE  CONDITION,   QUANTITY,  QUALITY,  FITNESS  FOR  A
PARTICULAR  PURPOSE,  CONFORMITY  TO THE  MODELS  OR  SAMPLES  OF  MATERIALS  OR
MERCHANTABILITY  OF ANY  EQUIPMENT  OR ITS FITNESS  FOR ANY PURPOSE  WITHOUT ANY
OTHER  EXPRESS,   IMPLIED,   STATUTORY  OR  OTHER  WARRANTY  OR   REPRESENTATION
WHATSOEVER.  GRANTEE SHALL HAVE INSPECTED,  OR WAIVED (AND UPON CLOSING SHALL BE
DEEMED TO HAVE WAIVED) ITS RIGHT TO INSPECT, THE PROPERTIES FOR ALL PURPOSES AND
SATISFIED ITSELF AS TO THEIR PHYSICAL AND ENVIRONMENTAL CONDITION,  BOTH SURFACE
AND SUBSURFACE,  INCLUDING BUT NOT LIMITED TO CONDITIONS SPECIFICALLY RELATED TO
THE  PRESENCE,  RELEASE OR  DISPOSAL  OF  HAZARDOUS  SUBSTANCES,  SOLID  WASTES,
ASBESTOS OR OTHER MANMADE FIBERS OR NATURALLY  OCCURRING  RADIOACTIVE  MATERIALS
("NORM") IN, ON OR UNDER THE PROPERTIES.  GRANTEE IS RELYING SOLELY UPON ITS OWN
INSPECTION OF THE PROPERTIES,  AND GRANTEE SHALL,  EXCEPT AS PROVIDED  OTHERWISE
HEREIN,  ACCEPT  ALL OF THE SAME IN THEIR  "AS IS,  WHERE  IS"  CONDITION.  ALSO
WITHOUT   LIMITATION   OF  THE   FOREGOING,   GRANTOR   MAKES  NO   WARRANTY  OR
REPRESENTATION,  EXPRESS, IMPLIED, STATUTORY OR OTHERWISE, AS TO THE ACCURACY OR
COMPLETENESS  OF  ANY  DATA,  REPORTS,  RECORDS,  PROJECTIONS,   INFORMATION  OR
MATERIALS NOW,  HERETOFORE OR HEREAFTER  FURNISHED OR MADE AVAILABLE TO BUYER IN
CONNECTION  WITH THIS  AGREEMENT  INCLUDING,  WITHOUT  LIMITATION,  RELATIVE  TO
PRICING  ASSUMPTIONS,  OR QUALITY OR QUANTITY OF  HYDROCARBON  RESERVES (IF ANY)
ATTRIBUTABLE  TO THE PROPERTIES OR THE ABILITY OR POTENTIAL OF THE PROPERTIES TO
PRODUCE  HYDROCARBONS  OR THE  ENVIRONMENTAL  CONDITION OF THE PROPERTIES OR ANY
OTHER MATTERS CONTAINED IN THE PROPRIETARY DATA OR ANY OTHER MATERIALS FURNISHED
OR MADE AVAILABLE TO BUYER BY GRANTOR OR BY GRANTOR'S AGENTS OR REPRESENTATIVES.
ANY AND ALL SUCH DATA,  RECORDS,  REPORTS,  PROJECTIONS,  INFORMATION  AND OTHER
MATERIALS  (WRITTEN OR ORAL) FURNISHED BY GRANTOR OR OTHERWISE MADE AVAILABLE OR
DISCLOSED  TO  GRANTEE  SHALL NOT  CREATE OR GIVE  RISE TO ANY  LIABILITY  OF OR
AGAINST  GRANTOR AND ANY  RELIANCE  ON OR USE OF THE SAME SHALL BE AT  GRANTEE'S
SOLE RISK TO THE MAXIMUM EXTENT PERMITTED BY LAW.

TO THE EXTENT OF  GRANTOR'S  INTEREST IN THE  PROPERTIES  AS SHOWN ON EXHIBIT B,
GRANTOR  WARRANTS  TITLE BY, THROUGH AND UNDER  GRANTOR,  BUT NOT OTHERWISE,  IT
BEING  EXPRESSLY  UNDERSTOOD  THAT THE TERM  "GRANTOR"  AS USED IN THIS  SPECIAL
WARRANTY  PROVISION  REFERS  TO  ENSERCH  EXPLORATION,   INC.  AND  NOT  TO  ITS
PREDECESSORS IN TITLE INCLUDING,  BUT NOT LIMITED TO, DALEN  CORPORATION,  DALEN
RESOURCES OM & GAS CO.,  PG&E  RESOURCES  COMPANY,  PG&E  ENTERPRISES  AND THEIR
PREDECESSORS.  THIS SPECIAL  WARRANTY  SHALL NOT COVER OR PERTAIN TO TITLE AS IT
MAY  BE  AFFECTED  BY  THAT  CERTAIN  ASSIGNMENT  OF OIL  AND  GAS  LEASES  WITH
RESERVATION  OF PRODUCTION  PAYMENT,  DATED  EFFECTIVE  AUGUST 1, 1995,  BETWEEN
GRANTOR AND TGAS INVESTMENTS L.L.C.

      This Assignment and Bill of Sale is subject to the terms and provisions of
that certain  Purchase and Sale Agreement,  dated May 22, 1996,  between Grantor
and Grantee.

      This  Assignment and Bill of Sale may be executed in several  counterparts
all of which are identical,  except that, to facilitate recordation,  in certain
counterparts  hereof  only that  portion  of  Exhibit A that  contains  specific
descriptions  of properties  located in the recording  jurisdiction in which the
particular  counterpart  is to be recorded are included,  and other  portions of
Exhibit A are included by reference only. All such  counterparts  together shall
constitute one and the same  instrument.  Complete copies of this Assignment and
Bill of Sale  containing  the entire Exhibit A have been retained by Grantor and
Grantee.






      IN WITNESS W]HEREOF this Assignment and Bill of Sale has been executed and
delivered on , effective  as to runs of oil and  deliveries  of gas, and for all
other  purposes,  as of 7:00  o'clock  a.m.  local time at the  locations of the
Properties, respectively, on April 1, 1996.



                              ENSERCH EXPLORATION, INC.

                              By:________________________
                              Name:______________________
                              Title:_____________________


                              ABRAXAS PETROLEUM CORPORATION

                              By:_________________________
                              Name:_______________________
                              Title:______________________





STATE OF TEXAS          ss.
                        ss.
COUNTY OF DALLAS  ss.

     On this _____ day of  ________,  before me, a Notary  Public of said state,
duly commissioned and sworn,  appeared , known to me to be the person whose name
is subscribed to the within instrument as of ENSERCH EXPLORATION,  INC., a Texas
corporation, and acknowledged to me that such corporation executed the same.

      Witness my hand and official seal.



                              _________________________________
                              Notary Public, State of Texas

My Commission Expires:

______________________


STATE OF TEXAS          ss.
                        ss.
COUNTY OF DALLAS  ss.

     On this _____ day  of_______  , before me, a Notary  Public of said  state,
duly commissioned and sworn,  appeared , known to me to be the person whose name
is subscribed to the within  instrument as of ABRAXAS PETROLEUM  CORPORATION,  a
Texas  corporation,  and acknowledged to me that such  corporation  executed the
same.

      Witness my hand and official seal.



                              ___________________________________
                              Notary Public, State of Texas

My Commission Expires:

__________________________












                                    EXHIBIT D

                               Disclosure Schedule


1.    Certain litigation: None

2.    Certain environmental matters:  None

                                      D-1