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                                                                    Exhibit 3.13

                              AMENDED AND RESTATED
                                     BYLAWS

                                       OF

                             SANDIA OIL & GAS CORP.

                                    ARTICLE I

                                     OFFICES

     Section 1. PRINCIPAL OFFICE. The principal office of the Corporation shall
be 909 N.E. Loop 410, Suite 818, San Antonio, Texas 78209, or such other place
as the Board of Directors may from time to time designate.

     Section 2. OTHER OFFICES. The Corporation may also have offices at such
other places both within and without the State of Texas as the Board of
Directors may from time to time determine or the business of the Corporation may
require.

                                   ARTICLE II

                                  SHAREHOLDERS

     Section 1. TIME AND PLACE OF MEETING. All meetings of the shareholders
shall be held at such time and at such place within or without the State of
Texas as shall be determined by the Board of Directors.

     Section 2. ANNUAL MEETINGS. The annual meetings of the shareholders shall
be held during the month of September each year, at such place within or without
the State of Texas, on such day, and at such time as the Board of Directors
shall determine by resolution and set forth in the notice of the meeting. At
such annual meeting, the shareholders shall elect directors and transact such
other business as may properly be brought before the meeting.

     Section 3. SPECIAL MEETINGS. Special meetings of the shareholders may be
called at any time by the Chairman of the Board, President or the Board of
Directors, and shall be called by the Chairman of the Board, President or
Secretary at the request in writing of the holders of not less than ten percent
(10%) of all the shares issued, outstanding and entitled to vote at the proposed
special meeting. Such request shall state the purpose or purposes of the
proposed meeting. Business transacted at special meetings shall be confined to
the purposes stated in the notice of the meeting.

     Section 4. NOTICE. Written or printed notice stating the place, day and
hour of any shareholders' meeting, and, in the case of a special meeting, the
purpose or purposes for which the meeting is called, shall be delivered not less
than ten (10) nor more than sixty (60) days before the date of the meeting,
either personally or by mail, by or at the direction of the

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President, Secretary, or the officer or person calling the meeting, to each
shareholder entitled to vote at such meeting. If mailed, such notice shall be
deemed to be delivered when deposited in the United States mail, postage
prepaid, to the shareholder at his address as it appears on the share transfer
records of the Company. Any notice required to be given to a shareholder
pursuant to this Section 4 or any other provision of these Bylaws, the Articles
of Incorporation of the Company or any provision of the Texas Business
Corporation Act (herein called the "Act") need not be given to such shareholder
if (a) notice of two (2) consecutive annual meetings of shareholders of the
Company, and all notices of meetings of shareholders of the Company held during
the period between such annual meetings, if any, or (b) all (but in no event
less than two (2)) payments (if sent by first class mail) of distributions or
interest on securities of the Company during any twelve-month period, have been
mailed to such shareholder at his address as shown on the share transfer records
of the Company and have been returned undeliverable, and any action or meeting
of shareholders of the Company taken or held without notice to such shareholder
shall have the same force and effect as if notice had been duly given to such
shareholder; provided, however, that if such shareholder delivers to the Company
a written notice setting forth his or her then current address, the requirement
that notice be given to such shareholder shall be reinstated.

     Section 5. RECORD DATE. The Board of Directors may fix in advance a record
date for the purpose of determining shareholders entitled to notice of or to
vote at a meeting of shareholders, such record date to be not less than ten (l0)
nor more than sixty (60) days prior to such meeting, or the Board of Directors
may close the stock transfer books for such purpose for a period of not less
than ten (10) nor more than sixty (60) days prior to such meeting. In the
absence of any action by the Board of Directors, the date upon which the notice
of the meeting is mailed shall be the record date.

     For purposes of determining the shareholders entitled to consent to
corporate action in writing without a meeting, the Board of Directors may fix a
record date, which record date shall not precede the date upon which the
resolution fixing the record date is adopted by the Board of Directors, and
which date shall not be more than ten (10) days after the date upon which the
resolution fixing the record date is adopted by the Board of Directors. If the
Board of Directors does not fix the record date, the record date for determining
shareholders entitled to consent to corporate action in writing without a
meeting, when no prior action by the Board of Directors is necessary, shall be
the first date on which a signed written consent setting forth the action taken
or proposed to be taken is delivered to the Company at its registered office in
the State of Texas or its principal place of business. If the Board of Directors
does not fix the record date, and prior action by the Board of Directors is
necessary, the record date for determining the shareholders entitled to consent
to corporate action in writing without a meeting shall be at the close of
business on the day on which the Board of Directors adopts the resolution taking
such prior action.

     Section 6. QUORUM. The holders of a majority of the issued and outstanding
shares entitled to vote thereat, present in person or represented by proxy,
shall constitute a quorum at all meetings of the shareholders for the
transaction of business except as otherwise provided by the Act or the Articles
of Incorporation. If, however, such quorum shall not be present or represented
at any meeting of the shareholders, the shareholders entitled to vote, present
in person or represented by proxy, shall have power to adjourn the meeting from
time to time,

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without notice other than announcement at the meeting, until a quorum shall be
present or represented. When any adjourned meeting is reconvened and a quorum
shall be present or represented, any business may be transacted which might have
been transacted at the meeting as originally notified. Once a quorum is
constituted, the shareholders present or represented by proxy at a meeting may
continue to transact business until adjournment, notwithstanding the subsequent
withdrawal therefrom of such number of shareholders as to leave less than a
quorum.

     Section 7. VOTING. When a quorum is present at any meeting, the vote of the
holders of a majority of the shares present or represented by proxy at such
meeting and entitled to vote shall be the act of the shareholders, unless the
vote of a different number is required by the Act, Articles of Incorporation or
any other provision of these Bylaws. When a quorum is present at any meeting at
which directors are to be elected, a plurality of votes cast by the holders of
all of the outstanding shares entitled to vote in the election of Directors
shall be sufficient to elect a director.

     Section 8. PROXY. Every proxy must be executed in writing by the
shareholder or by his duly authorized attorney-in-fact, and shall be filed with
the Secretary of the Company prior to or at the time of the meeting. A telegram,
telex, cablegram, or similar transmission by the shareholder, or a photographic,
photostatic, facsimile, or similar reproduction of a writing executed by the
shareholder or by his duly authorized attorney-in-fact, shall be treated as an
execution in writing for purposes of this Section 8. No proxy shall be valid
after eleven (11) months from the date of its execution unless otherwise
provided therein. Each proxy shall be revocable unless the proxy form
conspicuously states that the proxy is irrevocable and the proxy is coupled with
an interest. Proxies coupled with an interest include the appointment as proxy
of:

          (a)  a pledgee;

          (b)  a person who purchased or agreed to purchase, or owns or holds an
     option to purchase, the shares covered by such proxy;

          (c)  a creditor of the Company who extended credit to the Company
     under terms requiring appointment of the creditor as proxy;

          (d)  an employee of the Company whose employment contract requires
     appointment of the employee as proxy; and

          (e)  a party to a voting agreement entered into pursuant to and in
     compliance with applicable provisions of the Act.

     Section 9. ACTION BY WRITTEN CONSENT. Any action required or permitted to
be taken at any meeting of the shareholders may be taken without a meeting if a
consent in writing, setting forth the action so taken, shall be signed by the
holder or holders of shares having not less than the minimum number of votes
that would be necessary to take such action at a meeting at which the holders of
all shares entitled to vote on the action were present and voted, and such
consent shall have the same force and effect as a vote of shareholders. Every
written consent shall bear the date of signature of each shareholder who signs
the consent. No written consent shall be effective to take the action that is
the subject of the consent unless, within 60 days after the date of the earliest
dated consent delivered to the Company in the manner required by this Section 9,
a consent or consents signed by the holder or holders of shares having not less
than the minimum

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number of votes that would be necessary to take the action that is the subject
of the consent are delivered to the Company by delivery to its registered
office, its principal place of business, or an officer or agent of the Company
having custody of the books in which proceedings of meetings of shareholders are
recorded. Delivery may be by hand or certified or registered mail, return
receipt requested. Delivery to the Company's principal place of business shall
be addressed to the president or principal executive officer of the Company. A
telegram, telex, cablegram, or similar transmission by a shareholder, or a
photographic, photostatic, facsimile, or similar reproduction of a writing
signed by a shareholder, shall be regarded as signed by the shareholder for
purposes of this Section. Prompt notice of the taking of any action by
shareholders without a meeting by less than unanimous written consent shall be
given to those shareholders who did not consent in writing to the action

     Section 10. MEETINGS BY CONFERENCE TELEPHONE. Shareholders may participate
in and hold meetings of the shareholders by means of conference telephone or
similar communications equipment by means of which all persons participating in
the meeting can hear each other, and participation in such a meeting shall
constitute presence in person at such meeting, except where a person
participates in the meeting for the express purpose of objecting to the
transactions of any business on the ground that the meeting is not lawfully
called or convened.

                                   ARTICLE III

                                    DIRECTORS

     Section 1. NUMBER OF DIRECTORS. The number of directors of the Company
shall be no less than one (1) nor more than five (5), as may be determined by
resolution adopted by the directors at the annual meeting, but no decrease shall
have the effect of reducing the term of any incumbent director. Directors shall
be elected at the annual meeting of the shareholders, except as provided in
Section 2, and each director shall hold office until such director's successor
is elected and qualified, or until such director's earlier death, resignation or
removal. Directors need not be shareholders of the Company or residents of the
State of Texas.

     Section 2. VACANCIES; REMOVAL. Any vacancy occurring in the Board of
Directors may be filled by the affirmative vote of a majority of the remaining
directors though the remaining directors may constitute less than a quorum of
the Board of Directors as fixed by Section 8 of this Article. A director elected
to fill a vacancy shall be elected for the unexpired term of such director's
predecessor in office. Any directorship to be filled by reason of an increase in
the number of directors may be filled only by election by the shareholders at an
annual meeting or at a special meeting of shareholders called for that purpose.
At any annual meeting of shareholders, or any special meeting called for such
purpose, any director may be removed from office, for or without cause, even
though his term may not have expired, by the affirmative vote of a majority in
number of shares of the shareholders present.

     Section 3. GENERAL POWERS; VOTING. Except for circumstances in which the
approval of the shareholders is required by the Act, the Articles of
Incorporation, these Bylaws or by other non-waivable provisions of applicable
law, the powers of the Company shall be exercised by or under the authority of,
and the business and affairs of the Company shall be managed under the

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direction of, the Board of Directors. In furtherance thereof, the Board of
Directors shall have exclusive duty, power and authority to manage, control and
make all decisions and give (or withhold) all consents or approvals with respect
to the business, operations, investments and affairs of the Company and its
properties and to do all things which, in the judgment of the Board of
Directors, are necessary, proper or desirable to carry out and exercise the
foregoing authority. The vote of a majority of the directors at a meeting at
which a quorum is present shall be the act of the Board of Directors.

     Section 4. PLACE OF MEETINGS. Meetings of the Board of Directors, both
regular and special, may be held either within or without the State of Texas, as
determined by the Board of Directors.

     Section 5. ANNUAL MEETINGS. The first meeting of each newly elected Board
of Directors shall be held without further notice immediately following the
annual meeting of the shareholders, and at the same place, unless by unanimous
consent of the directors then elected and serving such time or place shall be
changed.

     Section 6. REGULAR MEETINGS. Regular meetings of the Board of Directors may
be held without notice at such time and place as shall from time to time be
determined by the Board of Directors.

     Section 7. SPECIAL MEETINGS. Special meetings of the Board of Directors may
be called by the Chairman of the Board or the President on two days' notice to
each director, either personally or by mail or by telegram. Special meetings
shall be called by the Chairman of the Board, the President or Secretary in like
manner and on like notice on the written request of any two (2) directors.

     Section 8. QUORUM. At all meetings of the Board of Directors the presence
of a majority of the number of directors fixed by Section 1 of this Article
shall be necessary and sufficient to constitute a quorum for the transaction of
business. If a quorum shall not be present at any meeting of directors, the
directors present thereat may adjourn the meeting from time to time without
notice other than announcement at the meeting, until a quorum shall be present.

     Section 9. COMMITTEES. The Board of Directors may designate committees
consisting of one (1) or more directors, which committees shall have such
authority and shall perform such functions as may be provided in such
resolution. Such committee or committees shall have such name or names as may be
designated by the Board of Directors and shall keep regular minutes of their
proceedings and report the same to the Board of Directors when required.

     Section 10. EXECUTIVE COMMITTEE. The Board of Directors may appoint an
Executive Committee with such members and powers as the Board shall determine by
written resolution. Members of the Executive Committee need not be shareholders
or directors of the Company.

     Section 11. COMPENSATION OF DIRECTORS. Directors, as such, shall not
receive any stated salary for their services, but, by resolution of the Board of
Directors, a fixed sum and expenses of attendance, if any, may be allowed for
attendance at each regular or special meeting of the Board of Directors;
provided that nothing herein contained shall be construed to preclude any
directors

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from serving the Company in any other capacity and receiving compensation
therefor.

     Section 12. ACTION BY WRITTEN CONSENT. Any action required or permitted to
be taken at any meeting of the Board of Directors or of any committee designated
by the Board of Directors may be taken without a meeting if a written consent,
setting forth the action so taken, is signed by all the members of the Board of
Directors or of such committee, and such consent shall have the same force and
effect as a unanimous vote at a meeting.

     Section 13. MEETINGS BY CONFERENCE TELEPHONE. Members of the Board of
Directors or of any committee designated by the Board of Directors may
participate in and hold a meeting of the Board of Directors or committee by
means of conference telephone or similar communications equipment by means of
which all persons participating in the meeting can hear each other, and
participation in such a meeting shall constitute presence in person at such
meeting, except where a person participates in the meeting for the express
purpose of objecting to the transactions of any business on the ground that the
meeting is not lawfully called or convened.

     Section 14. RESIGNATIONS. Each director shall have the right to resign at
any time upon written notice of such resignation to the President or Secretary
of the Company. Unless otherwise specified in such written notice, the
resignation shall take effect upon the receipt thereof, and acceptance of such
resignation shall not be necessary to make same effective. Filling the vacancy
left by a resigning director shall be filled pursuant to Section 2 of this
Article.

     Section 15. INTERESTED DIRECTORS. No contract or transaction between the
Company and one or more of its directors or officers, or between the Company and
any other corporation, partnership, association or other organization in which
one or more of its directors or officers are directors or officers or have a
financial interest, shall be void or voidable solely for this reason, solely
because the director or officer is present at or participates in the meeting of
the Board of Directors or committee thereof that authorizes the contract or
transaction, or solely because such director's or directors' votes are counted
for such purpose, if:

          (a)  The material facts as to his relationship or interest and as to
the contract or transaction are disclosed or are known to the Board of Directors
or the committee, and the Board of Directors or committee in good faith
authorizes the contract or transaction by the affirmative vote of a majority of
the disinterested directors, even though the disinterested directors be less
than a quorum; or

          (b)  The material facts as to such director's relationship or interest
and as to the contract or transaction are disclosed or are known to the
shareholders entitled to vote thereon, and the contract or transaction is
specifically approved in good faith by vote of the shareholders; or

          (c)  The contract or transaction is fair as to the Company as of the
time it is authorized, approved or ratified by the Board of Directors, a
committee thereof or the shareholders.

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     Common or interested directors may be counted in determining the presence
of a quorum at a meeting of the Board of Directors or of a committee that
authorizes the contract or transaction.

                                   ARTICLE IV

                                     NOTICES

     Section 1. FORM OF NOTICE. Whenever under the provisions of the Act, the
Articles of Incorporation or these Bylaws, notice is required to be given to any
shareholder or director, and no provision is made as to how such notice shall be
given, it shall not be construed to mean personal notice, but any such notice
may be given in writing, by mail, postage prepaid, addressed to such director or
shareholder at such address as appears on the books of the Company. Any notice
required or permitted to be given by mail shall be deemed to be given at the
time when the same be thus deposited, postage prepaid, in the United States mail
as aforesaid.

     Section 2. WAIVER. Whenever any notice is required to be given to any
shareholder or director of the Company under the provisions of the Act, the
Articles of Incorporation or these Bylaws, a waiver thereof in writing signed by
the person or persons entitled to such notice, whether before or after the time
stated in such notice, shall be deemed equivalent to the giving of such notice.

     Section 3. ATTENDANCE AS WAIVER. Attendance of a director at a meeting of
the Board of Directors or a committee thereof shall constitute a waiver of
notice of such meeting, except when a director attends a meeting for the express
purpose of objection to the transaction of any business on the ground that the
meeting is not lawfully called or convened.

                                    ARTICLE V

                                    OFFICERS

     Section 1. IN GENERAL. The officers of the Company shall be elected by the
Board of Directors and shall include a President and a Secretary. The Board of
Directors may also, if it chooses to do so, elect a Chairman of the Board, one
or more Vice Presidents, one or more Assistant Secretaries, a Treasurer and one
or more Assistant Treasurers, all of whom shall also be officers. Two or more
offices may be held by the same person.

     Section 2. ELECTION. The Board of Directors at its first meeting after each
annual meeting of the shareholders shall elect a President, a Vice President, a
Secretary and a Treasurer and may elect such other officers and agents as it
shall deem necessary and may determine the salaries of all officers and agents
from time to time. Each officer shall hold office until his or her successor is
elected and qualified, or until such officer's earlier death, resignation or
removal. Subject to any contractual rights of an officer, any officer elected or
appointed by the Board of Directors may be removed, for or without cause, at any
time by a majority vote of the full Board of

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Directors. Subject to any contractual rights of the Company, any officer may
resign at any time upon giving written notice to the Company. Election or
appointment of an officer or agent shall not of itself create a contractual
right of employment for such officer. Unless otherwise specified by the Board of
Directors at the time of election or appointment, or in an employment contract
approved by the Board of Directors, each officer's and agent's term shall end at
the first meeting of directors after the next annual meeting of shareholders.
Any two or more offices may be held by the same person.

     Section 3. CHAIRMAN. The Chairman of the Board of Directors shall be a
member of the Board of Directors and shall preside at all meetings of the
shareholders and the Board of Directors and shall have such other powers as may
from time to time be assigned by the Board of Directors.

     Section 4. PRESIDENT. The President shall be the chief executive officer of
the Company, shall preside at all meetings of the shareholders and the Board of
Directors in the absence of the Chairman of the Board, and shall have the
general and active management of the business of the Company and shall see that
all orders and resolutions of the Board of Directors are carried into effect.
Subject to any prior approval of the Board of Directors that may be required,
the President shall have the authority to execute all contracts, mortgages,
conveyances or other legal instruments in the name of and on behalf of the
Company, but this provision shall not prohibit the delegation of such powers by
the Board of Directors to some other officer, agent or attorney-in-fact of the
Company.

     Section 5. VICE PRESIDENTS. The Vice President or, if there be more than
one, the Vice Presidents in the order of their seniority or in any other order
determined by the Board of Directors, shall, in the absence or disability of the
President, perform the duties and exercise the powers of the President, and
shall generally assist the President and perform such other duties as the Board
of Directors shall prescribe.

     Section 6. SECRETARY. The Secretary shall attend all sessions of the Board
of Directors and all meetings of the shareholders and record all votes and the
minutes of all proceedings in a book to be kept for that purpose, and shall
perform like duties for any other committees of the Board of Directors when
required. The Secretary shall give, or cause to be given, notice of all meetings
of the shareholders and special meetings of the Board of Directors, and shall
perform such other duties as may be prescribed by the Board of Directors or
President, under whose supervision the Secretary shall carry out such duties.
The Secretary shall keep in safe custody the seal of the Company.

     Section 7. ASSISTANT SECRETARIES. Any Assistant Secretary shall, in the
absence or disability of the Secretary, perform the duties and exercise the
powers of the Secretary and shall perform such other duties as may be prescribed
by the Board of Directors or the President.

     Section 8. TREASURER. The Treasurer shall have the custody of all corporate
funds and securities, and shall keep full and accurate accounts of receipts and
disbursements of the Company, and shall deposit all moneys and other valuable
effects in the name and to the credit of the Company in such depositories as may
be designated by the Board of Directors. The Treasurer shall disburse the funds
of the Company as may be ordered by the Board of Directors,

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taking proper vouchers for such disbursements, and shall render to the President
and directors, at the regular meetings of the Board of Directors or whenever
they may require it, an account of all such transactions as Treasurer and of the
financial condition of the Company, and shall perform such other duties as may
be prescribed by the Board of Directors or the President.

     Section 9. ASSISTANT TREASURERS. Any Assistant Treasurer shall, in the
absence or disability of the Treasurer, perform the duties and exercise the
powers of the Treasurer and shall perform such other duties as may be prescribed
by the Board of Directors or the President.

                                   ARTICLE VI

                        CERTIFICATES REPRESENTING SHARES

     Section 1. FORM OF CERTIFICATES. The Company shall be authorized to deliver
certificates representing all shares to which shareholders are entitled.
Certificates representing shares of the Company shall be in such form as shall
be determined by the Board of Directors and shall be numbered consecutively and
entered in the books of the Company as they are issued. Each certificate shall
state upon the face thereof the holder's name, the number, class of shares, and
the par value of the shares or a statement that the shares are without par
value. They shall be signed by the President or a Vice President and the
Secretary or an Assistant Secretary, and may be sealed with the seal of the
Company or a facsimile thereof if the Company shall then have a seal. If any
certificate is countersigned by a transfer agent or registered by a registrar,
either of which is other than the Company or an employee of the Company, the
signatures of the Company's officers may be facsimiles. In case any officer or
officers who have signed, or whose facsimile signature or signatures have been
used on such certificate or certificates, shall cease to be such officer or
officers of the Company, whether because of death, resignation or otherwise,
before such certificate or certificates have been delivered by the Company or
its agents, such certificate or certificates may nevertheless be adopted by the
Company and be issued and delivered as though the person or persons who signed
the certificate or certificates or whose facsimile signature or signatures have
been used thereon had not ceased to be such officer or officers of the Company.

     Section 2. RESTRICTION ON TRANSFER OF SHARES. If any restriction on the
transfer, or registration of the transfer, of shares shall be imposed or agreed
to by the Company, as permitted by law, the Articles of Incorporation and these
Bylaws, such restriction shall be noted conspicuously on each certificate
representing shares in accordance with applicable law.

     Section 3. VOTING AGREEMENTS. A written counterpart of any voting agreement
entered into among any number of shareholders of the Company, or any number of
shareholders of the Company and the Company itself, for the purpose of providing
that shares of the Company shall be voted in the manner prescribed in the
agreement shall be deposited with the Company at its principal place of business
or registered office and shall be subject to the same right of examination by a
shareholder of the Company, in person or by agent or attorney, as are the books
and records of the Company. The existence of the agreement shall be noted
conspicuously on the certificate representing the shares that are subject to the
agreement.

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     Section 4. LOST CERTIFICATES. The Board of Directors may direct that a new
certificate be issued in place of any certificate theretofore issued by the
Company alleged to have been lost or destroyed, upon the making of an affidavit
of that fact by the person claiming the certificate to be lost or destroyed.
When authorizing the issue of a new certificate, the Board of Directors, in its
discretion and as a condition precedent to the issuance thereof, may require the
owner of the lost or destroyed certificate, or such owner's legal
representative, to advertise the same in such manner as it shall require and/or
give the Company a bond in such form, in such sum, and with such surety or
sureties as it may direct as indemnity against any claim that may be made
against the Company with respect to the certificate alleged to have been lost or
destroyed and may impose any other reasonable requirement.

     Section 5. TRANSFER OF SHARES. Shares of stock shall be transferable only
on the books of the Company by the holder thereof in person or by such holder's
duly authorized attorney and, upon surrender to the Company or to the transfer
agent of the Company of a certificate representing shares duly endorsed or
accompanied by proper evidence of succession, assignment or authority to
transfer, it shall be the duty of the Company or the transfer agent of the
Company to issue a new certificate to the person entitled thereto, cancel the
old certificate and record the transaction upon its books.

     Section 6. REGISTERED SHAREHOLDERS. The Company shall be entitled to
recognize the holder of record of any share or shares of stock as the holder in
fact thereof and, accordingly, shall not be bound to recognize any equitable or
other claim to or interest in such share or shares on the part of any other
person, whether or not it shall have express or other notice thereof, except as
otherwise provided by law.

                                   ARTICLE VII

                               GENERAL PROVISIONS

     Section 1. DIVIDENDS. Dividends upon the outstanding shares of the Company,
subject to the provisions of the Act and of the Articles of Incorporation, if
any, may be declared by the Board of Directors at any regular or special
meeting. Dividends may be declared and paid in cash, in property or in shares of
the Company, or any combination thereof, provided that all such declarations and
payments of dividends shall be in strict compliance with all applicable laws and
the Articles of Incorporation. The Board of Directors may fix in advance a
record date for the purposes of determining shareholders entitled to receive
payment of any dividend, such record date to be not more than sixty (60) days
prior to the payment date of such dividend, or the Board of Directors may close
the stock transfer books for such purpose for a period of not more than sixty
(60) days prior to the payment date of such dividend. In the absence of any
action by the Board of Directors, the date upon which the Board of Directors
adopts the resolution declaring such dividend shall be the record date.

     Section 2. FISCAL YEAR. The fiscal year of the Company shall be the
twelve-month period ending December 3l each year unless otherwise determined and
fixed by resolution of the Board of Directors.

     Section 3. SEAL. The Company may have a seal and said seal may be used by
causing it

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or a facsimile thereof to be impressed or affixed or in any manner reproduced.
Any officer of the Company shall have authority to affix the seal to any
document requiring it.

     Section 4. FACSIMILE SIGNATURES. In addition to the provisions for the use
of facsimile signatures elsewhere specifically authorized in these Bylaws,
facsimile signatures of any officer or officers of the Company may be used
whenever and as authorized by the Board of Directors.

     Section 5. RELIANCE UPON BOOKS, REPORTS AND RECORDS. A member of the Board
of Directors, or a member of any committee designated by the Board of Directors,
shall, in the performance of such person's duties, be protected to the fullest
extent permitted by law in relying upon the records of the Company and upon
information, opinion, reports or statements presented to the Company.

     Section 6. APPLICATION OF BYLAWS. In the event that any provisions of these
Bylaws is or may be in conflict with any law of the United States, of the State
of Texas or of any other governmental body or power having jurisdiction over
this Company, or over the subject matter to which such provision of these Bylaws
applies, or may apply, such provision of these Bylaws shall be inoperative to
the extent only that the operation thereof unavoidably conflicts with such law,
and shall in all other respects by in full force and effect.

                                  ARTICLE VIII

                                    INDEMNITY

     Section 1. INDEMNIFICATION OF DIRECTORS AND OFFICERS. The Company shall
indemnify, to the fullest extent permitted by, and in the manner permissible
under, the laws of the State of Texas, any person made, or threatened to be
made, a party to an action, suit or proceeding, whether criminal, civil,
administrative or investigative, by reason of the fact that he is or was a
director, advisory director or officer of the Company, or served another
Company, partnership, joint venture, trust or other enterprise as a director,
advisory director, officer, employee or agent at the request of the Company,
against expenses (including attorneys' fees), judgments, fines and amounts paid
in settlement actually and reasonably incurred by such person in connection with
such action, suit or proceeding. The Board of Directors in its discretion shall
have the power on behalf of the Company to indemnify similarly any person, other
than a director, advisory director or officer, made a party to any action, suit
or proceeding by reason of the fact that he is or was an employee or agent of
the Company. The provisions of this Article VIII shall be applicable to persons
who have ceased to be directors, advisory directors, officers, employees or
agents of the Company and shall inure to the benefit of their heirs, executors
and administrators.

     Section 2. INDEMNIFICATION OF EMPLOYEES AND AGENTS. The Company may, to the
extent authorized from time to time by the Board of Directors, provide rights to
indemnification and to the advancement of expenses to employees and agents of
the Company similar to those conferred in Section 1 of this Article VIII to
directors officers of the Company.

     Section 3. INDEMNIFICATION NOT EXCLUSIVE. The rights of indemnification and
reimbursement provided for in Section 1 of this Article shall not be deemed
exclusive of any

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other rights to which such director or officer may be entitled under the
Articles of Incorporation, any bylaws, agreement, vote of shareholders, or as a
matter of law or otherwise.

                                   ARTICLE IX

                                     BYLAWS

     Section 1. AMENDMENTS. These Bylaws may be altered, amended or repealed and
new Bylaws may be adopted by the Board of Directors at any regular meeting or at
any special meeting called for that purpose.

     Section 2. WHEN BYLAWS SILENT. It is expressly recognized that when the
Bylaws are silent as to the manner of performing any corporate function, the
provisions of the Act shall control.

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                            CERTIFICATE OF SECRETARY

     The undersigned does hereby certify that (i) he or she is the duly elected
and qualified Secretary of Sandia Oil & Gas Corp., a Texas corporation (the
"Company"), and (ii) the foregoing is a true and correct copy of the Amended and
Restated Bylaws of the Company reviewed and adopted by the Board of Directors of
the Company on January 20, 2003.

                                         /s/    Chris E. Williford
                                                ------------------
                                                Secretary

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