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                                                                   EXHIBIT 10.12

                             TERMINATION AGREEMENT

         THIS TERMINATION AGREEMENT (this "Agreement"), dated as of May 22,
1998, is made and entered into by and among Vista Energy Resources, Inc., a
Delaware corporation ("Newco"), Midland Resources, Inc., a Texas corporation
(the "Company"), and Marilyn D. Wade (the "Executive").

                              W I T N E S S E T H:

         WHEREAS, concurrently herewith, Newco, Midland Merger Co. (the "Sub"),
Vista Resources Partners, L.P. and the Company are entering into an Agreement
and Plan of Merger (as such agreement may hereafter be amended from time to
time, the "Merger Agreement"; capitalized terms used and not otherwise defined
herein have the respective meanings ascribed to them in the Merger Agreement),
pursuant to which Sub will be merged with and into the Company (the "Merger");
and

         WHEREAS, as an inducement and a condition to entering into the Merger
Agreement, Newco has required that Executive agree, and Executive has agreed,
to enter into this Agreement.

         NOW, THEREFORE, in consideration of the foregoing and the
representations, warranties, covenants and agreements contained herein, the
parties hereto, intending to be legally bound, hereby agree as follows:

         1.      EMPLOYMENT AGREEMENT.  Executive hereby represents and
warrants that his employment relationship with the Company is pursuant to and
governed by the Employment Agreement dated as of March 30, 1998, by and between
the Company and the Executive, a true and correct copy of which is attached
hereto as Annex I (the "Employment Agreement").

         2.      TERMINATION OF EMPLOYMENT AGREEMENT.  Effective as of the
Effective Time (a) Executive hereby tenders his resignation as an officer and
director of the Company and each of its subsidiaries, and (b) the Employment
Agreement shall be terminated in full without any further action on the part of
the Company or Executive.  Except as expressly provided in this Agreement, from
and after the date of termination of the Employment Agreement, Executive shall
not be entitled to receive any further wages, compensation, stock options, or
benefits arising pursuant to the Employment Agreement or his employment
relationship with the Company or any of its subsidiaries and Executive shall
not be entitled to any post termination wages, compensation or benefits
(including, without limitation, severance pay, vacation pay or sick pay).  As
consideration for the termination of the Employment Agreement, the Company
hereby agrees to pay Executive immediately after the Effective Time, by means
of wire transfer of immediately available funds, an amount equal to $56,590.16.
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         3.      RELEASE OF CLAIMS.

                 (a)      RELEASE BY EXECUTIVE.  Effective as of the Effective
Time, Executive hereby releases and discharges the Released Parties from all
Claims and Damages, including those related to, arising from, or attributed to
(i) his employment with[, and membership on the Boards of Directors for, the
Company and its subsidiaries and resignations therefrom, (ii) the Employment
Agreement, and (iii) all other acts or omissions related to any matter at any
time prior to and including the date of termination of the Employment
Agreement; except that this release shall not include Executive's (A)
entitlement to continued group medical coverage in accordance with the
Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA"), (B) vested
account balances in the employee benefit plans described in Annex II attached
hereto, (C) rights of Executive arising under this Agreement or the Merger
Agreement, or (D) rights to indemnification under the Articles of Incorporation
and Bylaws of the Company.  Executive understands and expressly agrees that,
unless specifically excluded from this release, this release extends to all
Claims and Damages of every nature and kind, known or unknown, suspected or
unsuspected, past or present, whether or not these Claims and Damages were set
forth in any writing, and that all such Claims and Damages are hereby expressly
settled or waived.

                 (b)      DEFINITIONS.  As used in this Section 3, the
following terms shall have meanings set forth below:

                          (i)     "Claims" means all theories of recovery of
         whatever nature, whether known or unknown, and now recognized by the
         law or equity of any jurisdiction, based on acts, omissions or other
         matters occurring on or before the date the parties sign this
         Agreement.  This term includes, without limitation, lawsuits,
         petitions, complaints, causes of action, charges, indebtedness,
         losses, claims, liabilities, and demands, whether arising in equity or
         under the common law or under any contract (including, without
         limitation, the Employment Agreement), statute, regulation or
         ordinance.  This term also includes, without limitation, any Claim of
         discrimination (based on age or any other factor) under any statute or
         law (including, without limitation, the Age Discrimination in
         Employment Act, 29 U.S.C. Section  621, et seq.; Title VII of the
         Civil Rights Act of 1964, 42 U.S.C. Section  2000e, et seq.; and the
         Americans with Disabilities Act, 42 U.S.C.  Section  12101, et seq.),
         and all Claims asserted by Executive, in writing or otherwise, or
         which could be asserted, by Executive.

                          (ii)    "Damages" means all elements of relief or
         recovery of whatever nature, whether known or unknown, which are
         recognized by the law or equity of any jurisdiction.  This term
         includes, without limitation, actual, incidental, indirect,
         consequential, compensatory, liquidated, exemplary, and punitive
         damages; rescission, attorneys' fees; interest; costs; equitable
         relief; and expenses.

                          (iii)   "Released Parties" means and includes the
         Company and its subsidiaries, and all of the foregoing entities' past,
         present and future shareholders, directors, officers, employees,
         agents, insurance carriers, employee benefit plans (and such plans'
         fiduciaries, trustees, administrators and representatives),
         predecessors, successors, assigns, executors, administrators,
         attorneys and representatives, in both their corporate and individual
         capacities.


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         4.      SALARY.  Executive shall be paid the pro rata portion of her
annual base salary of $50,000, less lawful taxes and withholdings, to and
through the date of termination of the Employment Agreement in accordance with
the Company's customary payroll practices.

         5.      CONFIDENTIALITY.

                 (a)      PROTECTION OF CONFIDENTIAL INFORMATION AND TRADE
SECRETS.  Executive acknowledges that the business of the Company and its
subsidiaries is highly competitive and that their contracts, books, records,
and documents, their technical information concerning their services, pricing
techniques, and computer system and software, and the names of and other
information (such as credit and financial data) concerning their customers and
business affiliates, all comprise confidential business information and trade
secrets which are valuable, special, and unique assets which the Company and
its subsidiaries use in their business to obtain a competitive advantage over
their competitors.  (All such information belonging to the Company and its
subsidiaries is jointly referred to herein as "Confidential Information and
Trade Secrets.")  Effective as of the Effective Time, Executive agrees that all
Confidential Information and Trade Secrets are the exclusive, confidential, and
proprietary information and property of the Company and, except as necessary to
perform the consulting services to be provided hereunder, will not be used by
Executive for any other purpose or in any other manner.  Executive further
acknowledges that protection of such Confidential Information and Trade Secrets
against unauthorized disclosure and use is of critical importance to the
Company and its subsidiaries in maintaining their competitive position.
Executive hereby agrees that he will not make any unauthorized disclosure of
any such Confidential Information and Trade Secrets, or make any unauthorized
use thereof.  In the event that Executive is requested pursuant to, or required
by, applicable law or regulation or by legal process to disclose any
Confidential Information and Trade Secrets, Executive agrees to provide the
Company with prompt notice of such request(s) to enable the Company to seek an
appropriate protective order; provided, however, that Executive shall not be
prohibited from complying with any such request unless an appropriate
protective order is in place.

         (b)     SCOPE OF PROHIBITED ACTIVITIES; REMEDIES.  Executive
acknowledges that the scope of prohibited activities, and time of duration of
the provisions of this Section 5 are reasonable and are no broader than are
necessary to protect the goodwill and legitimate business interests of the
Company and its subsidiaries.  Executive also acknowledges that the provisions
of this Section 5 do not and will not impose any unreasonable burden on
Executive.  Executive further acknowledges that a violation of this Section 5
will cause irreparable damage to the Company and its subsidiaries, entitling
them to an injunction and other equitable relief in a court of competent
jurisdiction against Executive.  In addition, the Company and its subsidiaries
shall be entitled to whatever other remedies they may have at law, including,
without limitation, reasonable attorneys fees and costs incurred by the Company
and its subsidiaries in enforcing the terms of this Section 5.

         6.      MISCELLANEOUS.

                 (a)      ENTIRE AGREEMENT.  This Agreement constitutes the
entire agreement between the parties with respect to the subject matter hereof
and supersedes all other prior agreements and understandings, both written and
oral, between the parties with respect to the subject matter hereof.





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                 (b)      CERTAIN EVENTS.  Executive agrees that this Agreement
and the obligations hereunder shall be binding upon his heirs, guardians,
administrators or successors.

                 (c)      ASSIGNMENT.  This Agreement shall not be assigned by
operation of law or otherwise without the prior written consent of the other
party.

                 (d)      AMENDMENTS, WAIVERS, ETC.  This Agreement may not be
amended, changed, supplemented, waived or otherwise modified or terminated,
except upon the execution and delivery of a written agreement executed by the
parties hereto.

                 (e)      NOTICES.  All notices, requests, claims, demands and
other communications hereunder shall be in writing and shall be given (and
shall be deemed to have been duly received if so given) by hand delivery,
telegram, telex or telecopy, or by mail (registered or certified mail, postage
prepaid, return receipt requested) or by any courier service, such as Federal
Express, providing proof of delivery.  All communications hereunder shall be
delivered to the respective parties at the addresses provided on the signature
pages hereto.

                 (f)      SEVERABILITY.  Whenever possible, each provision or
portion of any provision of this Agreement will be interpreted in such manner
as to be effective and valid under applicable law but if any provision or
portion of any provision of this Agreement is held to be invalid, illegal or
unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect
any other provision or portion of any provision in such jurisdiction, and this
Agreement will be reformed, construed and enforced in such jurisdiction as if
such invalid, illegal or unenforceable provision or portion of any provision
had never been contained herein.

                 (g)      SPECIFIC PERFORMANCE.  Each of the parties hereto
recognizes and acknowledges that a breach by it of any covenants or agreements
contained in this Agreement will cause the other party to sustain damages for
which it would not have an adequate remedy at law for money damages, and
therefore each of the parties hereto agrees that in the event of any such
breach the aggrieved party shall be entitled to the remedy of specific
performance of such covenants and agreements and injunctive and other equitable
relief in addition to any other remedy to which it may be entitled, at law or
in equity.

                 (h)      REMEDIES CUMULATIVE.  All rights, powers and remedies
provided under this Agreement or otherwise available in respect hereof at law
or in equity shall be cumulative and not alternative, and the exercise of any
thereof by any party shall not preclude the simultaneous or later exercise of
any other such right, power or remedy by such party.

                 (i)      NO WAIVER.  The failure of any party hereto to
exercise any right, power or remedy provided under this Agreement or otherwise
available in respect hereof at law or in equity, or to insist upon compliance
by any other party hereto with its obligations hereunder, and any custom or
practice of the parties at variance with the terms hereof, shall not constitute
a waiver by such party of its right to exercise any such or other right, power
or remedy or to demand such compliance.





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                 (j)      NO THIRD PARTY BENEFICIARIES.  This Agreement is not
intended to be for the benefit of, and shall not be enforceable by, any person
or entity who or which is not a party hereto.

                 (k)      GOVERNING LAW.  This Agreement shall be governed and
construed in accordance with the laws of the State of Texas, without giving
effect to the principles of conflicts of law thereof.

                 (l)      JURISDICTION.  Each party hereby irrevocably submits
to the exclusive jurisdiction of Midland County, the State of Texas in any
action, suit or proceeding arising in connection with this Agreement, and
agrees that any such action, suit or proceeding shall be brought only in such
court (and waives any objection based on forum non conveniens or any other
objection to venue therein); provided, however, that such consent to
jurisdiction is solely for the purpose referred to in this paragraph (l) and
shall not be deemed to be a general submission to the jurisdiction of the State
of Texas other than for such purposes.  Each party hereto hereby waives any
right to a trial by jury in connection with any such action, suit or
proceeding.

                 (m)      DESCRIPTIVE HEADINGS.  The descriptive headings used
herein are inserted for convenience of reference only and are not intended to
be part of or to affect the meaning or interpretation of this Agreement.

                 (n)      COUNTERPARTS.  This Agreement may be executed in
counterparts, each of which shall be deemed to be an original, but all of
which, taken together, shall constitute one and the same Agreement.

                 (o)      WITHHOLDINGS.  As may be appropriate, the Company
shall report the payments made hereunder by (i)  filing the appropriate 1099
forms for this amount, and (ii) making any other reports required by law.

                 (p)      TAXES.  Executive agrees to comply, on a timely
basis, with all tax reporting requirements applicable to the receipt of the
payments and other compensation received hereunder and to timely pay all taxes
due with respect to such amounts.

         7.      TERMINATION.  This Agreement shall terminate upon the
termination of the Merger Agreement without any further action on the part of
any party hereto.


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                  [SIGNATURE PAGE TO TERMINATION AGREEMENT]
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         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed as of the day and year first above written.

                                             MARILYN D. WADE



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                                             Address:

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                                             VISTA ENERGY RESOURCES, INC.


                                             By:
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                                             Name:
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                                             Title:
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                                             Address:

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                                             MIDLAND RESOURCES, INC.


                                             By:
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                                             Name:
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                                             Title:
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                                             Address:

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                  [SIGNATURE PAGE TO TERMINATION AGREEMENT]