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                                                                   EXHIBIT 10.10

           THIRD AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT



          THIS THIRD AMENDMENT TO AMENDED AND RESTATED CREDIT AGREEMENT (the
"Third Amendment") made and entered into the 3rd day of February, 1997, by and
between AMERAC ENERGY CORPORATION, a Delaware corporation, and BANK ONE, TEXAS,
NATIONAL ASSOCIATION, a national banking association.

                                 W I T N E S S E T H:
                                 - - - - - - - - - -

          WHEREAS, the above named parties did execute and exchange counterparts
of that certain Amended and Restated Credit Agreement dated as of May 12, 1995
as amended by that certain First Amendment to Amended and Restated Credit
Agreement dated January 16, 1996 and that certain Second Amendment to Amended
and Restated Credit Agreement dated August 15, 1996 (collectively, the
"Agreement") to which reference is here made for all purposes;

          WHEREAS, the above named parties are desirous of amending the
Agreement in the particulars hereinafter set forth;

          NOW THEREFORE, in consideration of the mutual covenants and agreements
of the parties to the Agreement and agreements of the parties hereto as set
forth in this Third Amendment, the parties hereto agree as follows:
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                                   ARTICLE I
                                  DEFINITIONS

          As used herein, each term defined in the Agreement shall have the
meaning assigned thereto in the Agreement and terms defined herein shall be
incorporated into the Agreement unless expressly provided to the contrary.

                                  ARTICLE II
                                  AMENDMENTS

          2.01  The Agreement is hereby amended to substitute for the definition
of "Commitment Limit" in Section 1.1 of the Agreement the following definition,
to wit:
          "Commitment Limit" means the lesser of (a) $50,000,000.00 or (b) the
          Borrowing Base.

          2.02  The Agreement is hereby amended to substitute for the definition
of "Note" in Section 1.1 of the Agreement the following definition, to wit:

          "Note" means that certain promissory note in the face amount of
          $50,000,000.00 dated February 3, 1997 made by the Borrower to the
          order of the Lender, together with all deferrals, renewals or
          extensions thereof, which promissory note shall evidence the Advances
          made to the Borrower by the Lender pursuant to Section 2.1 and funds
          advanced and applied pursuant to Section 2.10.

          2.03  The Agreement is hereby amended to substitute for the definition
of "Termination Date" in Section 1.1 of the Agreement the following definition,
to wit:
          "Termination Date" means June 30, 1999.

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                                  ARTICLE III
                             CONDITIONS PRECEDENT

          The execution of this Third Amendment by the Lender is subject to the
condition precedent that the Lender shall have received all of the following,
each duly executed and in form and substance satisfactory to the Lender:

          (a)  the Note, in the form of Exhibit A attached hereto;

          (b)  this Third Amendment;

          (c)  as to the Mortgaged Properties located in Texas and previously
               encumbered by the Lender in favor of the Borrower;

                         a Ratification of and Amendment to Deed of Trust,
                    Security Agreement, Financing Statement and Assignment of
                    Production between the Borrower and the Lender;

          (d)  as to the Mortgaged Properties located in Oklahoma and Kansas and
               previously encumbered by the Lender in favor of the Borrower;

                         a Ratification of and Amendment to Mortgage, Deed of
                    Trust, Security Agreement, Financing Statement and
                    Assignment of Production between the Borrower and the
                    Lender;

          (e)  a copy of the corporate resolutions of the Borrower approving
               this Third Amendment, the Note and the other Loan Documents set
               forth in this Third Amendment and authorizing the transactions
               contemplated in this Third Amendment, duly adopted by its board
               of directors and accompanied by a certificate of the secretary or
               an assistant secretary of

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               the Borrower to the effect that such copy is a true and correct
               copy of resolutions duly adopted by written consent or at a
               meeting of the board of directors, that such resolutions
               constitute all the resolutions adopted with respect to such
               transactions, and that such resolutions have not been amended,
               modified or revoked in any respect, and are in full force and
               effect as of the date hereof; and

          (f)  a copy of the articles of incorporation and by-laws of the
               Borrower accompanied by a certificate of the secretary or
               assistant secretary of the Borrower to the effect that such
               copies are correct and complete.

                                  ARTICLE IV
                        REPRESENTATIONS AND WARRANTIES

          The Borrower hereby expressly remakes in favor of the Lender all of
the representations and warranties set forth in ARTICLE 4 of the Agreement, as
amended hereby, and represents and warrants that all such representations and
warranties remain true and unbreached, except as affected by the transactions
contemplated in the Agreement.

                                   ARTICLE V
                                 RATIFICATION

          Each of the parties hereto does hereby adopt, ratify and confirm the
Agreement, in all things in accordance with the terms and provisions thereof, as
modified or amended by this Third Amendment.

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                                  ARTICLE VI
                                 MISCELLANEOUS

          6.01  All references to the Agreement in any document heretofore or
hereafter executed in connection with the transactions contemplated in the
Agreement shall be deemed to refer to the Agreement as amended by this Third
Amendment.

          6.02  THIS THIRD AMENDMENT SHALL BE DEEMED TO BE A CONTRACT MADE
UNDER, AND SHALL BE CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF
TEXAS.
          IN WITNESS WHEREOF, this Third Amendment to Amended and Restated
Credit Agreement is executed as of the date first above written.


                                  AMERAC ENERGY CORPORATION


                                  By:
                                      ----------------------------------
                                      Richard B. Hallett
                                         Vice President and
                                         Chief Financial Officer


                                    BANK ONE, TEXAS, NATIONAL
                                      ASSOCIATION


                                  By:
                                      ------------------------------------
                                      Jeffrey W. Baker
                                         Vice President

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