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                                                                    Exhibit 10.7

                      FIRST AMENDMENT TO CREDIT AGREEMENT
                      -----------------------------------


     THIS FIRST AMENDMENT TO CREDIT AGREEMENT (herein called this "Amendment")
is made as of the 15th day of November, 2000 by and among Key Production
Company, Inc. ("Borrower"), and Bank of America, N.A. ("Agent"), and the Lenders
under the Credit Agreement referred to below.

                             W I T N E S S E T H:

     WHEREAS, Borrower, Agent, and Lenders have entered into that certain Credit
Agreement dated as of November 12, 1999 (as amended, restated, or supplemented
to the date hereof, the "Original Agreement"), for the purposes and
consideration therein expressed, pursuant to which Lenders made and became
obligated to make loans to Borrower as therein provided;

     WHEREAS, Borrower, Agent, and Lenders desire to amend the Original
Agreement for the purposes described herein;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
and agreements contained herein and in the Original Agreement, in consideration
of the loans which may hereafter be made by Lenders to Borrower, and for other
good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto do hereby agree as follows:

                                  ARTICLE I.

                          Definitions and References
                          --------------------------

     (S)  1.1.  Defined Terms.  Unless the context otherwise requires or unless
                -------------
otherwise expressly defined herein, the terms defined in the Original Agreement
shall have the same meanings whenever used in this Amendment.  As used herein,
the following terms shall have the following meanings:

     "Amendment" means this First Amendment to Credit Agreement.
      ---------

     "Columbus Acquisition" means the consummation of the transactions described
      --------------------
in the Merger Agreement.

     "Merger Agreement" means the Agreement and Plan of Merger dated as of
      ----------------
August 28, 2000 among Borrower, Key Acquisition Two, Inc., a Colorado
corporation and wholly-owned subsidiary of Borrower, and Columbus Energy Corp.,
a Colorado corporation.

     "Credit Agreement" means the Original Agreement as amended by this
      ----------------
Amendment.

                                  ARTICLE II.
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                          Amendments; Borrowing Base
                          --------------------------

     (S) 2.1.  Commitment Period.  The definition of "Commitment Period"
               -----------------
contained in Section 1.1 of the Original Agreement is hereby amended in its
entirety to read as follows:

               "'Commitment Period' means the period from and including the date
                 -----------------
     hereof until July 1, 2002 (or, if earlier, the day on which the obligations
     of Lenders to make Loans hereunder or the obligations of LC Issuer to issue
     Letters of Credit hereunder have been terminated or the Notes first become
     due and payable in full)."

     (S) 2.2.  Principal Payments.  Section 2.6 of the Original Agreement is
               ------------------
hereby amended in its entirety to read as follows:

               "Section 2.6.  Regularly Scheduled Principal Payments. Borrower
                              --------------------------------------
     shall repay the principal balance of the Loans in fourteen (14) quarterly
     installments, each in an amount equal to one-fourteenth (1/14) of the
     aggregate principal balance of all Loans outstanding on the last day of the
     Commitment Period. Such installments shall be due and payable on each Base
     Rate Payment Date, beginning with the first Base Rate Payment Date which
     occurs after the end of the Commitment Period and ending on the Maturity
     Date."

     (S) 2.3.  Borrowing Base. Agent and Lenders hereby notify Borrower that
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until the next Determination Date the Borrowing Base shall be $100,000,000;
provided that upon the consummation of the Columbus Acquisition, the Borrowing
Base shall be automatically increased by the Columbus Borrowing Base Amount (as
defined below) which increase shall remain in effect until the next
Determination Date without any further action on behalf of Agent or Lenders.  As
used in this section " Columbus Borrowing Base Amount" means $10,000,000;
provided, however, that such amount may be reduced by Agent and Lenders in the
event that for any reason any interest in any property reviewed by Agent and
Lenders for inclusion in the Borrowing Base is not acquired by the Related
Persons as part of the Columbus Acquisition.


                                 ARTICLE III.

                          Conditions of Effectiveness
                          ---------------------------

     (S) 3.1.  Effective Date.  This Amendment shall become effective as of the
               --------------
date first above written when Agent shall have received all of the following:

               (a)  This Amendment, duly authorized, executed and delivered by
     Borrower, Agent, and each Lender, and in form and substance satisfactory to
     Agent.

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               (b)  A certificate of a duly authorized officer of Borrower dated
     the date of this Amendment certifying: (i) that all of the representations
     and warranties set forth in Article IV hereof are true and correct at and
     as of the time of such effectiveness; and (ii) as to such other corporate
     matters as Agent shall deem necessary.

               (c)  A written legal opinion of in-house counsel for Borrower,
     dated as of the date of this Amendment, addressed to Agent, to the effect
     that this Amendment has been duly authorized, executed and delivered by
     Borrower and that the Credit Agreement and each other Loan Document, as
     affected hereby, to which any Restricted Person is a party constitutes the
     legal, valid and binding obligation of each such Restricted Person,
     enforceable in accordance with their terms (subject, as to enforcement of
     remedies, to applicable bankruptcy, reorganization, insolvency and similar
     laws and to general principles of equity) and such other matters of Agent
     may require.

               (d)  Payment of fees and disbursements of Thompson & Knight
     L.L.P. relating to this Amendment and the Credit Agreement as provided in
     the Credit Agreement.

               (e)  Agent shall have additionally received such other documents
     as Agent may reasonably request.


                                  ARTICLE IV.

                        Representations and Warranties
                        ------------------------------

     (S) 4.1.  Representations and Warranties of Borrower.  In order to induce
               ------------------------------------------
each Lender to enter into this Amendment, Borrower represents and warrants on
the date hereof and as of the Effective Date to each Lender that:

               (a)  The representations and warranties contained in Article V of
     the Original Agreement are true and correct at and as of the time of the
     effectiveness hereof (except as such representations and warranties have
     been modified by the transactions contemplated herein).

               (b)  Borrower is duly authorized to execute and deliver this
     Amendment and Borrower is and will continue to be duly authorized to borrow
     monies and to perform its obligations under the Credit Agreement. Borrower
     has duly taken all corporate action necessary to authorize the execution
     and delivery of this Amendment.

               (c)  The execution and delivery by Borrower of this Amendment,
     the performance of its obligations hereunder and the consummation of the
     transactions contemplated hereby do not and will not conflict with any
     provision of law, statute, rule or regulation or of the certificate of
     incorporation and bylaws of Borrower or of any material agreement,
     judgment, license, order or permit applicable to or binding upon Borrower
     or

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     result in the creation of any lien, charge or encumbrance upon any assets
     or properties of Borrower. Except for those which have been obtained, no
     consent, approval, authorization or order of any court or governmental
     authority or third party is required in connection with the execution and
     delivery by Borrower of this Amendment.

               (d)  When duly executed and delivered, this Amendment, the Credit
     Agreement, and each other Loan Document, as affected hereby, will be a
     legal and binding obligation of each Restricted Person that is a party
     hereto and thereto enforceable against such Restricted Person in accordance
     with its terms, except as limited by bankruptcy, insolvency or similar laws
     of general application relating to the enforcement of creditors' rights and
     by equitable principles of general application.

               (e)  The audited Consolidated financial statements of Borrower
     dated as of December 31, 1999 and the unaudited Consolidated financial
     statements of Borrower dated as of June 30, 2000 fairly present the
     Consolidated financial position at such dates of Borrower and the
     Consolidated statement of operations and the changes in Consolidated
     financial position for the periods ending on such dates for Borrower.
     Copies of such financial statements have heretofore been delivered to
     Agent. Since June 30, 2000, no material adverse change has occurred in the
     financial condition or business or in the Consolidated financial condition
     or business of Borrower.


                                  ARTICLE V.

                                 Miscellaneous
                                 -------------

     (S) 5.1.  Ratification of Agreements.  The Original Agreement as hereby
               --------------------------
amended is hereby ratified and confirmed in all respects. Any reference to the
Credit Agreement in any Loan Document shall be deemed to be a reference to the
Original Agreement as hereby amended. The Loan Documents, as they may be amended
or affected by this Amendment, are hereby ratified and confirmed in all
respects. The execution, delivery and effectiveness of this Amendment shall not,
except as expressly provided herein, operate as a waiver of any right, power or
remedy of Lenders under the Credit Agreement, the Notes, or any other Loan
Document nor constitute a waiver of any provision of the Credit Agreement, the
Notes, or any other Loan Document.

     (S) 5.2.  Survival of Agreements.  All representations, warranties,
               ----------------------
covenants and agreements of Borrower herein shall survive the execution and
delivery of this Amendment and the performance hereof, including without
limitation the making or granting of the Loans, and shall further survive until
all of the Obligations are paid in full. All statements and agreements contained
in any certificate or instrument delivered by Borrower hereunder or under the
Credit Agreement to any Lender shall be deemed to constitute representations and
warranties by, and/or agreements and covenants of, Borrower under this Amendment
and under the Credit Agreement.

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     (S) 5.3.  Loan Documents.  This Amendment is a Loan Document, and all
               --------------
provisions in the Credit Agreement pertaining to Loan Documents apply hereto.

     (S) 5.4.  Governing Law.  This Amendment shall be governed by and construed
               -------------
in accordance the laws of the State of Texas and any applicable laws of the
United States of America in all respects, including construction, validity and
performance.

     (S) 5.5.  Counterparts.  This Amendment may be separately executed in
               ------------
counterparts and by the different parties hereto in separate counterparts, each
of which when so executed shall be deemed to constitute one and the same
Amendment.

     THIS AMENDMENT AND THE OTHER LOAN DOCUMENTS REPRESENT THE FINAL AGREEMENT
BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR,
CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO
UNWRITTEN ORAL AGREEMENTS OF THE PARTIES.

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     IN WITNESS WHEREOF, this Amendment is executed as of the date first above
written.



                                        KEY PRODUCTION COMPANY, INC.



                                        By:_____________________________________
                                           Name:
                                           Title:
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                                   BANK OF AMERICA, N.A., as Agent and Lender



                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   U.S. BANK NATIONAL ASSOCIATION,
                                   a Lender



                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   BANK ONE, N.A., a Lender



                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   CIBC, INC., a Lender



                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   BANK OF OKLAHOMA, N.A., a Lender



                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   UNION BANK OF CALIFORNIA, N.A., a Lender



                                   By:__________________________________________
                                      Name:
                                      Title:


                                   By:__________________________________________
                                      Name:
                                      Title:
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                                   BNP PARIBAS, a Lender



                                   By:__________________________________________
                                      Name:
                                      Title: