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             FIRST AMENDMENT TO CREDIT AGREEMENT
  
  
         THIS FIRST AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is
  among:  ENSERCH EXPLORATION, INC., a corporation formed under the laws of
  the State of Texas (the "Company"); each of the Lenders (as defined in the
  Credit Agreement as hereafter defined) that is a signatory hereto; THE
  CHASE MANHATTAN BANK, a  New York banking corporation (in its individual
  capacity, "Chase"), as administrative agent for the Lenders (in such
  capacity, together with its successors in such capacity, the
  "Administrative Agent"); as auction agent for the Lenders (in such
  capacity, together with its successors in such capacity, the "Auction
  Agent"); and as syndication agent for the Lenders (in such capacity,
  together with its successors in such capacity, the "Syndication Agent")
  and Citibank, N.A.  a national banking association (in its individual
  capacity, "Citibank") and as documentation agent for the Lenders (in such
  capacity, together with its successors in such capacity, the
  "Documentation Agent")  .
  
  
                       R E C I T A L S
  
    A.   The Company, the Agents, and the Lenders  have entered into that
  certain Credit Agreement dated as of May 1, 1995 (the "Credit Agreement"),
  pursuant to which the Lenders have agreed to make certain loans and
  extensions of credit to the Company upon the terms and conditions as
  provided therein; and
  
    B.   The Company, the Agents, and the Lenders now desire to make
  certain amendments to the Credit Agreement.
  
    NOW, THEREFORE, in consideration of the premises and other good and
  valuable consideration and the mutual benefits, covenants and agreements
  herein expressed, the parties hereto now agree as follows:
  
    1.   All capitalized terms used in this Amendment and not otherwise
  defined herein shall have the meanings ascribed to such terms in the
  Credit Agreement.
  
    2.   As used in the Agreement, the terms "Administrative Agent,"
  "Auction Agent," "Citibank," "Documentation Agent" and Syndication Agent"
  shall have the meaning indicated above.
  
    3.   The definitions of  "Agents", "Debt" and "Principal Office" in
  Section 1.02 of the Credit Agreement are hereby amended to read as
  follows:
  
         "Agents" shall mean the Administrative Agent, the
           Auction Agent, the Documentation Agent and the
           Syndication Agent.
  
  
         "Debt" shall mean, for the Company or any Subsidiary
           the sum of the following (without duplication): (i)
           all obligations for borrowed money or evidenced by
           bonds, debentures, mandatorily redeemable preferred
           stock (including such stock of Affiliates) with
           maturities before the Revolving Credit Termination
           Date, notes or other similar instruments (excluding
           interest, fees and charges); (ii) all obligations in
           respect of bankers' acceptances, unreimbursed
           drawings on letters of credit, surety or other
           bonds; (iii) all Capital Lease Obligations; (iv) all
           Operating Lease Obligations; (v) all financial
           guaranties in respect of Debt of unconsolidated
           Affiliates and unrelated Persons; (vi) all
           obligations secured by a Lien on any asset, whether
           or not such Debt is assumed, but excluding
           obligations secured by Liens permitted by Sections
           9.02(c), (e), (f), (h), (i), (j), (k) and (l); (vii)
           all production payments in connection with oil and
           gas properties; and (viii) all Debt of Special
           Entities to the extent the Company or any Subsidiary
           is liable for such Debt under GAAP or such Debt is
           reflected on the consolidated balance sheet of the
           Company or any Subsidiary.  "Debt" shall not include
           Permitted Subordinated Debt."
  
         "Principal Office" shall mean 270 Park Avenue, New
           York, New York 10017.
  
    4.   The definition "Revolving Credit Termination Date" in Section
  1.02 of the Credit Agreement is hereby amended to read as follows:
  
         "Revolving Credit Termination Date" shall mean, unless the
      Commitments are sooner terminated pursuant to Sections 2.03(a)
      or 10.02, August 1, 2001".
  
    5.   Section 1.02 of the Credit Agreement is hereby supplemented,
  where alphabetically appropriate, with the addition of the following
  definition:
  
         "First Amendment" shall mean that certain First Amendment
      to Credit Agreement dated as of September 16, 1996, among the
      Company, the Lenders and the  Agents."          
  
    6.   Section 8.07 of the Credit Agreement is hereby amended to read
  as follows:
  
         "Section 8.07  Lease Payments.  The Company, at its
      option, may cause its obligations to Enserch Exploration
      Holdings, Inc. to be subordinated to the Indebtedness on terms
      substantially similar to the terms set forth on Exhibit M or on
      terms and subject to documentation satisfactory to the
      Administrative Agent.
  
    7.   Section 9.01 of the Credit Agreement is hereby amended to read
  as follows:
  
         "Section 9.01  Debt to Capital Ratio.  The Company will
      not permit its ratio ("Debt to Capital Ratio") expressed as a
      percentage of (i) Debt of the Company and its Consolidated
      Subsidiaries on a consolidated basis ("Consolidated Debt") to
      (ii) the sum of Consolidated Debt plus Net Worth to exceed 60%
      at any time; provided that in no event will Consolidated Debt
      ever exceed $900,000,000."
  
    8.   Section 9.03 of the Credit Agreement is hereby amended by adding
  the following sentence at the end of such Section:
  
    "From and after the date that the Company ceases to be an
      Affiliate of ENSERCH Corporation, neither the Company nor any
      Subsidiary may make loans or advances to ENSERCH Corporation or
      any of its subsidiaries, and any outstanding loans and advances
      to ENSERCH Corporation and its subsidiaries from the Company and
      its Subsidiaries on such date of disaffiliation shall be
      immediately repaid."
         
    9.   Section 10.01(k) of the Credit Agreement is hereby amended to
  read as follows:
  
         "(k) any Change of Control shall occur.  For purposes of
      this Section 10.01(k), "Change of Control" shall mean other than
      Enserch Corporation's ownership, the acquisition by any Person,
      or two or more Persons acting in concert, of beneficial
      ownership (within the meaning of the Securities  Exchange Act of
      1934) of 35% or more of the outstanding share of voting stock of
      the Company."
  
    10.  The first two sentences of Section 11.01 of the Credit Agreement
  are hereby amended to read as follows:
  
    "Each Lender hereby irrevocably appoints and authorizes Chase as
      the Administrative Agent and the Auction Agent to act as its
      agents hereunder and under the other Loan Documents with such
      powers as are specifically delegated to the Administrative Agent
      and the Auction Agent respectively by the terms of this
      Agreement and the other Loan Documents, together with such
      powers as reasonably incidental thereto.  The Syndication Agent
      and Documentation Agent, in such capacities, shall have no
      duties or responsibilities and shall incur no liabilities under
      the Loan Documents."
  
    11.  Attached to this Amendment is a new Annex 1 to the Credit
  Agreement.
  
    12.  This Amendment shall become binding on the Lenders when, and only
  when, the Administrative Agent shall have received each of the following
  in form and substance satisfactory to the Administrative Agent or its
  counsel:
  
         (a)  counterparts of this Amendment executed by the Company, the
      Agents and the Lenders;
  
         (b)  prepayment by the Company of all outstanding Loans, accrued
  interest,   accrued fees and other expenses due under the Credit
                Agreement to September 16, 1996, including without
                limitation, payment of breakage costs under Section 5.05
                of the Credit Agreement in connection with this prepayment
                of the Loans within 10 days of presentation of a bill by
                each Lender;
  
         (c)  refunding of the Loans prepaid in clause (b) above by the
      Lenders set forth on Annex 1 attached hereto in proportion to their
      respective Percentage Shares, with the Administrative Agent netting
      such prepayments and fundings to the extent administratively
      convenient;
  
         (d)  issuance of new Notes to the Lenders on Annex 1 attached
  hereto, duly     completed and executed;
  
         (e)  a certificate of the Secretary or an Assistant Secretary
      of the Company setting forth resolutions of its board of directors with
      respect to the authorization of the Company to execute, deliver and
      perform this Amendment; and
  
         (f)  such other documents as it or its counsel may reasonably
      request.
  
    13.  The parties hereto hereby acknowledge and agree that, except as
  specifically supplemented and amended, changed or modified hereby, the
  Credit Agreement shall remain in full force and effect in accordance with
  its terms.
  
    14.  The Company hereby reaffirms that as of the date of this
  Amendment, the representations and warranties contained in Article VII of
  the Credit Agreement are true and correct on the date hereof as though
  made on and as of the date of this Amendment, except as such
  representations and warranties are expressly limited to an earlier date.
  
    15.  THIS AMENDMENT (INCLUDING, BUT NOT LIMITED TO, THE VALIDITY AND
  ENFORCEABILITY HEREOF) SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE
  WITH, THE LAWS OF THE STATE OF TEXAS, OTHER THAN THE CONFLICT OF LAWS
  RULES THEREOF.
  
    16.  This Amendment may be executed in two or more counterparts, and
  it shall not be necessary that the signatures of all parties hereto be
  contained on any one counterpart hereof; each counterpart shall be deemed
  an original, but all of which together shall constitute one and the same
  instrument.
  
    17.  The Lenders listed on Annex 1 attached hereto are for all
  purposes Lenders under the Loan Documents.
       IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
  be executed as of September 16, 1996.
  
  
  COMPANY:                             ENSERCH EXPLORATION, INC.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
  LENDER AND ADMINISTRATIVE AGENT,     THE CHASE MANHATTAN BANK
   SYNDICATION AGENT AND
  AUCTION AGENT:             
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
  LENDER AND DOCUMENTATION        CITIBANK, N.A.
  AGENT:                          
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
  LENDERS:                             THE BANK OF NOVA SCOTIA
  
  
                                  By:_____________________________
                                  Name:
                                  Title:         
  
  
                                  NATIONSBANK OF TEXAS, N.A.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:         
  
  
                                  ROYAL BANK OF CANADA
  
                                 By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  BANKERS TRUST COMPANY
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  CANADIAN IMPERIAL BANK OF
                                    COMMERCE
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE FIRST NATIONAL BANK OF
                                    CHICAGO
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE BANK OF NEW YORK                    
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE LONG-TERM CREDIT BANK OF
                                    JAPAN, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE BANK OF TOKYO-MITSUBISHI, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  CREDIT LYONNAIS NEW YORK BRANCH
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE INDUSTRIAL BANK OF JAPAN
                                    TRUST COMPANY
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE SANWA BANK, LIMITED
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  CAISSE NATIONALE DE CREDIT
                                    AGRICOLE
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE FUJI BANK, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  TORONTO DOMINION (TEXAS), INC.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:         
  
              
                                  UNION BANK OF SWITZERLAND
                                  HOUSTON AGENCY
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
                                  
                                  DRESDNER BANK AG NEW YORK
                                  AND GRAND CAYMAN BRANCHES
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
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BANKS THAT WILL NO LONGER BE LENDERS AS OF SEPTEMBER 16, 1996.
  
  
                                  NATIONAL WESTMINSTER BANK PLC
                                  NEW YORK BRANCH
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  NATIONAL WESTMINSTER BANK PLC
                                  NASSAU BRANCH
  
  
                                  By:_____________________________
                                  Name:
                                  Title:    
  
  
                                  WESTDEUTSCHE LANDESBANK
                                    GIROZENTRALE
  
  
                                  By:_____________________________
                                  Name:
                                  Title:    
  
  
                                  By:_____________________________
                                  Name:
                                  Title:    
  
                                      TEXAS COMMERCE BANK NATIONAL
                                    ASSOCIATION
  
  
                                  By:_____________________________
                                  Name:
                                  Title:    
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