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            SECOND AMENDMENT TO CREDIT AGREEMENT
  
  
         THIS SECOND 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");
  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") and The Bank of New York, The Bank of Nova Scotia,
  Bankers Trust Company, Canadian Imperial Bank of Commerce, The First
  National Bank of Chicago, NationsBank of Texas, N.A. and Royal Bank of
  Canada as co-agents (in such capacity, together with their successors in
  such capacity, the Co-Agents").
  
  
                       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 as amended by First
  Amendment to Credit Agreement dated as of September 16, 1996
  (collectively, 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," "Co-Agents," "Documentation Agent" and
  Syndication Agent" shall have the meaning indicated above.
  
    3.   The definitions of "Agent", "Agreement", "Applicable Margin" and
  "Revolving Credit Termination Date" in Section 1.02 of the Credit
  Agreement are hereby amended to read as follows:
  
  
         "Agents" shall  mean the Administrative Agent, the
      Syndication Agent and/or the Auction Agent and the Co-Agents.
  
         "Agreement" shall mean this Credit Agreement as amended by
      First Amendment and Second Amendment, as the same may from time
      to time be amended or supplemented.
  
         "Applicable Margin" shall mean the following rates per
      annum as are applicable based upon the Debt to Capital Ratio
      calculated as of the last day of a fiscal quarter of the Company
      to be effective for any Committed Loan outstanding or for the
      facility fee during the period from the Financial Statement
      Delivery Date following such fiscal quarter to but not including
      the next succeeding Financial Statement Delivery Date:
  
  
  
                              
                               Debt to Capital Ratio
                              
                                             
  Greater than                            
  or equal to                  25%     35%     45%      Over
  but less than       25%      35%     45%     55%       55%  
                              
    Facility Fee     .090%    .110%   .125%    .150%    .200%
                              
                              
   Eurodollar Loans .210%    .240%    .275%   .325%     .450%
                              
                              
   Base Rate Loans    0%        0%      0%     0%         0%
                               
  
         "Revolving Credit Termination Date" shall mean, unless the
      Commitments are sooner terminated pursuant to Sections 2.03(a)
      or 10.02, June 27, 2002.
    
    4.   Section 1.02 of the Credit Agreement is hereby supplemented,
  where alphabetically appropriate, with the addition of the following
  definitions:
  
         "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."     
  
         "Second Amendment" shall mean that certain Second
      Amendment to Credit Agreement dated as of June 27, 1997, among
      the Company, the Lenders and the  Agents." 
  
    5.   Section 2.02(b) of the Credit Agreement is hereby amended to read
  as follows:
  
         "(b) Minimum Amounts.  All Borrowings of Base Rate Loans
      shall be in amounts of at least $5,000,000 or the remaining
      balance of the Aggregate Commitments, if less, or any whole
      multiple of $1,000,000 in excess thereof, and all Borrowings in
      the form of Eurodollar Loans shall be in amounts of at least
      $5,000,000 or any whole multiple of $1,000,000 in excess
      thereof."
  
    6.   Section 2.09(h) of the Credit Agreement is hereby deleted in its
  entirety.
  
    7.   Section 8.08 of the Credit Agreement is hereby amended by
  substituting "25%" for "15%" in the first sentence of such section.
  
    8.   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 $1,000,000,000."
  
    9.   The second sentence of Section 11.01 of the Credit Agreement is
  hereby amended to read as follows:
  
         "The Syndication Agent, Documentation Agent and Co-Agents,
      in such capacities, shall have no duties or responsibilities and
      shall incur no liabilities under the Loan Documents."
  
    10.  Attached to this Amendment is a new Annex 1 to the Credit
  Agreement.
  
    11.  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 and
      accrued interest, and the Company will pay accrued fees on June 30,
      1997 and, within 30 days of presentation of a bill by each Lender,
      other expenses due under the Credit Agreement, including without
      limitation, payment of breakage costs under Section 5.05 of the Credit
      Agreement in connection with this prepayment of the Loans;
  
         (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 extent necessary 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.
  
    12.  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.
  
    13.  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.
  
    14.  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.
  
    15.  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.
  
    16.  The Lenders listed on Annex 1 attached hereto are for all
  purposes Lenders under the Loan Documents.
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    IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
  be executed as of June 27, 1997.
  
  
  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 NEW YORK                    
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE BANK OF NOVA SCOTIA
  
  
                                  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:                        
  
  
                                  NATIONSBANK OF TEXAS, N.A.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:         
  
  
                                  ROYAL BANK OF CANADA
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  CAISSE NATIONALE DE CREDIT
                                    AGRICOLE
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE FUJI BANK, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE INDUSTRIAL BANK OF JAPAN
                                    TRUST COMPANY
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE LONG-TERM CREDIT BANK OF
                                    JAPAN, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  MELLON BANK, N.A.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:
  
  
                                  THE SANWA BANK, LIMITED
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  TORONTO DOMINION (TEXAS), INC.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:         
  
  
                                  UNION BANK OF SWITZERLAND
                                  HOUSTON AGENCY
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  THE BANK OF TOKYO-MITSUBISHI, LTD.
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  DRESDNER BANK AG NEW YORK
                                  AND GRAND CAYMAN BRANCHES
  
  
                                  By:_____________________________
                                  Name:
                                  Title:                        
  
  
                                  By:_____________________________
                                  Name:
                                  Title:

                                 CREDIT LYONNAIS NEW YORK BRANCH
  
  
                                  By:_____________________________
                                  Name:
                                  Title:

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