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                                                                    EXHIBIT 10.1


                            MUTUAL RELEASE AND WAIVER

     MUTUAL RELEASE AND WAIVER dated as of December 23, 1998 (this "Agreement"),
     between Rutherford-Moran Oil Corporation (the "Company"), Rutherford-Moran
     Exploration Company, Thai Romo Holdings, Inc. and Thai Romo Limited
     (collectively, the "Obligors"), The Chase Manhattan Bank ("Chase") and
     Chase Securities Inc. ("CSI").

     WHEREAS the Obligors and Chase, as lender and as Administrative Agent, are
     parties to a Second Amended and Restated Credit Agreement dated as of
     September 28, 1998 (the "Second Amended and Restated Credit Agreement"),
     providing, subject to the term and conditions thereof, for extensions of
     credit to be made by Chase to the Company in an aggregate principal or face
     amount not exceeding $200,000,000; and

     WHEREAS the Company has executed a version of a letter agreement dated as
     of August 13, 1998 and Chase has executed a version of a letter agreement
     dated as of August 4, 1998 (each such letter agreement, and any subsequent
     letter agreement with respect to substantially the same subject matter
     executed by each of the Company and CSI, the "Letter Agreement") pursuant
     to which CSI agreed to act as the Company's exclusive financial advisor in
     connection with a Transaction (as defined in the August 4, 1998 letter
     agreement) (a "Transaction");

     NOW THEREFORE, in consideration of the foregoing and the obligations and
     undertakings set forth below, each of the Obligors agrees with Chase and
     CSI individually and for the express benefit of each such person's
     Affiliates, as follows:

     DEFINITIONS

     1 Except as otherwise defined in this Agreement, terms defined in the
     Second Amended and Restated Credit Agreement are used herein as defined
     therein.

     In addition, for purposes of this Agreement the following terms shall have
     the following meanings:

     "Affiliate" shall mean, with respect to any person, any principal, officer,
     director, member, partner, subsidiary, division, representative, agent,
     attorney or employee of such person, or any entity which, indirectly or
     directly, through one or more intermediaries, controls or is controlled by,
     or is under common control with, such



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     person, or any principal, officer, director, member, partner, subsidiary,
     division, representative, agent, attorney or employee thereof.

     "Claim" shall mean any action, cause of action, suit, debt, sum of money,
     fee, account, reckoning, bond, bill, specialty, covenant, contract,
     controversy, agreement, promise, variance, trespass, damage, judgment,
     extent, execution, claim, or demand whatsoever, in law or in equity.

     "person" shall mean any individual, corporation or any other business
     entity or any government or agency, authority or instrumentality of any
     government.

     MUTUAL RELEASE

     2(a)   The Obligors, in consideration of the terms of this Agreement and
            other good and valuable consideration, receipt of which is hereby
            acknowledged, hereby irrevocably, unconditionally and generally
            release and discharge, and cause each of their Affiliates within the
            control of any of the Obligors to irrevocably, unconditionally and
            generally release and discharge, each of Chase, CSI and their
            respective Affiliates and the heirs, executors, administrators,
            receivers, successors and assigns of any of the foregoing
            (collectively, the "Chase Releasees") from any and all Claims
            against any of the Chase Releasees (other than any (x) Claim arising
            from the breach of this Agreement by any Chase Releasee, (y)
            obligations of Chase arising after the date hereof under the Second
            Amended and Restated Credit Agreement and the agreements executed in
            connection therewith and (z) obligations of CSI arising after the
            date hereof under the Letter Agreement), which the Obligors or any
            of their Affiliates, or any heirs, executors, administrators,
            receivers, successors and assigns thereof, ever had, now have or
            hereafter can, shall or may have, for, upon or by reason of any
            matter, cause or thing whatsoever, in each case from the beginning
            of the world to the date of this Agreement.

      (b)   Chase and CSI, in consideration of the terms of this Agreement and
            other good and valuable consideration, receipt of which is hereby
            acknowledged, hereby irrevocably, unconditionally and generally
            release and discharge, and cause each of their respective Affiliates
            within the control of either of Chase or CSI to irrevocably,
            unconditionally and generally release and discharge, each of the
            Obligors and their respective Affiliates and the heirs, executors,
            administrators, receivers, successors and assigns of any of the
            foregoing (collectively, the "Obligor Releasees") from any and all
            Claims against any of the Obligor Releasees (other than any (x)
            Claim arising from the breach of this Agreement by any Obligor
            Releasee, (y) Claims arising under the Second Amended and Restated
            Credit Agreement and other agreements


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            executed in connection therewith (including, without limitation
            the Second Warrant Agreement and (z) Claims arising under the
            Letter Agreement)), which Chase, CSI or any of their Affiliates,
            or any heirs, executors, administrators, receivers, successors
            and assigns thereof, ever had, now have or hereafter can, shall or
            may have, for, upon or by reason of the Second Amended and
            Restated Credit Agreement or CSI acting as financial advisor in
            connection with a Transaction, in each case from the beginning of
            the world to the date of this Agreement.

     COVENANT NOT TO SUE

     3(a)   The Obligors hereby agree, and agree to cause each of their
            Affiliates within the control of the Obligors, not to sue or pursue
            any other legal or equitable action against any of the Chase
            Releasees with respect to any Claim released pursuant to Clause 2(a)
            of this Agreement.

     (b)    Chase and CSI hereby agree, and agree to cause each of their
            Affiliates within the control of Chase or CSI, as applicable, not to
            sue or pursue any other legal or equitable action against any of the
            Obligor Releasees with respect to any Claim released pursuant to
            Clause 2(b) of this Agreement.

     WAIVER OF SECOND AMENDED AND RESTATED CREDIT AGREEMENT

     4(a)   Waiver. Subject to the satisfaction of the conditions precedent
            specified in Clause 4(c) below, but with effect on and after the
            date hereof, Chase hereby waives compliance by the Obligors with the
            terms of Sections 9.06 and 9.07 of the Second Amended and Restated
            Credit Agreement to permit the Obligors to enter into and perform
            their obligations under a Floating Storage and Offloading System
            Bareboat Charter dated as of August 24, 1998 (the "Bareboat
            Charter") among Watertight Shipping B.V., Thai Romo, Thaipo Limited
            and Palang Sophon Limited.

     (b)    Representations and Warranties. Each Obligor represents and warrants
            to Chase that the representations and warranties set forth in
            Section 8 of the Second Amended and Restated Credit Agreement are
            true and complete on the date hereof (unless otherwise limited to an
            earlier date) as if made on and as of the date hereof and as if each
            reference in said Section 8 to "this Agreement" was made after
            giving effect to this Mutual Release and Waiver.

     (c)    Conditions Precedent. As provided in Clause 4(a) above, the waiver
            in said Clause 4(a) shall become effective, as of the date hereof,
            upon the execution and delivery of this Agreement by each of the
            parties hereto.


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     (d)    Miscellaneous. Except as herein provided, the Second Amended and
            Restated Credit Agreement shall remain unchanged and in full force
            and effect.

     SURRENDER OF WARRANTS

     5      Concurrently with the execution of this Mutual Release and Waiver, 
     the Company is executing an Agreement and Plan of Merger with Chevron
     Corporation and Chevron Thailand Inc, providing for the acquisition of the
     Company. The Agreement and Plan of Merger contains the provision of interim
     financing for the Company to be provided by Chevron Corporation until the
     closing of the acquisition on the terms and conditions specified in the
     Agreement and Plan of Merger, which financing will be subordinated to
     amounts outstanding under the Second Amended and Restated Credit Agreement
     as further amended herein. 

     Based upon the execution of the Agreement and Plan of Merger by all
     parties, which definitive agreement is substantially identical to the draft
     dated December 22, 1998 previously provided to Chase, then simultaneously
     with (i) the closing of the acquisition of the Company, and (ii) the
     Replacement (as defined below) of all of the senior Indebtedness and all
     other obligations owed to Chase under the Second Amended and Restated
     Credit Agreement, Chase shall return to the Company the Stock Units (as
     defined in the Second Warrant Agreement) which represented, as of September
     28, 1998, 2,149,120 shares of common stock, par value $.01 per share, of
     the Company (the "Surrendered Warrants") (provided that a total of
     2,561,400 Stock Units have been delivered to Chase pursuant to the Second
     Warrant Agreement).

     In the event that prior to June 1, 1999, the Company either (i) terminates
     the Purchase Agreement or (ii) advises CSI and Chase in writing that the
     closing of the sale of the Company under the Purchase Agreement will not
     occur on or prior to June 1, 1999, this Clause 5 shall be of no further
     force or effect. 

     "Replacement" shall mean (x) the assumption, in form and substance
     satisfactory to Chase in its sole discretion, by Chevron or an Affiliate of
     Chevron acceptable to Chase in its sole discretion, of all senior
     Indebtedness and all other obligations under the Second Amended and
     Restated Credit Agreement of the Obligors owed to Chase or (y) the
     repayment by an entity satisfactory to Chase, in its sole discretion, of
     all senior Indebtedness and all other obligations under the Second Amended
     and Restated Credit Agreement of the Obligors owed to Chase.


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     GOVERNING LAW

     6      This Agreement shall be governed by, and construed in accordance 
     with, the law of the State of New York.

     COUNTERPARTS

     7      This Agreement may be executed and delivered in counterparts 
     (including by facsimile transmission), each of which will be deemed an 
     original.

     BENDING EFFECT; SURVIVAL

     8      This Agreement shall be binding upon and inure to the benefit of the
     parties hereto and their respective successors and permitted assigns
     forever, and shall survive the termination of the Letter Agreement and the
     Second Amended and Restated Credit Agreement.

     NOTICES

     9      All notices and other communications provided for herein shall be 
     given or made in writing,

            (i)  if to the Obligors:

                     Address for Notices:

                     c/o Rutherford-Moran Oil Corporation   
                     5 Greenway Plaza, Suite 220            
                     Houston, Texas 77046                   
                                                            
                     Attention: Chief Financial Officer     
                     Telephone No.: 713-622-5555            
                     Fax No.: 713-621-7072                  
                     
            (ii) if to CSI or Chase

                     Chase Securities Inc. 
                     270 Park Avenue 
                     New York, New York 10017                         
                                                        
                     Attention: Larry Landry 
                     Telephone No.: 212-270-3800 
                     Fax No.: 212-270-0994                       
                                                        
                     with copies to:                    
                     

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                     The Chase Manhattan Bank        
                     380 Madison Avenue, 9th Floor   
                     New York, New York 10019       
                                                     
                     Attention: Elizabeth A. Kelley  
                     Telephone No.: 212-622-4868 
                     Fax No.: 212-622-4834 

                     and           
                                                     
                     The Chase Manhattan Bank        
                     600 Travis Street, 20th Floor   
                     Houston, Texas 77002-8086       
                                                     
                     Attention: Russell Johnson      
                     Telephone No.: 713-216-5617     
                     Fax No.: 713-216-4295           
                     
     or at such other address as shall be designated by any party to this 
     Agreement to the other parties hereto. 

     WAIVER OF THIS AGREEMENT

     10     The waiver by any person of a specific breach or default of this
     Agreement by any other person party hereto shall not be deemed a waiver of
     any other breach or default. No amendment, waiver or other modification of
     any provision of this Agreement shall be effective unless contained in a
     writing signed by each of the parties hereto.


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    IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
    executed and delivered as of the day and year first above written.

    RUTHERFORD-MORAN OIL CORPORATION

    By  /s/ DAVID F. CHAVENSON
       --------------------------------
    Title: VP FINANCE & CFO

    RUTHERFORD-MORAN EXPLORATION
    COMPANY

    By  /s/ DAVID F. CHAVENSON
       --------------------------------    
    Title: VP

    THAI ROMO HOLDINGS, INC

    By  /s/ DAVID F. CHAVENSON
       --------------------------------    
    Title: VP

    THAI ROMO LIMITED

    By  /s/ DAVID F. CHAVENSON
       --------------------------------    
    Title: MANAGING DIRECTOR

    THE CHASE MANHATTAN BANK

    By  /s/ ELIZABETH KELLEY
       --------------------------------    
    Title:


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    CHASE SECURITIES INC.

    By  /s/ R.M. BOWEN, III
       --------------------------------
    Title:


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