FIRST AMENDMENT TO RIGHTS AGREEMENT

         This FIRST  AMENDMENT TO RIGHTS  AGREEMENT,  dated as of July ___, 1997
(the "Amendment"),  between CAIRN ENERGY USA, INC., a Delaware  corporation (the
"Company"), and STOCK TRANSFER COMPANY OF AMERICA, INC., a Delaware corporation,
as Rights Agent (the "Rights Agent").

                                    RECITALS

     1. The Company and the Rights Agent executed a Rights Agreement as of April
1, 1997 (the "Rights Agreement").

     2. The Board of Directors of the Company has concurrently herewith approved
a certain Agreement and Plan of Merger with The Meridian Resource Corporation, a
corporation  formed  under  the laws of the  State of  Texas  ("Parent"),  and C
Acquisition  Corp., a corporation formed under the laws of the State of Delaware
and a  wholly-owned  subsidiary of Parent (the "Sub") (the Agreement and Plan of
Merger,  as amended  from time to time being  herein  referred to as the "Merger
Agreement").

     3. The Board of  Directors  of the  Company  believes  it to be in the best
interest of the  Company to amend the Rights  Agreement,  effective  immediately
prior to the execution and delivery of the Merger Agreement.

                                    AGREEMENT

     Accordingly,  in  consideration  of the premises  and the mutual  agreement
herein set forth the parties hereby agree as follows:

     1. The Rights  Agreement is hereby amended by the amendment of Section 7(a)
so as to read in its entirety as follows:

         "(a) Except as  otherwise  provided  herein,  the Rights  shall  become
         exercisable  on the  Distribution  Date,  and thereafter the registered
         holder of any Right  Certificate  may,  subject  to  Section  11(a)(ii)
         hereof and except as  otherwise  provided  herein,  exercise the Rights
         evidenced  thereby  in whole or in part  upon  surrender  of the  Right
         Certificate,  with the form of election to purchase on the reverse side
         thereof duly  executed,  to the Rights Agent at the office or agency of
         the Rights Agent designated for such purpose,  together with payment of
         the  aggregate  Purchase  Price with respect to the total number of one
         one-  thousandths of a share of Preferred  Stock (or other  securities,
         cash or other  assets,  as the case may be) as to which the  Rights are
         exercised,  at any time which is both after the  Distribution  Date and
         prior to the time (the  "Expiration  Date") that is the earliest of (i)
         the Close of Business on March 31, 2007 (the "Final Expiration  Date"),
         (ii) the time at which the Rights are  redeemed  as provided in Section
         23 hereof (the "Redemption Date"), (iii)

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         the time at which such Rights are  exchanged  as provided in Section 24
         hereof or (iv)  immediately  prior to the Effective Time (as defined in
         the Merger Agreement (as defined in Section 35 hereof)).

     2. The Rights  Agreement is hereby further amended by the addition  thereto
of a new Section 35. Merger Agreement with The Meridian Resource Corporation. to
be and read as follows:

         "Section 35. Merger Agreement with The Meridian  Resource  Corporation.
         Notwithstanding  any other provision of this  Agreement,  the approval,
         execution  and  delivery by the Company of that certain  Agreement  and
         Plan of Merger dated as of July __, 1997, by and among the Company, The
         Meridian Resource  Corporation,  a corporation formed under the laws of
         the State of Texas ("Parent"),  and C Acquisition  Corp., a corporation
         formed  under  the laws of the  State of  Delaware  and a  wholly-owned
         subsidiary of Parent (the "Sub") (said Agreement and Plan of Merger, as
         amended  from time to time,  being  herein  referred  to as the "Merger
         Agreement"),  and  the  consummation  of the  transaction  contemplated
         thereby, shall not, solely by reason thereof:
                           (a)  cause any person to be or to become an Acquiring
                  Person under the terms and provisions of this Agreement;
                           (b)  cause  there to occur a Flip-In  Event,  a Stock
                  Acquisition  Date, a Distribution  Date or an event  described
                  under Section 13(a) of this Agreement; or
                           (c)  cause the Rights to become exercisable under any
                  provision of this Agreement.

     3. This  Amendment  may be  executed in one or more  counterparts,  each of
which shall be deemed to be an original,  but all of which shall  constitute one
and the same agreement.







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



                                       CAIRN ENERGY USA, INC.


                                       By:
                                          -----------------------------------
                                          Michael R. Gilbert
                                          President



                                          STOCK TRANSFER COMPANY OF AMERICA,
                                           INC., as Rights Agent


                                       By:
                                          -----------------------------------
                                          Jeanette Fitzgerald
                                          Vice President

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