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                                                                   EXHIBIT 10.13

                            SECOND AMENDMENT TO THE
                          UNITED MERIDIAN CORPORATION
            1994 OUTSIDE DIRECTORS' NONQUALIFIED STOCK OPTION PLAN

   This Second Amendment ("Third Amendment") to the United Meridian Corporation
1994 Outside Directors' Nonqualified Stock Option Plan (the "Plan") hereby
amends the Plan as follows effective as of _______________, 1996 (the "Effective
Date"):

   1.     Section 4(e) of the Plan is amended and restated in its entirety to
          read as follows:

                "(e)  Manner of Exercise.  Option Shares purchased upon
          exercise of options shall at the time of purchase be paid for in full.
          The Company shall satisfy its employment tax and other tax withholding
          obligations by requiring the optionee (or such optionee's estate or
          representative) to pay the amount of employment tax and withholding
          tax, if any, that must be paid under federal, state and local law due
          to the exercise of the option.  To the extent that the right to
          purchase shares has accrued hereunder, options may be exercised from
          time to time by written notice to the Company stating the full number
          of shares with respect to which the option is being exercised and the
          time of delivery thereof, which shall be at least fifteen days after
          the giving of such notice unless an earlier date shall have been
          mutually agreed upon by the optionee (or other person entitled to
          exercise the option) and the Company, accompanied by payment to the
          Company of the purchase price in full and the amount of employment tax
          and withholding tax due, if any, upon the exercise of the option.
          Such payment shall be effected (i) by certified or official bank
          check, (ii) by the delivery of a number of shares of Common Stock
          (plus cash if necessary) having a fair market value equal to the
          amount of such purchase price and employment or withholding tax
          (subject to such restrictions or procedures as the Company deems
          necessary to satisfy Section 16(b) of the Securities Exchange Act of
          1934, as amended (the "Exchange Act")) or (iii) by delivery of the
          equivalent thereof acceptable to the Company.  The Company will, as
          soon as reasonably possible notify the optionee (or such optionee's
          representative) of the amount of employment tax and other withholding
          tax that must be paid under federal, state and local law due to the
          exercise of the option.  At the time of delivery, the Company shall,
          without transfer or issue tax to the optionee (or other person
          entitled to exercise the option), deliver to the optionee (or to such
          other person) at the principal office of the Company, or such other
          place as shall be mutually agreed upon, a certificate or certificates
          for the Option Shares, provided, however, that the time of delivery
          may be postponed by the Company for such period as may be required for
          it with reasonable diligence to comply with any requirements of law."

   2.     Section 4(f) of the Plan is amended and restated in its entirety to
          read as follows:

                "(f) Assignability of Options. Options granted hereunder may be
          transferred by the optionee thereof to one or more permitted
          transferees; provided that (i) there may be no consideration for such
          transfer, (ii) the optionee (or such 

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          optionee's estate or representative) shall remain obligated to satisfy
          all employment tax and other withholding tax obligations associated
          with the exercise of the options, (iii) the optionee shall notify the
          Company in writing that such transfer has occurred, the identity and
          address of the permitted transferee and the relationship of the
          permitted transferee to the optionee and (iv) of such transfer shall
          be effected pursuant to transfer documents approved from time to time
          by the Committee. To the extent an option transferred pursuant to this
          Section 4(f) is not fully exercisable as of the date of transfer
          thereof, the optionee shall specify in the transfer document whether
          and to what extent the transferred options (if less than all of the
          options subject to the applicable Nonqualified Stock Option Agreement)
          are exercisable, subject to the limitations on exercisability
          contained in the applicable Nonqualified Stock Option Agreement.
          Furthermore, to the extent the optionee transfers options that are not
          exercisable as of the date of transfer and such options are less than
          all of the options subject to the applicable Nonqualified Stock Option
          Agreement, the optionee shall specify in the transfer documents,
          subject to the limitations on exercisability contained in the
          applicable Nonqualified Stock Option Agreement, when the transferred
          options become exercisable as options under the applicable
          Nonqualified Stock Option Agreement generally become exercisable
          subsequent to such transfer. Any permitted transferee may not further
          assign or transfer the transferred option otherwise than by will or
          the laws of the descent and distribution. Following any permitted
          transfer, any such options shall continue to be subject to the same
          terms and conditions as were applicable immediately prior to transfer;
          provided that for purposes of Sections 4(i), 4(j) and 4(k) hereof the
          term "optionee" shall be deemed to refer also to each permitted
          transferee. The events of termination of relationship in Section 4(g)
          hereof shall continue to be applied with respect to the Optionee,
          following which the options shall be exercisable by the transferee
          only to the extent, and for the periods specified in Section 4(g). The
          term "permitted transferees" shall mean one or more of the following:
          (i) any member of the optionee's immediate family; (ii) a trust
          established for the exclusive benefit of one or more members of such
          immediate family; or (iii) a partnership in which such immediate
          family members are the only partners. The term "immediate family" is
          defined for such purpose as spouses, children, stepchildren and
          grandchildren, including relationships arising from adoption.

   3.     Section 5(a) of the Plan is amended and restated in its entirety to
          read as follows:

                "(a) The Plan shall be administered by the Committee on
          Directors (the "Committee") consisting of not less than three (3) non-
          employee directors (as defined in Rule 16b-3 promulgated under the
          Exchange Act). The members of the Committee shall be appointed by the
          Board of Directors. The Board of Directors may, from time to time,
          remove members from or add members to the Committee. Vacancies in the
          Committee, however caused, shall be filled by the Board of Directors.
          The Committee shall select one of its members as chairman and shall
          hold meetings at such times and places as it may determine. The
          Committee may appoint a secretary and, subject to the provisions of
          the Plan and to policies determined by the Board of Directors of the
          Company, may make such 

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          rules and regulations for the conduct of its business as it shall deem
          advisable. A majority of the Committee shall constitute a quorum. All
          actions of the Committee shall be taken by a majority of its members.
          Any action may be taken by a written instrument signed by a majority
          of the members, and action so taken shall be fully as effective as if
          it had been taken by a vote of the majority of the members at a
          meeting duly called and held."

   4.     Each Nonqualified Stock Option Agreement ("Option Agreement") entered
into prior to the Effective Date of this Third Amendment shall be amended as
follows:

          a.  Section 2 of each Option Agreement is amended and restated in its
entirety to read as follows:

          "2. Assignability of Option.  This option is transferable to
     the extent permitted under the Plan."

          b.  Section 3 of the Option Agreement is amended and restated in its
entirety to read as follows:

          "3. Manner of Exercise. The Optionee (or other person entitled to
     exercise this option) shall purchase shares of stock of the Company subject
     hereto by the payment to the Company of the purchase price in full and the
     amount of employment tax and withholding tax due, if any, upon the exercise
     of the option (i) by certified or official bank check, (ii) by the delivery
     of a number of shares of Common Stock (plus cash if necessary) having a
     fair market value equal to the amount of such purchase price and employment
     and withholding tax, or (iii) by delivery of the equivalent thereof
     acceptable to the Company. Any employment or withholding tax due upon
     exercise of this option shall be, and shall remain, the responsibility of
     the Optionee (or such Optionee's estate or representative). This option may
     be exercised from time to time by written notice to the Company stating the
     full number of shares to be purchased and the time and delivery thereof,
     which shall be at least fifteen days after the giving of notice unless an
     earlier date shall have been agreed upon between the Optionee (or other
     person entitled to exercise this option) and the Company, accompanied by
     full payment for the shares as described in the first sentence of this
     Section 3. The Company will, as soon as is reasonably possible, notify the
     Optionee (or such Optionee's representative) of the amount of employment
     tax and other withholding tax, if any, that must be paid under federal,
     state and local law due to the exercise of the option. The Company shall
     have no obligation to deliver certificates for the shares purchased until
     the Optionee (or such Optionee's representative) pays to the Company the
     purchase price in full and the amount of employment tax and withholding tax
     specified in the Company's notice as described in this Section 3 by payment
     terms set forth in the first sentence of this Section 3. At the time of
     delivery, the Company shall, without transfer or issue tax to the Optionee
     (or other person entitled to exercise this option) deliver at the principal
     office of the Company, or at such other place as shall be mutually agreed
     upon, a certificate or certificates for such shares, provided, however,
     that the time of delivery may be postponed by the Company for such period
     as may be required for it to comply with reasonable diligence with any
     requirements of law."

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   5.    Appendix A to the Plan is amended and restated to read as set forth in
Appendix A to this Second Amendment.


Date:  _______________________

                                UNITED MERIDIAN CORPORATION



                                By:______________________________________
                                Name:____________________________________
                                Title:___________________________________

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