FIRST AMENDMENT TO
                     CERTIFICATE OF LIMITED PARTNERSHIP AND
                               FIRST AMENDMENT TO
                       AGREEMENT OF LIMITED PARTNERSHIP OF
                        PAINEWEBBER/GEODYNE ENERGY INCOME
                            LIMITED PARTNERSHIP III-A

      The undersigned,  desiring to amend its certificate of limited partnership
pursuant to the Oklahoma  Revised Uniform Limited  Partnership  Act, as amended,
Okla.  Stat.,  tit. 54, Section 301 et seq. (1991) (the "Act"), do hereby state,
and   desiring   to   amend   the   Agreement   of   Limited    Partnership   of
PaineWebber/Geodyne Energy Income Limited Partnership III-A dated as of November
20, 1989, do hereby agree:

      1. The name of the  limited  partnership  is  "Painewebber/Geodyne  Energy
Income Limited Partnership III-A."

The date of  filing  of the  original  Certificate  of  Limited  Partnership  is
November 22, 1989.

      2. The Certificate of Limited  Partnership is hereby revised to change the
name of the Limited Partnership to the following:

             Geodyne Energy Income Limited Partnership III-A

      3. (a) The Certificate of Limited  Partnership is hereby revised to change
the  address of the limited  partnership,  which is the same  address  where the
records of the limited  partnership are kept, to Two West Second Street,  Tulsa,
Oklahoma 74103.

         (b) The Certificate of Limited Partnership is hereby  revised to change
the name and address for the registered agent for  service of process to Geodyne
Production Company, Two West Second Street, Tulsa, OK 74103.

      4. The Certificate of Limited  Partnership is hereby revised to change the
name, mailing address, and business address of the general partner as follows:

                         Geodyne Production Company
                         Two West Second Street
                         Tulsa, OK  74103.

      5. The latest day upon which the  limited  partnership  is to  dissolve is
November 20, 2009.




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      6. The Agreement of Limited  Partnership  is hereby revised to replace the
first sentence of Section 2.1 with the following:

             The Limited  Partnership  shall be conducted under the name Geodyne
             Energy Income Limited Partnership III-A.

      7. The Agreement of Limited  Partnership  is hereby revised to replace the
third and fourth sentences of Section 2.1 with the following:

             The  office  and  principal   place  of  business  of  the  Limited
             Partnership  shall  be c/o  Geodyne  Production  Company,  Two West
             Second  Street,  Tulsa,  Oklahoma  74103.  The agent for service of
             process on the  Limited  Partnership  shall be  Geodyne  Production
             Company, Two West Second Street, Tulsa, OK 74103.

      8. In all other respects,  the Agreement of Limited  Partnership is hereby
ratified and confirmed.

DATED:    February 24, 1993
                                         GENERAL PARTNER:

                                         Geodyne Production Company

                                         By: // Michael E. Luttrell //
                                             -------------------------
                                             Michael E. Luttrell
                                             Executive Vice President

                                         Geodyne Production Company
                                         Attorney-in-fact for any
                                         Substituted Limited Partners

                                         By: // Michael E. Luttrell //
                                             -------------------------
                                             Michael E. Luttrell
                                             Executive Vice President

                                         LIMITED PARTNER:
                                         Geodyne Depositary Company

                                         By: // Michael E. Luttrell //
                                             -------------------------
                                             Michael E. Luttrell
                                             Executive Vice President


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