Sixth Amendment to
                       Agreement of Limited Partnership of
                Geodyne Energy Income Limited Partnership III-D

     This Sixth Amendment to Agreement of Limited  Partnership of Geodyne Energy
Income  Limited  Partnership  III-D (the  "Partnership")  is entered into by and
between  Geodyne  Resources,  Inc.  ("Resources"),  a Delaware  corporation,  as
successor General Partner, Geodyne Depositary Company ("Depositary"), a Delaware
corporation,  as the  Limited  Partner,  and all  Substituted  Limited  Partners
admitted to the Partnership.

     WHEREAS,  on September 5, 1990, Geodyne Production Company  ("Production"),
as General  Partner  and  Depositary  executed  and  entered  into that  certain
Agreement of Limited Partnership of the Partnership (the "Agreement"); and

     WHEREAS,  on February 25, 1993,  Production  executed and entered into that
certain  First  Amendment  to the  Agreement of Limited  Partnership  whereby it
changed (i) the name of the Partnership from "PaineWebber/Geodyne  Energy Income
Partnership III-D" to "Geodyne Energy Income Limited  Partnership  III-D",  (ii)
the address of the  Partnership's  principal  place of  business,  and (iii) the
address for the Partnership's agent for service of process; and

     WHEREAS,  on August 4, 1993,  Production  executed  and  entered  into that
certain Second Amendment to the Agreement of Limited Partnership in order to (i)
expedite the method of accepting  transfers of Unit  Holders' (as defined in the
Agreement)  Units in the  Partnership  and (ii) provide for an optional right of
repurchase/redemption which may be exercised by the Unit Holders; and

     WHEREAS,  on August 31,  1995,  Production  executed  and entered into that
certain Third Amendment to the Agreement  whereby it amended certain  provisions
to allow transfers of Units facilitated through a matching service to the extent
that such transfers  otherwise  comply with Internal  Revenue  Service  transfer
regulations  applicable  to  non-permitted  transfers  for  non-publicly  traded
limited partnerships; and

     WHEREAS, on June 30, 1996,  Production merged into Geodyne Resources,  Inc.
("Resources"); and

     WHEREAS, on July 1, 1996, Resources, as successor via merger to Production,
executed and entered into, as General Partner,  that certain Fourth Amendment to
the Agreement of Limited Partnership whereby it amended the Agreement to provide
that  Resources,  as successor via merger to Geodyne,  is the General Partner of
the Partnership; and

     WHEREAS,  on August 23,  2000,  Resources  executed  and entered  into that
certain Fifth Amendment to the Agreement whereby the term of the partnership was
extended for an additional two years, until September 5, 2002, and

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     WHEREAS,  Section 2.3 of the Agreement  provides that the Partnership shall
continue  in full  force and effect for a period of ten (10) years from the date
of its  Activation  (as  defined in the  Agreement),  provided  that the General
Partner  may extend the term of the  Partnership  for up to four  periods of two
years each if it believes  each such  extension is in the best  interests of the
Unit Holders or until  dissolution  prior thereto  pursuant to the provisions of
the Agreement, and

     WHEREAS, Resources as General Partner has elected to extend the life of the
Partnership an additional two years.

     NOW,  THEREFORE,   in  consideration  of  the  covenants,   conditions  and
agreements herein contained, the parties hereto hereby agree as follows:

      Section 2.3. is hereby amended and restated as follows:

               The  Partnership   shall  continue  in  force  and  effect  until
          September 5, 2004,  provided  that the General  Partner may extend the
          term of the  Partnership  for up to three periods of two years each if
          it  believes  such  extension  is in the  best  interests  of the Unit
          Holders, or until dissolution prior thereto pursuant to the provisions
          hereof.

      IN WITNESS WHEREOF, the parties hereto have hereunto set their hands as of
this 20th day of August, 2002.

                                    GEODYNE RESOURCES, INC.,
                                    as General Partner

                                    By:   //S// Dennis R. Neill
                                          ---------------------
                                          Dennis R. Neill
                                          President

                                    GEODYNE DEPOSITARY COMPANY,
                                    as the Limited Partner

                                    By:   //s//Dennis R. Neill
                                          ---------------------
                                          Dennis R. Neill
                                          President

                                    GEODYNE RESOURCES, INC.
                                    as Attorney-in-Fact for all
                                    Substituted Limited Partners

                                    By:   //s//Dennis R. Neill
                                          ---------------------
                                          Dennis R. Neill
                                          President

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