CERTIFICATION
                       PURSUANT TO 18 U.S.C. SECTION 1350,
                    AS ADOPTED PURSUANT TO SECTION 906 OF THE
                           SARBANES-OXLEY ACT OF 2002


      The undersigned  hereby  certify,  pursuant to 18 U.S.C.  Section 1350, as
adopted pursuant to Section 906 of the  Sarbanes-Oxley Act of 2002, that, to the
undersigned's  best knowledge and belief,  the Quarterly Report on Form 10-Q for
the Geodyne Energy Income Limited  Partnership  III-A  ("Issuer") for the period
ending  September 30, 2002 as filed with the Securities and Exchange  Commission
on the date hereof (the "Report"):

      (a)   fully complies with the requirements of section 13(a) or 15(d) of
            the Securities Exchange Act of 1934; and
      (b)   the  information  contained in the Report  fairly  presents,  in all
            material respects, the financial condition and results of operations
            of the Issuer.

      Dated this 8th day of January, 2003.

                                    GEODYNE ENERGY INCOME LIMITED
                                    PARTNERSHIP III-A
                                   ("Issuer")

                                    //s// Dennis R. Neill
                                    -----------------------------------
                                    Dennis R. Neill
                                    President (Chief Executive Officer)

                                    //s// Craig D. Loseke
                                    -----------------------------------
                                    Craig D. Loseke
                                    Chief Accounting Officer
                                    (Chief Financial Officer)