<ARTICLE>                           5
<CIK>                               0000860745
<NAME>                              GEODYNE ENERGY INCOME LTD PSHIP III-A

                                 
<PERIOD-TYPE>                       9-MOS
<FISCAL-YEAR-END>                   DEC-31-1999
<PERIOD-START>                      JAN-01-1999
<PERIOD-END>                        SEP-30-1999
<CASH>                                     326,765
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<OTHER-SE>                               2,743,454
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<CGS>                                            0
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