<ARTICLE> 5 <CIK> 0000860745 <NAME> GEODYNE ENERGY INCOME LTD PARTNERSHIP III-A <PERIOD-TYPE> 9-mos <FISCAL-YEAR-END> DEC-31-2000 <PERIOD-START> JAN-01-2000 <PERIOD-END> SEP-30-2000 <CASH> 679,491 <SECURITIES> 0 <RECEIVABLES> 633,380 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 1,312,871 <PP&E> 16,985,950 <DEPRECIATION> 15,505,051 <TOTAL-ASSETS> 3,073,421 <CURRENT-LIABILITIES> 81,087 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 0 <OTHER-SE> 2,942,282 <TOTAL-LIABILITY-AND-EQUITY> 3,073,421 <SALES> 2,651,107 <TOTAL-REVENUES> 2,675,055 <CGS> 0 <TOTAL-COSTS> 1,235,911 <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 0 <INCOME-PRETAX> 1,439,144 <INCOME-TAX> 0 <INCOME-CONTINUING> 1,439,144 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 1,439,144 <EPS-BASIC> 4.81 <EPS-DILUTED> 0