BROADHEAD, RONALD F.
New Mexico Bureau of Mines and Mineral Resources, a Division of New Mexico Tech, Socorro, New Mexico

Abstract: Underdeveloped Oil Fields - Upper Pennsylvanian and Lower Wolfcampian Carbonates of Southeast New Mexico

Carbonate reservoirs in the Cisco and Canyon (Upper Pennsylvanian) and Lower Wolfcampian (Permian) sections in the Permian Basin of southeast New Mexico are significant reservoirs for oil and gas. The 400 fields that have produced from these reservoirs have yielded a cumulative production of 490 MMBO and 3.2 TCF gas. Sixteen fields, which were underdeveloped at some stage in their history, were identified.

Although initially underdeveloped, subsequent redevelopment added significantly to reserves and production. For the 16 fields studied, redevelopment accounted for 65% of developed reserves. Redevelopment accounted for more than 95% of total reserves at Dagger Draw, which turned this seemingly insignificant field into the most productive field in New Mexico, with 9.8 MMBO production in 1996. Redevelopment of Dagger Draw has reversed the production decline in southeast New Mexico.

Redevelopment in these fields was generally in undrilled portions of the fields, and not in bypassed pay zones. The fields are formed by stratigraphic traps, but were initially thought to be structural traps, and were developed as such. Because initial development was on structure, and off structure areas were undrilled, most reserves remained unproduced until redevelopment. Because 91% of the Upper Pennsylvanian and Lower Wolfcampian fields have less than 10 producing wells, and have been developed primarily on structures, significant reserves may remain undeveloped in existing fields.

AAPG Search and Discovery Article #90918©1999 AAPG Southwest Section Meeting, Abilene, Texas