Abstract

The Atlas of Major Texas Gas Reservoirs (Kosters and others, 1989) grouped Permian Basin reservoirs with 1986 cumulative gas production greater than 10 billion ft³ into 18 plays. Production from these major Permian Basin gas fields totaled 42.3 trillion ft³ through 1986. To expand the data base to include smaller and newer fields, we identified 143 additional reservoirs having cumulative production greater than 6 billion ft³ through 1998. The reservoirs were assigned to plays, and the play boundaries were modified to include the additional reservoirs.

Cumulative production from these 143 reservoirs is 2.2 trillion ft³. Production data include both nonassociated gas and associated gas-well gas but not associated casinghead gas. No adjustments were made for gas cycling. The Upper Pennsylvanian and Lower Permian Slope and Basinal Sandstone (479 billion ft³) and the Strawn Group Shallow-Marine Carbonate (383 billion ft³) plays account for the greatest production increases. The Upper Pennsylvanian and Lower Permian Slope and Basinal Sandstone play (30 reservoirs), Siluro-Devonian Carbonate-Deep Delaware and Val Verde Basins play (21 reservoirs), Strawn Group Shallow-Marine Carbonate play (18 reservoirs), Ellenburger Fractured Dolostone play (14 reservoirs), and Atoka Group Limestone and Sandstone play (12 reservoirs) contain the greatest number of additional reservoirs.