Abstract

The Tucumcari Basin of east-central New Mexico is an asymmetric structural depression that existed as a depositional basin from Desmoinesian (Middle Pennsylvanian) until late Wolfcampian (Early Permian) time. Depth to Precambrian ranges from 6,500 ft in the southern part of the basin to more than 9,000 ft in the complexly faulted northern part of the basin. The Tucumcari Basin is bounded on the west by the Pedernal Uplift, on the north by the Sierra Grande Uplift, and on the northeast by the Bravo Dome. To the east, the Frio Uplift separates the Tucumcari Basin from the Palo Duro Basin of the Texas panhandle.

Source-rock geochemical analyses indicate that strata which contain sufficient total organic carbon to be considered major petroleum source rocks are shales in the Pennsylvanian section and limestones in the San Andres Formation (Permian). The San. Andres appears to be thermally immature throughout most of the basin. The Pennsylvanian section, however, has been matured to the stage of oil generation throughout most of the basin, but is not overmature. The Pennsylvanian contains algal, amorphous and herbaceous kerogens, which may be oil prone. Therefore, it appears that Pennsylvanian shales have generated significant quantities of oil in the Tucumcari Basin.