Preliminary report on the stratigraphy and structure of Pennsylvanian and Lower Permian strata, Tucumcari Basin
— Ronald F. Broadhead and William E. King

The Tucumcari basin of Guadalupe, Quay, Curry, De Baca and San Miguel Counties, northeastern and east-central New Mexico, is Middle Pennsylvanian to Early Permian in age. Little evidence of this basin can be garnered from surface geologic studies where gentle surface structures only vaguely mimic the large-scale, deeper, basinal structures. The Tucumcari basin (Fig. 1) is bounded on the north and west by the late Paleozoic Sierra Grande and Pedernal uplifts. Faults that bound the basin are chiefly Middle Pennsylvanian to Early Permian in age and some have vertical displacements of several thousand feet. Upper Pennsylvanian and Lower Permian strata thicken dramatically across these faults. Furthermore, the faults were a major controlling factor of basin geometry, and, because of this, they exhibit a strong control on sedimentary facies.

The Tucumcari basin has been the site of sporadic exploration and drilling for oil and gas during the last 50 years. Until now, commercial quantities of oil and gas have not been produced from the basin, but exploratory wells have encountered shows of oil and gas in Pennsylvanian, Permian and Triassic strata. Increased exploratory activity in the last five years has resulted in the discovery of oil and gas in Pennsylvanian rocks by Trans-Pecos Resources (now Gila Exploration) in  Guadalupe County (Fig. 1, letter A) and by Yates Petroleum Corporation in western Quay County (Fig. 1, letter B). At the time this report was written, Trans-Pecos had initiated a gas-injection, enhanced, oil-recovery project to produce oil from their discovery.

This study was undertaken in order to investigate the late Paleozoic stratigraphy and structure of the Tucumcari basin. Comprehension of that stratigraphy and structure is crucial to understanding the distribution of petroleum source and reservoir facies within the basin. This report is preliminary and reflects only the initial stages of our study.