Abstract

The Sin Nombre area of east-central New Mexico sits astride the boundary between the Permian Basin to the south and the Tucumcari Basin to the north. It covers an area of approximately 7000 mi² in DeBaca, northern Roosevelt, southern Curry, northern Chaves, northeastern Lincoln, and southwestern Guadalupe Counties, New Mexico. Approximately 100 BCF gas and 6 million bbls oil have been produced from 17 oil and gas pools in the southeast and south-central portions of Sin Nombre. Low-permeability sandstones of the Abo Formation (Permian) have yielded most of the gas but Pennsylvanian limestones and Silurian and Ordovician dolostones are also important gas reservoirs. Silurian dolostones and Pennsylvanian limestones have been the primary oil reservoirs.

Significant potential remains for additional, undiscovered and unproduced oil and gas resources. Marginal gas discoveries in the central part of the Sin Nombre area may have remained unproduced because of a paucity of pipelines along the northwestern fringe of the Permian Basin. Although drilling density is low, oil and gas shows encountered by unsuccessful exploratory wells indicate that large portions of the area have been at least partially charged by hydrocarbons. Hydrocarbons in the southern part of the Sin Nombre area would most likely have migrated north from source rocks in the Permian Basin. Hydrocarbons in the northern part of the Sin Nombre area would have migrated southward from source rocks in the Tucumcari Basin. Opportunities for traps include localized, basement-controlled structural highs throughout the stratigraphic section as well as northward pinchouts of lower Paleozoic reservoirs and truncation of Paleozoic strata against major east-west trending faults in the subsurface.