Circular 63 — A Geologic notes on the Delaware Basin

By L. Haigler, 1962, 14 pages.

The Delaware basin of New Mexico lies in Eddy and Lea counties, New Mexico, and contains about the northern one fourth of the total area of the Delaware basin. It is a structural depression bordered on the east by the Central Basin Platform and on the west by the Guadalupe Mountains and has its inception in either Late Pennsylvanian or Early Permian time. For the purpose of this report the limits of the Bone Spring Limestone are considered to be the limits of the Delaware Basin.

Formations ranging in age from Ordovician up to the Ochoa Series of the Permian are of marine origin, while deposits ranging in age from the Ochoa Series of the Permian through the Quaternary are evaporites or red beds of continental origin. The maximum thickness of formations of Permian age is approximately 12,000 feet. None of the wells examined penetrated formations that are Precambrian in age, and the problem of locating the contact between formations of Permian and Pennsylvanian ages is still unsolved. Examination of well cuttings and electric and radioactivity logs indicated that the following geologic horizons could be correlated for considerable distances across the Delaware basin:

The El Paso Limestone where the Simpson Group equivalent is present, the Simpson Group equivalent, the formations of Siluian(?) and Devonian(?) ages, the Woodford Shale equivalent, the limestone of Mississippian age, the shale of Mississippian age, the Strawn Group of Pennsylvanian age, the Hueco Limestone where the third Bone Spring sand of local usage is present, the Bone Spring Limestone, top of the Delaware Mountain Group, and the Rustler Formation. Other correlations within the Delaware basin could be made, but they should be considered less reliable or made only over shorter distances.