Geophysical interpretation of subsurface geology, pediment of the San Andres Mountains to the Jornada del Muerto Basin, New Mexico
— Timothy J. Maciejewski and Kate C. Miller

Beginning in 1985, detailed studies of the geology and hydrology in the vicinity of the NASA White Sands Test Facility (WSTF) on the pediment slope of the San Andres Mountains have been undertaken in an effort to define the controls on groundwater movement in the subsurface. Here we present results from a study undertaken in 1995 in which geophysical data sets are integrated with extensive well data in the vicinity of the WSTF to produce new information on the subsurface geology of the region. Our study includes the re-interpretation of 42 mi of shallow seismic reflection data, originally shot in 1987, in conjunction with data from 100 wells that have been drilled since the seismic data were originally acquired. This effort has resulted in a new depth to bedrock structure map that shows that there are two major fault zones trending north northwestsouth- southeast that offset bedrock beneath the study area. Well data and gravity modeling show that Tertiary volcanics have been juxtaposed against Paleozoic sedimentary rocks along the subsurface extension of a fault mapped in outcrop at Hardscrabble Hill and that displacement across this fault is at least 6400 ft.