GEOPHYSICAL TECHNIQUES IN THE POTRILLO VOLCANIC FIELD

The Potrillo Volcanic Field (PVF) is a unique geological site located in Doña Ana County in the southernmost part of New Mexico, and part of northern Chihuahua, Mexico. This large field consists of several hundred lava flows, cinder cones, and maar craters that range in age from 1.2 million years to only 16,000 years old. Most of the rocks are basalts.

The purpose of this research is to use geophysical techniques (e.g., gravity and magnetics) to more precisely map the Mt. Riley, East Potrillo and other Quaternary faults in the study area and correlate these faults with the creation of the Potrillo Maar,a feature that straddles the U.S.-Mexico border.

A previous study at Potrillo Maar determined the extent of the maar-diatreme and the thickness of the basalt in the area by using gravity and magnetic surveys. It also provided a better understanding of the shallower structures near the diatreme, Including a basaltic feeder dike. The main dike is located in the center of the maar crater where three scoria cones are exposed at the surface. Other smaller dikes are also located within the diatreme.