Tertiary volcanic history of the Sierra del Gallego area, Chihuahua, Mexico

摘要

Mapping of 3,400 km2 in the Sierra del Gallego area, 110 km north of Ciudad Chihuahua, Mexico, has revealed about 1,000 m of volcanic rocks unconformably overlying Lower Cretaceous limestone of the Chihuahua Tectonic Belt. The regional structure is dominated by Basin and Range faults that trend north-northwest and cut all volcanic units.