Geology of the NE 1/4 of the Humphreys quadrangle, Los Angeles County, California

Abstract

The area discussed in this report lies in the southernmost part of the California Coast Ranges, directly northeast of the San Gabriel Mountains and north of the Santa Monica Mountains. The area mapped is the NE 1/4 of the Humphreys Quadrangle. The Humphreys Quadrangle, named after the station of Humphreys on the Southern Pacific Railroad in it's southern part, is located about 40 miles northwest of Los Angeles. It is in latitude 34°30' N and longitude 118°24' W. In the northern section is the southern part of the Sierra Pelona hills, rising to a height of a little over 2700 feet in the Angeles National Forest. The southern section contains the narrow flat valley of the Santa Clara River. The San Andreas fault runs along the south side of Hughes Lake, which is about 15 miles due north. A branch of the San Andreas ends close to the eastern boundary of this area. In the Humphreys Quadrangle, the area studied lies between Bouquet and Mint Canyons, including a portion of Mint Canyon, and also Vasquez and Texas Canyons. By way of Bouquet Canyon, it is approximately 8 miles from the town of Saugus. From Pasadena it may be reached by taking Foothill Blvd. through the San Fernando Valley to Newhall, and then to Saugus. The road to Mojave is taken from Saugus, and either the Mint Canyon or Bouquet Canyon roads lead directly into the area.