GEOLOGY AND SOILS

For studies of geophysical processes, the site offers many interesting features to geologists, geomorphologists studying hillslope processes, and hydrologists, Interestingly, the University of California established in 1887, at Berkeley and at Mt. Hamilton, the first seismographic stations in the Western Hemisphere on a permanent basis. These stations were in the charge of the Departments of Astronomy, Civil Engineering, and Geology.

The Mt. Hamilton area is a part of the Diablo Range, which extends from the Carquinez Straits south 170 miles to Coalinga. Bedrock in this range includes ancient marine sedimentary rocks and might provide interesting opportunities for paleomicrobial research.

The Arroyo Aguague fault, a branch of the Calaveras fault, runs almost directly up the Arroyo Aguague. Many minor faults branch out through the ranch, probably forming the many intermittent drainages. Due to the many faults, perennial springs are found throughout most of the property. Much of the western portion of the ranch is underlain by large chert formations, which are exposed on many parts of the ranch. Much of what underlies the ridges above the Arroyo Hondo is unstable mélange, and the area is punctuated with many young landslides. By contrast, the west side’s many slides are quite old (Earth Sciences Associates, 1979.) Blue Oak Ranch Reserve appears to be very well suited to research by geomorphologists studying hillslope processes.

Soils are of the Los Gatos-Gaviota complex, derived from hard sandstone and shale from the Franciscan formation and younger (Miocene age) marine sediments. Rock outcrops and unstable talus slopes are common.

Posted on March 7, 2014 06:41 AM by infomgr