Geology in the SF Bay Area

The public trench across the Hayward fault is open through the end of June! I'm a docent.

San Gregorio Beach, where the San Gregorio fault goes out to sea.

Most of the geology sites I've described in the San Francisco Bay Area are on the San Andreas Fault page.

Until I write up some non-San Andreas related Bay Area trips, here are a few photos:

Hogbacks near Mission and Monument Peaks. I don't know what the history of these hogbacks is, or even what their composition is. I've been completely unable to find a book discussing the geology of this area. Perhaps these are layers of Great Valley Sequence pushing up through the Franciscan Complex?

	Interesting rock near the top of Black Mountain (above Palo Alto).
	Fissure in the hills in Sunol Regional Park. Perhaps related to the Calaveras fault? Note the large landslide area to the left of the fissure.

And here are some links to other sites with useful information:

The San Andreas Fault In The San Francisco Bay Area, California: A Geology Fieldtrip Guidebook To Selected Stops On Public Lands. An excellent collection of tour guides (PDF).

The California Geotour has an excellent collection of online field guides.

USGS On-line Digital Geologic Map Database

Guided Geologic Field Trip of the UCSC Campus

Geology and Natural History of the San Francisco Bay Area, a field trip guidebook (PDF) from the USGS.

Bay Area Geology