A cooperative project with the California Geological Survey

Introduction

The San Francisco Bay region is home to 7 million people whose lives are intertwined with some of the most complex and active geology in the world. With heightened public awareness about earthquake hazards on the 100th anniversary of the 1906 San Francisco earthquake, the U.S. Geological Survey, in cooperation with the California Geological Survey, is releasing three new maps of the San Francisco Bay Area designed to provide a new look at the geologic history and hazards of the region:

(Note: The following maps below require the Shockwave player to view. You can download the Shockwave player here. )

Geologic Map
Shows the distribution of geologic materials and geologic structures that are visible at the Earth's surface, with information about geologic materials, geologic time, fossils, and the geologic history of the San Francisco Bay region.

Quaternary-Active Fault Map
Shows the distribution of faults in the San Francisco Bay region most likely to generate future earthquakes, with information about active faults and how geologists find them and study them.

Liquefaction Susceptibility Map
Shows the distribution of rock and sediment having different vulnerabilities to liquefaction when shaken by earthquakes, together with explanation of the process and examples of its effects.

This Web site provides enhanced access to these maps, including additional information, images, downloads, and links.