The San Francisco Bay Area's crazy quilt-pattern of rock formations -- shaped by earthquakes -- are the key to understanding the region's landscapes. From ice-age dune sand in San Francisco to recently subsided land in the Santa Clara Valley or the veritable maze of earthquake faults in the East Bay, the geology is a fascinating blueprint of the region's natural history.

From the Inside Out

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Workers digging the new fourth bore of the Caldecott Tunnel are getting a once-in-a-lifetime view of one of the defining features of the East Bay: the range of hills that runs from San Pablo Bay south to Fremont. By visiting just a few accessible sites aboveground, you can find clues that tell the story of how these hills rose from their humble origins as deep ocean sediments and volcanic flows to the iconic fault-riddled hillsides of today.

Got Quakes on the Mind?

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With a handful of very noticeable earthquakes jolting the East Bay, we’re getting a lot of questions about quakes — do small ones release strain? Or foretell the Big One? We get the word from one of UC Berkeley’s top seismologists.

A Life in Geologic Time

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In the 1970s, mother and peace activist Doris Sloan was working a nonprofit desk job in a basement office in San Francisco when she got into a UC Extension Sierra field class and fell in love with geology. The rest, as they say, is history. Over the subsequent three decades spent teaching, writing, and leading field trips, Sloan has done more than anyone to make the complex geology of California and the Bay Area comprehensible and fun for those of us without PhDs.

School of Rock

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Berkeley native Erik Vance first encountered the rocks of the East Bay hills as a teenager looking for excitement. For a century, geologists at UC Berkeley have used them to teach geologic mapping, in the process unraveling the complex geology of our hills. And for decades pioneering rock climbers learned techniques here that they took with them to the Sierra and beyond.