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.

Voice of the Volcano

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We all know that the East Bay hills are ripe for an earthquake, but volcanoes? Don’t look for lava in the headlines anytime soon, but there is a place in Oakland where an ancient volcano has laid bare a tale of fiery eruptions, long-extinct ecosystems, and the massive movements of tectonic plates. Many people go to Sibley Regional Preserve for the views of Mount Diablo or the quirky labyrinths at the bottoms of old quarry pits. But look closely at the trailside rocks, and you’ll see lava flows and a volcano turned on its side!

Down to the Sea Again

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Daly City’s cliffs hold tales of ancient seas and volcanic eruptions. But don’t count on them to stand still under your feet, or your home.

Going Overboard

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In 1985, when Jane and Ray Pittsinger rented a house at 548 Esplanade Avenue in Pacifica, they had a 30-foot-deep backyard that fronted on the cliffs, a staircase down to the beach, and the most amazing views of the Pacific … Read more

Taking Refuge

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At this small, sandy National Wildlife Refuge on the industrial outskirts of Antioch, you’ll find great views of the San Joaquin River, and rare plants and insects that don’t exist anywhere else.

Serpentine Splendor

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Tucked into less than a square mile of land next to a freeway, the Peninsula’s Edgewood Park is a showcase for stunning wildflower diversity, all the result of our region’s unique geology.

Book Review: A Dangerous Place

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by Marc Reisner, Pantheon Books, 2003, 181 pages, $22.   Don’t let the hyperinflated housing market fool you. The Bay Area is sit-uated atop some of the most seismically unappealing real estate in the world. In fact, the nine-county region … Read more

Peninsula Treasure

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This former home of Italian winemakers, a ’70s commune, and a recluse named Indian Joe saw its share of history before being acquired by the Midpeninsula Regional Open Space District. Now it boasts its fair share of easily accessible geological anomalies, diverse wildlife, and spectacular views.

The Fire Down Below

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A shower of magma-heated liquid and steam makes for more than just a pretty Calistoga postcard. It’s a 30-million-year-old lesson in California’s dynamic underground history of sliding plates, volcanic eruptions, and molten rock.

Postcards from Pescadero

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True, there was no e-mail, snail mail, or even Pony Express, but somehow postcards from intrepid explorers of the San Mateo coast in days of yore have reached our mailbox. Take a unique trip through time and discover how the beach and marsh at Pescadero came to be the treasures we love to visit today.