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.

The Rock in the Redwoods

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Take a hike to a scene of otherworldly geology, hidden away in this Peninsula preserve’s forests of tanoak, Douglas-fir, and second-growth redwood.

Tafoni Around the Bay

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The tafoni weathering formation featured at El Corte de Madera Creek Preserve is a particularly accessible example of an uncommon phenomenon, but there are several other places to see tafoni in the Bay Area. At Castle Rock State Park west … Read more

Carquinez Breakthrough

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The open hills along the Carquinez Strait are home to working ranches and open space preserves that are meeting places for native species from both the coast and the Central Valley. Today’s quiet pastoral landscape makes it hard to envision the violent formative flood that may have cut this critical waterway between the Bay and the Central Valley some half a million years ago.

Beachfront Property

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San Francisco’s Fort Funston is perhaps best known for dogs and hang gliders, but its cliffs also host a thriving coastal bank swallow colony.

Betting on Point Molate

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With stunning views of the Bay and Marin, Richmond’s Point Molate has seen a lot of changes: It’s been a shrimp camp, a huge winery, and a Navy fuel depot. Now the site of a controversial casino proposal, this modest point of land is home to diverse wildlife and some of the East Bay’s last native coastal prairie.

Earthquake Resources

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Plate Tectonics And Earthquakes National Earthquake Information Center USGS website providing current data on earthquakes worldwide. USGS Earthquake Hazards Program-Northern California Website providing general and latest quake information, hazard maps, sources of preparedness information, synthesis of current research, and resources. … Read more

In the Fault Zone

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On April 18, 1906, a massive earthquake centered just west of San Francisco ruptured the earth from Humboldt to San Juan Bautista. While the more dramatic traces of this 7.8 temblor may be hard to find one hundred years later, the tectonic forces that moved the earth that day are still relentlessly shaping our young and active landscape, carrying us towards another cataclysm in the near future.

On The Move

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All of the familiar landforms we see here in the Bay Area—ridges, cliffs, lakes, and even San Francisco Bay itself—are products of the same titanic encounters between tectonic plates that produce our frequent quakes. Through a geologist’s trained eye, we learn to interpret the signs these forces have left on the land around us.