California Rocks: A guide to Geologic Sites in the Golden State

Californians live on the edge . . . of a tectonic plate, that is. In this geologically tenuous location, where a tsunami, earthquake, or volcanic eruption is just another hazard, the rocks and landforms are dynamic too. From erupting geysers and boiling mud pots to collapsing sea arches and crawling landslides, California is a land in motion. In fact, rocks on the west side of the San Andreas Fault have moved northward nearly 200 miles in the last 20 million years