The Earthquake Trail is a short, fully paved and handicap accessible interpretive loop that provides visitors with information on the unique geological forces that shape Point Reyes and Northern California. San Francisco is famous for being prone to earthquakes and there is good reason. But to understand why, one must first learn a little about plate tectonics.

Plate Tectonics

While the core of our earth is solid, the outer core is actually molten - or liquid. Resting above the outer core and lower mantle are fourteen major tectonic plates, which ultimately comprise the solid surface of the earth.

These major tectonic plates include the Pacific and North American plates, which ride the molten outer core of the earth, colliding with each other to form continents, mountain ranges and deep-sea chasms. Each plate collision and subsequent grinding can produce fantastic geologic consequences such as earthquakes, tsunamis or the release of underground oil and gas. The incurring fracture, which occurs upon two plates colliding, is called a fault line.

San Andreas Fault

Riding the northern border of Point Reyes National Seashore and cutting through the floor of Tomales Bay is the San Andreas Fault. The fault itself is infamous - yet only recently has it become less of a geological mystery to scientists.

The San Andreas fault system is now known to be directly responsible for all the major earthquakes in the San Francisco Bay Area and is actually a series of multiple faults, which extend 780 miles south through California. Included in this complex system are the San Andreas, Hayward and Calaveras faults - all which enable tectonic movement between the Pacific and North American plates.