The resulting surface features can still be seen today. In 1906 the land at Fort Ross shifted 12.6 feet along a narrow well-defined area above the plate movement.

These sediments were deposited underwater on the Pacific plate forty to sixty million years ago, and have moved from the south about three hundred miles up the California coast.

The fort itself lies on marine sediments to the seaward side of the fault. CaliforniaвЂ™s 1906 earthquake was the sudden result of such motion. On this portion of the fault the movement tends to be in sudden large events, and it is thought that this section of the San Andreas Fault moves significantly only every few hundred years. The fault is the result of the boundaries of the Pacific and North American plates passing by each other. It goes back offshore at Point Arena.Д¬aliforniaвЂ™s major earthquake rift zone, passes through San Francisco and comes ashore two miles south of Fort Ross, then runs north and through the orchard ( see map). From Fort Ross the fault continues overland, forming the valley through which the Gualala River flows. The San Andreas fault ( see map) runs offshore from around Tomales bay in Marin, but comes ashore at Fort Ross. The 1906 earthquake that destroyed San Francisco was centered very near to Fort Ross, and many of the Russian-era buildings were destroyed in that 1906 event. There is a red marker on the road, marking the actual faultlline. If you look carefully at the lay of the land above the fort you can see it, and if you walk up Fort Ross Road, the faultline is clearly visible. All of this is a testament to the incomparable power that these forces of nature can unleash, making the park one of the more accessible destinations at which to witness first-hand the power of plate tectonics.ДЇort Ross sits on the ocean side of The San Andreas fault zone. Even visitors with an untrained eye can see how the sag ponds left behind from the rift caused by the 1906 quake clusters of redwood treetops directly on the fault are still damaged and cracked, and there is a clear offset to the gently sloping coastal hill.ДЄlso in our Fort Ross Visitor Center, we have photos documenting the sizable damage the 1906 quake caused to the historic fort compound, in particular the Fort Ross chapel. The park provides several clearly visible markers of the 1906 temblor, all of which are fairly accessible to the road just uphill from Highway One. This world-famous fault runs along much of the length of the state, skirting on and just offshore CaliforniaвЂ™s coast, and it clearly comes ashore at Ross where its 1906 legacy is still visible.ДЇort Ross is an excellent destination to witness first-hand the powerful effects of plate tectonics and the lasting effect of big earthquakes. The San Andreas fault, CaliforniaвЂ™s major earthquake rift zone, is one natural feature that elicits a strong response from most visitors - many of us have experienced earthquakes and all of us have seen photos of how powerful they can truly be.

San andreas quake