To better understand the distribution of shaking and damage that accompanied the great 1906 earthquake, seismologists have constructed new computer models to recreate the ground motions. The simulations show how ground moved on the two sides of the San Andreas fault and how seismic waves radiated away from the fault to produce the shaking. The earthquake, which began 2 miles offshore from the City of San Francisco, ultimately grew to cause shaking and damage along more than 300 miles of the San Andreas Fault.
The movies and snapshots available here portray the shaking over a 155 mile by 70 mile area covering the San Francisco Bay region. They are offered in .mp4 format, which can be viewed using most browsers. These movies are typically 10 MB or more in size, and are best downloaded using a high speed internet connection. Snapshots from one movie are also offered as an alternative for those with slower modem connections.
Map Views of Ground Shaking
Map-view snapshots and movies show the seismic waves propagating outward from the fault as the rupture expands north and south from the epicenter, which lies offshore from San Francisco. The colors and shading indicate the maximum shaking intensity at each location and the current shaking at the time noted in seconds on each movie frame.
Closeup Views of Ground Shaking
These closeup images provide an oblique perspective view of the shaking at a particular location. Each image looks toward San Francisco and the epicenter, so you will see the seismic waves traveling toward you. The deformation in the ground surface has been exaggerated 1000 times to make it visible. Thus, one mile of deformation represents a little more than 5 feet of actual ground movement. Click on any of the locations on the map below or use the links under the map to view the movie of shaking at that location.