1906 Ground Motion Simulations
Overview
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.
Five second snapshots taken from one of the movies available below. Yellow to red colors indicate regions experiencing damaging shaking. Isolated regions of intense shaking, like the one near Santa Rosa 20 miles from the fault, result from a combination of the amount of slip nearby on the fault, the geologic materials that the seismic waves travel through, and the local geologic conditions.
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 .mov format, which can be viewed using a variety of plugins available for most browsers. These movies are typically 4 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.
