1. Education

Index Map

Rupture in the 1857 earthquake ran some 300 kilometers from the Parkfield segment to the southern segment. Estimated magnitude was about 8.0. (click full size)
Where it happened
Image based on U.S. Geological Survey fault map
Letter of W. E. Greenwell, U.S. Coast Survey, February 24, 1857:

"Just back of my camp was the dry bed of a stream, where in heavy rains water had at one time run; in this bed two weeks before I had sunk a well some 20 feet hoping to find water, but at that depth the earth was so dry I gave it up as fruitless. Two days after the first or heavy shock a little stream of muddy water was running by my camp which continued to increase each day, until when we moved was quite a little rivulet: no doubt the result of some new fissure in the mountain."

©2013 About.com. All rights reserved.