EXTRA : Biggest California Quakes; Worst Was in S.F. in 1906

Here is a list of major earthquakes, in order of magnitude, that have struck California this century.

Today’s earthquake near Los Angeles registered an estimated 6.0 on the Richter scale, a quake capable of causing severe damage. An earthquake measuring 7.0 on the Richter scale is a major quake, capable of widespread heavy damage; 8 is a great quake, capable of tremendous damage.

The Richter scale is a measure of ground motion as recorded on seismographs. Every increase of one number means a tenfold increase in magnitude. Thus a reading of 7.5 reflects an earthquake 10 times stronger than one of 6.5.

1906--San Francisco, 8.3.

1952--Tehachapi-Bakersfield, 7.8.

1927--Offshore San Luis Obispo, 7.7.

1923--North Coast, 7.2.

1980--Eureka, 7.0.

1940--Imperial Valley, 6.7.

1911--Coyote, 6.6.

1980--Mammoth Lakes, four quakes, 6.0 to 6.6.

1983--Coalinga, 6.5.

1979--Imperial Valley, 6.4.

1968--Anza-Borrego Mountains, 6.4.

1971--Sylmar, 6.4.

1933--Long Beach, 6.3.

1925--Santa Barbara, 6.3.

1984--Morgan Hill, 6.2.

1986--Palm Springs, 6.0.

Figures for the southern part of the state were provided by Riley Geary, a seismologist at Caltech, and for the northern part by the U.S. Geological Survey.