SA2
Location: Point Reyes (Olema)
Fault: San Andreas
This is one of the most famous San Andreas fault locations where more than 7 meters of right-lateral offset was measured after the great 1906 earthquake. G.K. Gilbert conducted an extensive survey of the 1906 fault ruptures and damage in this area (in Andrew C. Lawson's (1908) report), and took numerous photographs that were published in the report. Some of these photographs can be found at http://mnw.eas.slu.edu/Earthquake_Center/1906EQ/1906thumb.html. Our site is located at the location of the photos shown for the Olema area.
Our alinement array is at the Point Reyes National Seashore Headquarters. The park service has established an official “Earthquake Trail” near the visitor center. A fence showing the large offset due to the 1906 earthquake fault movement is displayed and blue posts are installed to delineate the trace of the 1906 fault rupture, which is now obscurred by time and erosion.
We detect no measurable fault creep at this site.
Reference
A.C. Lawson (1908). The California Earthquake of April 18, 1906, Report of the Sate Earthquake Investigation Commistion, Carnigie Institution of Washington Publication No. 87, volume I, part I, 451 pp.