thumbnail

Basin structure beneath the Santa Rosa Plain, Northern California: Implications for damage caused by the 1969 Santa Rosa and 1906 San Francisco earthquakes

Bulletin of the Seismological Society of America

By:
, , , , , , and
DOI: 10.1785/0120060269

Links

Abstract

Regional gravity data in the northern San Francisco Bay region reflect a complex basin configuration beneath the Santa Rosa plain that likely contributed to the significant damage to the city of Santa Rosa caused by the 1969 M 5.6, 5.7 Santa Rosa earthquakes and the 1906 M 7.9 San Francisco earthquake. Inversion of these data indicates that the Santa Rosa plain is underlain by two sedimentary basins about 2 km deep separated by the Trenton Ridge, a shallow west-northwest-striking bedrock ridge west of Santa Rosa. The city of Santa Rosa is situated above the 2- km-wide protruding northeast corner of the southern basin where damage from both the 1969 and 1906 earthquakes was concentrated. Ground-motion simulations of the 1969 and 1906 earthquakes, two events with opposing azimuths, using the gravity- defined basin surface, show enhanced ground motions along the northeastern edge of this corner, suggesting that basin-edge effects contributed to the concentration of shaking damage in this area in the past and may also contribute to strong shaking during future earthquakes.

Study Area

Additional publication details

Publication type:
Article
Publication Subtype:
Journal Article
Title:
Basin structure beneath the Santa Rosa Plain, Northern California: Implications for damage caused by the 1969 Santa Rosa and 1906 San Francisco earthquakes
Series title:
Bulletin of the Seismological Society of America
DOI:
10.1785/0120060269
Volume:
97
Issue:
5
Year Published:
2007
Language:
English
Publisher:
Seismological Society of America
Publisher location:
Stanford
Description:
9 p.
Larger Work Type:
Article
Larger Work Subtype:
Journal Article
Larger Work Title:
Bulletin of the Seismological Society of America
First page:
1449
Last page:
1457
Country:
United States
State:
California
Other Geospatial:
Santa Rosa Plain
Online Only (Y/N):
N
Additional Online Files (Y/N):
N