Evidence for aseismic deformation in the western Transverse Ranges, Southern California; implications for seismic risk assessment

Recent studies in southern California suggest that long-term deformation rates are far in excess of that which can be accounted for by historical seismicity, and thus, a deficit of moderate and/or large earthquakes exists in southern California. Although possible, this conclusion is not unique becau...

Full description

Saved in:
Bibliographic Details
Published in:Geology (Boulder) 1998-03, Vol.26 (3), p.271-274
Main Authors: Duebendorfer, Ernest M, Vermilye, Jan, Geiser, Peter A, Davis, Thomas L
Format: Article
Language:English
Subjects:
bedding
California
Cenozoic
cleavage
deformation
Earthquakes
Environmental geology
Eocene
faults
field studies
foliation
geologic hazards
Geology
Juncal Formation
Los Angeles County California
Matilija Formation
microstructure
Miocene
Monterey Formation
Neogene
Paleogene
planar bedding structures
Plate tectonics
pressure solution
risk assessment
San Cayetano Fault
San Gabriel Fault
sedimentary rocks
sedimentary structures
seismic risk
Seismology
Southern California
strain
structural analysis
Structural geology
Tertiary
Transverse Ranges
United States
Ventura Basin
Ventura County California
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Recent studies in southern California suggest that long-term deformation rates are far in excess of that which can be accounted for by historical seismicity, and thus, a deficit of moderate and/or large earthquakes exists in southern California. Although possible, this conclusion is not unique because aseismic deformation may have contributed to bulk regional strain. We examined Cretaceous to Pleistocene sedimentary rocks exposed in the Ventura basin along four cross-strike traverses to evaluate the possibility that aseismic deformation contributed to regional shortening. Our field and microstructural investigations suggest that aseismic deformational mechanisms, particularly pressure solution, contributed significantly to permanent shortening strain during the late Neogene and that the proposed seismic deficiency may be overestimated.
ISSN:0091-7613
1943-2682
DOI:10.1130/0091-7613(1998)026<0271:EFADIT>2.3.CO;2