static stress changes-- coulomb. key concepts: source faults receiver faults optimally oriented...
Post on 22-Dec-2015
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Key concepts:•Source faults•Receiver faults•Optimally oriented faults•Assume receiver faults are close to failure•Triggering lag time is a problem
Change of coulomb stress on faults of specified orientation
Can change spatiallyRemote:
Induced:
Total:
Can change spatially
1992 M=7.3 Landers shock increases stress
at Big Bear
LosAngeles
BigBear
Landers
First 3 hr of Landers
aftershocks
plottedfrom Stein (Nature, 2003)
1992 M=7.3 Landers shock promotes the M=6.5 Big
Bear shock 3 hr later
LosAngeles
BigBear
Landers
First 3 hr of Landers
aftershocks
plottedfrom Stein (Nature, 2003)
…and promotes the M=7.1 Hector Mine shock 7 yr later
LosAngeles
Hector Mine
First 7 yr of
aftershocksplotted
from Stein (Nature, 2003)
fromHarris & Simpson
(1998) and Parsons(2003)
Bay area faultsmay have
fallen undera stress shadow
in 1906
http://quake.usgs.gov/research/deformation/modeling/animations/index.html