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Multiscale Dynamics of Aseismic Slip on Central San Andreas Fault
Author(s) -
Khoshmanesh M.,
Shirzaei M.
Publication year - 2018
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1002/2018gl077017
Subject(s) - creep , geology , san andreas fault , slip (aerodynamics) , seismology , interferometric synthetic aperture radar , induced seismicity , fault (geology) , synthetic aperture radar , materials science , remote sensing , physics , composite material , thermodynamics
Understanding the evolution of aseismic slip enables constraining the fault's seismic budget and provides insight into dynamics of creep. Inverting the time series of surface deformation measured along the Central San Andreas Fault obtained from interferometric synthetic aperture radar in combination with measurements of repeating earthquakes, we constrain the spatiotemporal distribution of creep during 1992–2010. We identify a new class of intermediate‐term creep rate variations that evolve over decadal scale, releasing stress on the accelerating zone and loading adjacent decelerating patches. We further show that in short‐term (<2 year period), creep avalanches, that is, isolated clusters of accelerated aseismic slip with velocities exceeding the long‐term rate, govern the dynamics of creep. The statistical properties of these avalanches suggest existence of elevated pore pressure in the fault zone, consistent with laboratory experiments.