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Contrasts in compliant fault zone properties inferred from geodetic measurements in the San Francisco Bay area

Journal Article · · Journal of Geophysical Research. Solid Earth
DOI:https://doi.org/10.1002/2016JB013243· OSTI ID:1480732
 [1];  [1]
  1. Univ. of California, Berkeley, CA (United States). Dept. of Earth and Planetary Sciences
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In crustal fault zones, regions of damaged rock characterized by reduced elastic shear modulus can influence patterns of near-field interseismic deformation. In order to study these compliant fault zones (CFZs) and how they might develop over the lifetimes of faults, we compare two fault segments with contrasting fault age and lithology along the San Andreas Fault in the San Francisco Bay Area. New geodetic measurements of the interseismic velocity fields at each location are used to constrain fault zone parameters through a Markov chain Monte Carlo method. At Black Mountain, in the Santa Cruz Mountains of the San Francisco Peninsula, we do not find evidence for a compliant fault zone; instead, we find that the geodetic data are more consistent with a model of a single fault in a homogeneous elastic half-space. At Lake San Andreas, a younger fault segment 35 km farther north, we find evidence for a compliant fault zone about 3.4 +1.1/-1.4 km wide, containing a shear modulus of about 40% of the shear modulus of the surrounding rock. We also find that the best fitting CFZ model at this location, unlike the best fitting homogeneous half-space model, has a locking depth that agrees well with the observed depth of microseismicity. Based on differences in fault age, cumulative displacement, and lithology between Black Mountain and Lake San Andreas, we infer that lithology plays an important and, in this case, perhaps a dominant role in the accumulation of fault zone damage structures and the development of CFZs over the lifetime of a fault.
Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Grant/Contract Number:
AC02-05CH11231
OSTI ID:
1480732
Journal Information:
Journal of Geophysical Research. Solid Earth, Journal Name: Journal of Geophysical Research. Solid Earth Journal Issue: 9 Vol. 121; ISSN 2169-9313
Publisher:
American Geophysical UnionCopyright Statement
Country of Publication:
United States
Language:
English

References (41)

Localized and distributed creep along the southern San Andreas Fault journal October 2014
Geodetic exploration of strain along the El Pilar Fault in northeastern Venezuela journal March 2015
A permeability and compliance contrast measured hydrogeologically on the San Andreas Fault: HYDROGEOLOGIC ARCHITECTURE OF FAULT ZONE journal March 2016
Interseismic coupling and refined earthquake potential on the Hayward‐Calaveras fault zone journal December 2015
Spatial variations in fault friction related to lithology from rupture and afterslip of the 2014 South Napa, California, earthquake: THE 2014 SOUTH NAPA EARTHQUAKE AND AFTERSLIP journal July 2016
Age, origin, and thermal histories of some plutonic rocks from the Salinian block of California journal October 1978
Interseismic Strain Localization in the San Jacinto Fault Zone journal December 2013
A strike-slip fault in a laterally inhomogeneous medium journal October 1977
Geodetic exploration of the elastic properties across and within the northern San Andreas Fault zone journal October 2009
How well do surface slip measurements track slip at depth in large strike-slip earthquakes? The importance of fault structural maturity in controlling on-fault slip versus off-fault surface deformation journal February 2014
The potential for supershear earthquakes in damaged fault zones – theory and observations journal January 2016
Abrupt along-strike change in tectonic style: San Andreas Fault zone, San Francisco Peninsula journal May 1999
Low-velocity damaged structure of the San Andreas Fault at Parkfield from fault zone trapped waves: LOW-VELOCITY DAMAGED STRUCTURE OF THE SAN ANDREAS FAULT journal May 2004
Probing the mechanical properties of seismically active crust with space geodesy: Study of the coseismic deformation due to the 1992 M w 7.3 Landers (southern California) earthquake journal January 2004
Asymmetry in elastic properties and the evolution of large continental strike-slip faults journal January 2005
Slicing up the San Francisco Bay Area: Block kinematics and fault slip rates from GPS-derived surface velocities journal January 2005
Three-dimensional P wave velocity model for the San Francisco Bay region, California journal January 2007
Structure and mechanical properties of faults in the North Anatolian Fault system from InSAR observations of coseismic deformation due to the 1999 Izmit (Turkey) earthquake journal January 2007
Effect of a compliant fault zone on the inferred earthquake slip distribution journal January 2008
Large-scale relocation of two decades of Northern California seismicity using cross-correlation and double-difference methods: NORTHERN CALIFORNIA SEISMICITY RELOCATION journal August 2008
Locking depths estimated from geodesy and seismology along the San Andreas Fault System: Implications for seismic moment release journal January 2011
Geodetic slip rates in the southern San Andreas Fault system: Effects of elastic heterogeneity and fault geometry: SSAF SLIP RATES journal February 2013
The velocity field along the San Andreas Fault in central and southern California journal January 1991
Rise and fall of the southern Santa Cruz Mountains, California, from fission tracks, geomorphology, and geodesy journal October 1994
Three-dimensional upper crustal velocity structure beneath San Francisco Peninsula, California journal March 1997
The Black Mountain asperity: Seismic hazard of the southern San Francisco Peninsula, California journal October 1985
Geodetic determination of relative plate motion in central California journal February 1973
The determination of displacement fields from geodetic data along a strike slip fault journal July 1981
Interseismic strain accumulation and the earthquake potential on the southern San Andreas fault system journal June 2006
Equation of State Calculations by Fast Computing Machines journal June 1953
The San Andreas Fault in the San Francisco Bay Region, California: Structure and Kinematics of a Young Plate Boundary journal March 1999
Basic data features and results from a spatially dense seismic array on the San Jacinto fault zone journal May 2015
LII. An essay towards solving a problem in the doctrine of chances. By the late Rev. Mr. Bayes, F. R. S. communicated by Mr. Price, in a letter to John Canton, A. M. F. R. S journal January 1763
Evolution of the Northern Santa Cruz Mountains by Advection of Crust Past a San Andreas Fault Bend journal July 1990
Deeper penetration of large earthquakes on seismically quiescent faults journal June 2016
Seismic and geodetic evidence for extensive, long-lived fault damage zones journal April 2009
Geodetic Evidence for a Near-Fault Compliant Zone along the San Andreas Fault in the San Francisco Bay Area journal March 2002
A Unified Source Model for the 1906 San Francisco Earthquake journal April 2008
Uniform California Earthquake Rupture Forecast, Version 3 (UCERF3)--The Time-Independent Model journal June 2014
Using Surface Creep Rate to Infer Fraction Locked for Sections of the San Andreas Fault System in Northern California from Alignment Array and GPS Data journal October 2014
PyMC : Bayesian Stochastic Modelling in Python journal January 2010

Cited By (1)

Buried shallow fault slip from the South Napa earthquake revealed by near-field geodesy journal July 2017

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