Publications
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Normal-faulting slip maxima and stress-drop variability: A geological perspective
We present an empirical estimate of maximum slip in continental normal-faulting earthquakes and present evidence that stress drop in intraplate extensional environments is dependent on fault maturity. A survey of reported slip in historical earthquakes globally and in latest Quaternary paleoearthquakes in the Western Cordillera of the United States indicates maximum vertical displacements as large
Authors
Suzanne Hecker, T. E. Dawson, D. P. Schwartz
Liquefaction caused by the 2009 Olancha, California (USA), M5.2 earthquake
The October 3, 2009 (01:16:00 UTC), Olancha M5.2 earthquake caused extensive liquefaction as well as permanent horizontal ground deformation within a 1.2 km2area earthquake in Owens Valley in eastern California (USA). Such liquefaction is rarely observed during earthquakes of M ≤ 5.2. We conclude that subsurface conditions, not unusual ground motion, were the primary factors contributing to the li
Authors
T.L. Holzer, A. S. Jayko, E. Hauksson, J.P.B. Fletcher, T.E. Noce, M.J. Bennett, C.M. Dietel, K.W. Hudnut
Decay of aftershock density with distance does not indicate triggering by dynamic stress
Resolving whether static or dynamic stress triggers most aftershocks and subsequent mainshocks is essential to understand earthquake interaction and to forecast seismic hazard. Felzer and Brodsky examined the distance distribution of earthquakes occurring in the first five minutes after 2 ≤ M
Authors
K. Richards-Dinger, R. S. Stein, S. Toda
Methane hydrate synthesis from ice: Influence of pressurization and ethanol on optimizing formation rates and hydrate yield
Polycrystalline methane gas hydrate (MGH) was synthesized using an ice-seeding method to investigate the influence of pressurization and ethanol on the hydrate formation rate and gas yield of the resulting samples. When the reactor is pressurized with CH4 gas without external heating, methane hydrate can be formed from ice grains with yields up to 25% under otherwise static conditions. The rapid t
Authors
Po-Chun. Chen, Wuu-Liang Huang, Laura A. Stern
Observing the Greatest Earthquakes: AGU Chapman Conference on Giant Earthquakes and Their Tsunamis: Viña del Mar and Valparaíso, Chile, 16–20 May 2010
An AGU Chapman Conference commemorated the fiftieth anniversary of the 1960 M 9.5 Chile earthquake. Participants reexamined this earthquake, the largest ever recorded instrumentally, and compared it with Chile's February 2010 M 8.8 earthquake. They also addressed the giant earthquake potential of subduction zones worldwide and strategies for reducing losses due to tsunamis. The conference drew 96
Authors
Brian F. Atwater, Sergio Barrientos, Inés Cifuentes, Marco Cisternas, Kelin Wang
Viscoelastic-cycle model of interseismic deformation in the northwestern United States
We apply a viscoelastic cycle model to a compilation of GPS velocity fields in order to address the kinematics of deformation in the northwestern United States. A viscoelastic cycle model accounts for time-dependent deformation following large crustal earthquakes and is an alternative to block models for explaining the interseismic crustal velocity field. Building on the approach taken in Pollitz
Authors
F. F. Pollitz, Patricia McCrory, Doug Wilson, Jerry Svarc, Christine Puskas, Robert B. Smith
Correction to “Constraints on the stress state of the San Andreas Fault with analysis based on core and cuttings from San Andreas Fault Observatory at Depth (SAFOD) drilling phases 1 and 2”
This article corrects: Constraints on the stress state of the San Andreas Fault with analysis based on core and cuttings from San Andreas Fault Observatory at Depth (SAFOD) drilling phases 1 and 2. Vol. 114, Issue B11, Article first published online: 5 NOV 2009.
Authors
Sheryl Tembe, David Lockner, Teng-Fong Wong
Effect of clay content and mineralogy on frictional sliding behavior of simulated gouges: binary and ternary mixtures of quartz, illite, and montmorillonite
We investigated the frictional sliding behavior of simulated quartz-clay gouges under stress conditions relevant to seismogenic depths. Conventional triaxial compression tests were conducted at 40 MPa effective normal stress on saturated saw cut samples containing binary and ternary mixtures of quartz, montmorillonite, and illite. In all cases, frictional strengths of mixtures fall between the end
Authors
Sheryl Tembe, David A. Lockner, Teng-Fong Wong
Rupture directivity of moderate earthquakes in northern California
We invert peak ground velocity and acceleration (PGV and PGA) to estimate rupture direction and rupture velocity for 47 moderate earthquakes (3.5≥M≥5.4) in northern California. We correct sets of PGAs and PGVs recorded at stations less than 55–125 km, depending on source depth, for site amplification and source–receiver distance, then fit the residual peak motions to the unilateral directivity fun
Authors
Linda C. Seekins, John Boatwright
The effect of error in theoretical Earth tide on calibration of borehole strainmeters
Since the installation of borehole strainmeters into the ground locally distorts the strain in the rock, these strainmeters require calibration from a known source which typically is the Earth tide. Consequently, the accuracy of the observed strain changes from borehole strainmeters depends upon the calibration derived from modeling the Earth tide. Previous work from the mid-1970s, which is replic
Authors
John Langbein
Low-altitude aerial color digital photographic survey of the San Andreas Fault
Ever since 1858, when Gaspard-Félix Tournachon (pen name Félix Nadar) took the first aerial photograph (Professional Aerial Photographers Association 2009), the scientific value and popular appeal of such pictures have been widely recognized. Indeed, Nadar patented the idea of using aerial photographs in mapmaking and surveying. Since then, aerial imagery has flourished, eventually making the leap
Authors
David K. Lynch, Kenneth W. Hudnut, David S.P. Dearborn
230Th/U dating of a late Pleistocene alluvial fan along the southern San Andreas fault
U-series dating of pedogenic carbonate-clast coatings provides a reliable, precise minimum age of 45.1 ± 0.6 ka (2σ) for the T2 geomorphic surface of the Biskra Palms alluvial fan, Coachella Valley, California. Concordant ages for multiple subsamples from individual carbonate coatings provide evidence that the 238U-234U-230Th system has remained closed since carbonate formation. The U-series minim
Authors
Kathryn E.K. Fletcher, Warren D. Sharp, Katherine J. Kendrick, Whitney M. Behr, Kenneth W. Hudnut, Thomas C. Hanks