Publications
Filter Total Items: 2073
Building a subduction zone observatory Building a subduction zone observatory
Subduction zones contain many of Earth’s most remarkable geologic structures, from the deepest oceanic trenches to glacier-covered mountains and steaming volcanoes. These environments formed through spectacular events: Nature’s largest earthquakes, tsunamis, and volcanic eruptions are born here.
Authors
Joan S. Gomberg, Paul Bodin, Jody Bourgeois, Susan Cashman, Darrel Cowan, Kenneth C. Creager, Brendan Crowell, Alison Duvall, Arthur D. Frankel, Frank I. Gonzalez, Heidi Houston, Paul Johnson, Harvey Kelsey, Una Miller, Emily C. Roland, David Schmidt, Lydia M. Staisch, John Vidale, William Wilcock, Erin Wirth
Lithospheric flexure under the Hawaiian volcanic load: Internal stresses and a broken plate revealed by earthquakes Lithospheric flexure under the Hawaiian volcanic load: Internal stresses and a broken plate revealed by earthquakes
Several lines of earthquake evidence indicate that the lithospheric plate is broken under the load of the island of Hawai`i, where the geometry of the lithosphere is circular with a central depression. The plate bends concave downward surrounding a stress-free hole, rather than bending concave upward as with past assumptions. Earthquake focal mechanisms show that the center of load...
Authors
Fred W. Klein
Summary of the GK15 ground‐motion prediction equation for horizontal PGA and 5% damped PSA from shallow crustal continental earthquakes Summary of the GK15 ground‐motion prediction equation for horizontal PGA and 5% damped PSA from shallow crustal continental earthquakes
We present a revised ground‐motion prediction equation (GMPE) for computing medians and standard deviations of peak ground acceleration (PGA) and 5% damped pseudospectral acceleration (PSA) response ordinates of the horizontal component of randomly oriented ground motions to be used for seismic‐hazard analyses and engineering applications. This GMPE is derived from the expanded Next...
Authors
Vladimir; Graizer, Erol Kalkan
NGA-West2 equations for predicting vertical-component PGA, PGV, and 5%-damped PSA from shallow crustal earthquakes NGA-West2 equations for predicting vertical-component PGA, PGV, and 5%-damped PSA from shallow crustal earthquakes
We present ground motion prediction equations (GMPEs) for computing natural log means and standard deviations of vertical-component intensity measures (IMs) for shallow crustal earthquakes in active tectonic regions. The equations were derived from a global database with M 3.0–7.9 events. The functions are similar to those for our horizontal GMPEs. We derive equations for the primary M-...
Authors
Jonathan P. Stewart, David M. Boore, Emel Seyhan, Gail M. Atkinson
Postseismic gravity change after the 2006–2007 great earthquake doublet and constraints on the asthenosphere structure in the central Kuril Islands Postseismic gravity change after the 2006–2007 great earthquake doublet and constraints on the asthenosphere structure in the central Kuril Islands
Large earthquakes often trigger viscoelastic adjustment for years to decades depending on the rheological properties and the nature and spatial extent of coseismic stress. The 2006 Mw8.3 thrust and 2007 Mw8.1 normal fault earthquakes of the central Kuril Islands resulted in significant postseismic gravity change in Gravity Recovery and Climate Experiment (GRACE) but without a discernible...
Authors
Shin-Chan Han, Jeanne Sauber, Frederick Pollitz
Tomographic Rayleigh-wave group velocities in the Central Valley, California centered on the Sacramento/San Joaquin Delta Tomographic Rayleigh-wave group velocities in the Central Valley, California centered on the Sacramento/San Joaquin Delta
If shaking from a local or regional earthquake in the San Francisco Bay region were to rupture levees in the Sacramento/San Joaquin Delta then brackish water from San Francisco Bay would contaminate the water in the Delta: the source of fresh water for about half of California. As a prelude to a full shear-wave velocity model that can be used in computer simulations and further seismic...
Authors
Jon Peter B. Fletcher, Jemile Erdem, Kevin Seats, Jesse Lawrence
Detailed mapping and rupture implications of the 1 km releasing bend in the Rodgers Creek Fault at Santa Rosa, northern California Detailed mapping and rupture implications of the 1 km releasing bend in the Rodgers Creek Fault at Santa Rosa, northern California
Airborne light detection and ranging (lidar) topography reveals for the first time the trace of the Rodgers Creek fault (RCF) through the center of Santa Rosa, the largest city in the northern San Francisco Bay area. Vertical deformation of the Santa Rosa Creek floodplain expresses a composite pull‐apart basin beneath the urban cover that is part of a broader 1‐km‐wide right‐releasing...
Authors
Suzanne Hecker, Victoria E. Langenheim, Robert Williams, Christopher S. Hitchcock, Stephen B. DeLong
Evaluation of six NEHRP B/C crustal amplification models proposed for use in western North America Evaluation of six NEHRP B/C crustal amplification models proposed for use in western North America
We evaluate six crustal amplification models based on National Earthquake Hazards Reduction Program (NEHRP) B/C crustal profiles proposed for use in western North America (WNA) and often used in other active crustal regions where crustal properties are unknown. One of the models is based on an interpolation of generic rock velocity profiles previously proposed for WNA and central and...
Authors
David Boore, Kenneth W. Campbell
Geomorphic and geologic controls of geohazards induced by Nepal’s 2015 Gorkha earthquake Geomorphic and geologic controls of geohazards induced by Nepal’s 2015 Gorkha earthquake
The Gorkha earthquake (magnitude 7.8) on 25 April 2015 and later aftershocks struck South Asia, killing ~9000 people and damaging a large region. Supported by a large campaign of responsive satellite data acquisitions over the earthquake disaster zone, our team undertook a satellite image survey of the earthquakes’ induced geohazards in Nepal and China and an assessment of the geomorphic...
Authors
J.S. Kargel, G.J. Leonard, D. H. Shugar, U. K. Haritashya, A. Bevington, E.J. Fielding, K. Fujita, M. Geertsema, E. S. Miles, J. Steiner, E. Anderson, S. Bajracharya, G.W. Bawden, D. F. Breashears, A. Byers, B. Collins, M. R. Dhital, A. Donnellan, T. L. Evans, M. L. Geai, M. T. Glasscoe, D. Green, D. R. Gurung, R. Heijenk, A. Hilborn, K. Hudnut, C. Huyck, W. W. Immerzeel, Jiang Li, R. Jibson, A. Kaab, N. R. Khanal, D. Kirschbaum, P. D. A. Kraaijenbrink, D. Lamsal, Liu Shiyin, Lv Mingyang, D. McKinney, N. K. Nahirnick, Nan Zhuotong, S. Ojha, J. Olsenholler, T. H. Painter, M. Pleasants, K. C. Pratima, Q. I. Yuan, B.H. Raup, D. Regmi, D. R. Rounce, A. Sakai, Shangguan Donghui, J. M. Shea, A. B. Shrestha, A. Shukla, D. Stumm, M. van der Kooij, K. Voss, Wang Xin, B. Weihs, Wu Lizong, Yao Xiaojun, M. R. Yoder, N. Young
“Ductile to brittle” transition in thermally stable antigorite gouge at mantle pressures “Ductile to brittle” transition in thermally stable antigorite gouge at mantle pressures
General shear experiments on antigorite-rich serpentinite show a transition from ductile (distributed) to brittle (localized) deformation with increasing temperature from 300°C to 500°C at confining pressures from 1 to 2 GPa. The coefficient of friction associated with slip along fractures decreases from 0.23 to 0.07 with an increase in temperature from 300°C to 500°C. Velocity stepping
Authors
Brooks P. Proctor, Greg Hirth
Afterslip behavior following the M6.0, 2014 South Napa earthquake with implications for afterslip forecasting on other seismogenic faults Afterslip behavior following the M6.0, 2014 South Napa earthquake with implications for afterslip forecasting on other seismogenic faults
The M6.0, 24 Aug. 2014 South Napa, California, earthquake exhibited unusually large slip for a California strike-slip event of its size with a maximum coseismic surface slip of 40-50 cm in the north section of the 15 km-long rupture. Although only minor (
Authors
James J. Lienkaemper, Stephen B. DeLong, Carolyn J Domrose, Carla M. Rosa
Comparison of measurement- and proxy-based Vs30 values in California Comparison of measurement- and proxy-based Vs30 values in California
This study was prompted by the recent availability of a significant amount of openly accessible measured VS30 values and the desire to investigate the trend of using proxy-based models to predict VS30 in the absence of measurements. Comparisons between measured and model-based values were performed. The measured data included 503 VS30 values collected from various projects for 482...
Authors
Alan K. Yong