Publications
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Seismic design and hazard maps: Before and after
The 1994 Northridge earthquake generated world-record ground motions. At the time, the horizontal peak ground acceleration of 1.8 g measured by a seismometer in Tarzana was the largest ever. The same is true of the peak ground velocity of 148 cm/s measured in Granada Hills. Both measurements were within approximately 15 km of the source of the earthquake; they were also near most of the damage des
Authors
Nicolas Luco
Refining the Baseline Sediment Budget for the Klamath River, California
Four dams in the Klamath River Hydroelectric Project (KHP) in Oregon and California (Figure 1) are currently scheduled to be removed over a period of a few weeks or months, beginning in January 2021. The Klamath dam removal will be the largest in the world by almost all measures, and is an unprecedented opportunity to advance science of river responses to such events. The KHP contains approximatel
Authors
Chauncey W. Anderson, Scott Wright, Liam N. Schenk, Katherine Skalak, Jennifer A. Curtis, Amy E. East, Adam Benthem
Morphology and genesis of giant seafloor depressions on the southeasterncontinental shelf of the Korean Peninsula
We identify and describe five giant seafloor depressions from the southeastern continental shelf of the Korean Peninsula using multibeam bathymetry, sub-bottom profiler, and multi-channel seismic reflection data, supplemented by piston cores. Multibeam bathymetry data from the shelf show four crescent-shaped depressions (SD1 to SD4) and one near-circular depression (SD5) within a group of NW-SE tr
Authors
Deniz Cukur, Gee-Soo Kong, Jong-Hwa Chun, Moo-Hee Kang, In-Kwon Um, Taekhyun Kwon, Samuel E. Jordan, Kyong-O Kim
Petrologic and mineral physics database for use with the U.S. Geological Survey National Crustal Model
We present a petrologic and mineral physics database as part of the U.S. Geological Survey National Crustal Model (NCM). Each of 209 geologic units, 134 of which are currently part of the geologic framework within the NCM, was assigned a mineralogical composition according to generalized classifications with some refinement for specific geologic formations. This report is concerned with the petrol
Authors
Theron Sowers, Oliver S. Boyd
A combinatorial approach to determine earthquake magnitude distributions on a variable slip-rate fault
Combinatorial methods are used to determine the spatial distribution of earthquake magnitudes on a fault whose slip rate varies along strike. Input to the problem is a finite sample of earthquake magnitudes that span 5 kyr drawn from a truncated Pareto distribution. The primary constraints to the problem are maximum and minimum values around the target slip-rate function indicating where feasible
Authors
Eric L. Geist, Thomas E. Parsons
The major coral reefs of Maui Nui, Hawai‘i—distribution, physical characteristics, oceanographic controls, and environmental threats
Coral reefs are widely recognized as critical to Hawaiʻi’s economy, food resources, and protection from damaging storm waves. Yet overfishing, land-based pollution, and climate change are threatening the health and sustainability of those reefs, and accordingly, both the Federal and State governments have called for protection and effective management. In 2000, the U.S. Coral Reef Task Force state
Authors
Michael E. Field, Curt D. Storlazzi, Ann E. Gibbs, Nicole L. D'Antonio, Susan A. Cochran
Satellite observations of surface deformation at the Coso Geothermal Field, California
Surface deformation time series and rates are identified at the Coso Geothermal Field (CGF) and surrounding areas by applying interferometric synthetic aperture radar (InSAR) to satellite scenes from Envisat (June 2004 ̶ October 2010) and Sentinel (November 2014 – April 2018). The measurements are done in the line of sight (LOS) to each satellite, within an area of size ~450 km2, at the location
Authors
Mariana Eneva, Andrew Barbour, David Adams, Vicky Hsiao, Kelly Blake, Giacomo Falorni, Roberto Locatelli
Landscape change associated with the upper Scenic Drive landslide, La Honda, California, January 10–June 28, 2017
La Honda, California, is a small town in unincorporated San Mateo County, located on the west edge of the San Francisco Peninsula in the Santa Cruz Mountains, between San Francisco and San Jose. The Scenic Drive area of La Honda has experienced several past episodes of landslide motion, which were documented in 1998, 2005, and 2006. This report documents the movement of the upper Scenic Drive land
Authors
Alexandra J. Pickering, Carol S. Prentice, Stephen B. DeLong
Variability in synthetic earthquake ground motions caused by source variability and errors in wave propagation models
Numerical simulations of earthquake ground motions are used both to anticipate the effects of hypothetical earthquakes by forward simulation and to infer the behaviour of the real earthquake source ruptures by the inversion of recorded ground motions. In either application it is necessary to assume some Earth structure that is necessarily inaccurate and to use a computational method that is also i
Authors
Paul A. Spudich, Antonella Cirella, Laura Scognamiglio, Elisa Tinti
Coastal and marine science of the U.S. Geological Survey in Woods Hole, Massachusetts
The U.S. Geological Survey (USGS) Woods Hole Coastal and Marine Science Center in Woods Hole, Massachusetts, is one of three centers serving the mission of the USGS Coastal and Marine Hazards and Resources Program (CMHRP). Since its authorization by Congress in 1962, the CMHRP has served as the primary Federal program for marine geology and physical science research and is responsible for the Nati
Authors
Sara Ernst
Determining Moho depth beneath sedimentary basins using regional Pn multiples
The study of the Moho beneath thick sedimentary basins involving natural earthquakes is challenging, as low‐velocity materials often cause strong reverberations that mask Moho signals. Here, we develop a method to determine the depth of the Moho by taking advantage of the presence of the sediments. The method utilizes the first Pn crustal multiple from regional earthquakes PnPn and its differentia
Authors
C. Yu, Z. Zhan, E. Hauksson, Elizabeth S. Cochran, D. Helmberger
Widespread initiation, reactivation, and acceleration of landslides in the northern California Coast Ranges due to extreme rainfall
Episodically to continuously active slow-moving landslides are driven by precipitation.
Climate change, which is altering both the frequency and magnitude of precipitation world21
wide, is therefore predicted to have a major impact on landslides. Here we examine the
behavior of hundreds of slow-moving landslides in northern California in response to large
changes in annual precipitation that oc
Authors
Alexander L. Handwerger, Eric J. Fielding, Mong-Han Huang, Georgina L. Bennett, Cunren Liang, William Schulz