Publications
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A revised surface age for the North Polar Layered Deposits of Mars A revised surface age for the North Polar Layered Deposits of Mars
The North Polar Layered Deposits (NPLD) of Mars contain a complex stratigraphy that has been suggested to retain a record of past eccentricity- and obliquity-forced climate changes. The surface accumulation rate in the current climate can be constrained by the crater retention age. We scale NPLD crater diameters to account for icy target strength and compare surface age using a new...
Authors
Margaret E. Landis, Shane Byrne, Ingrid J. Daubar, Kenneth E. Herkenhoff, Colin M. Dundas
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
An overview of current applications, challenges, and future trends in distributed process-based models in hydrology An overview of current applications, challenges, and future trends in distributed process-based models in hydrology
Process-based hydrological models have a long history dating back to the 1960s. Criticized by some as over-parameterized, overly complex, and difficult to use, a more nuanced view is that these tools are necessary in many situations and, in a certain class of problems, they are the most appropriate type of hydrological model. This is especially the case in situations where knowledge of...
Authors
Simone Fatichi, Enrique R. Vivoni, Fred L Odgen, Valeriy Y Ivanov, Benjamin B. Mirus, David Gochis, Charles W Downer, Matteo Camporese, Jason H Davison, Brian A. Ebel, Norm Jones, Jon Kim, Giuseppe Mascaro, Richard G. Niswonger, Pedro Restrepo, Riccardo Rigon, Chaopeng Shen, Mauro Sulis, David Tarboton
RMT focal plane sensitivity to seismic network geometry and faulting style RMT focal plane sensitivity to seismic network geometry and faulting style
Modern tectonic studies often use regional moment tensors (RMTs) to interpret the seismotectonic framework of an earthquake or earthquake sequence; however, despite extensive use, little existing work addresses RMT parameter uncertainty. Here, we quantify how network geometry and faulting style affect RMT sensitivity. We examine how data-model fits change with fault plane geometry...
Authors
Kendra L. Johnson, Gavin P. Hayes, Robert B. Herrmann, Harley M. Benz, Daniel E. McNamara, Eric A. Bergman
Seismic site characterization of an urban dedimentary basin, Livermore Valley, California: Site tesponse, basin-edge-induced surface waves, and 3D simulations Seismic site characterization of an urban dedimentary basin, Livermore Valley, California: Site tesponse, basin-edge-induced surface waves, and 3D simulations
Thirty‐two accelerometers were deployed in the Livermore Valley, California, for approximately one year to study sedimentary basin effects. Many local and near‐regional earthquakes were recorded, including the 24 August 2014 Mw 6.0 Napa, California, earthquake. The resulting ground‐motion data set is used to quantify the seismic response of the Livermore basin, a major structural...
Authors
Stephen H. Hartzell, Alena L. Leeds, Leonardo Ramirez-Guzman, James P. Allen, Robert G. Schmitt
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
The Galapagos archipelago: A natural laboratory to examine sharp hydroclimatic, geologic and anthropogenic gradients The Galapagos archipelago: A natural laboratory to examine sharp hydroclimatic, geologic and anthropogenic gradients
Poor understanding of the water cycle in tropical ecosystems has the potential to exacerbate water shortages and water crises in the region. We suggest that the Galápagos Islands provide an excellent proxy to regions across the tropics as a result of sharp hydroclimatic, anthropogenic, and pedohydrologic gradients across the archipelago. Hydroclimatic and pedohydrologic gradients are...
Authors
Madelyn Percy, Sarah Schmitt, Diego Riveros-Iregui, Benjamin B. Mirus
Composition of conglomerates analyzed by the Curiosity rover: Implications for Gale Crater crust and sediment sources Composition of conglomerates analyzed by the Curiosity rover: Implications for Gale Crater crust and sediment sources
No abstract available.
Authors
Nicolas Mangold, L.M. Thompson, O. Forni, C. Fabre, L. Le Deit, R. C. Wiens, A.J. Williams, R. Williams, Ryan B. Anderson, Diana L. Blaney, Fred J. Calef, Agnes Cousin, Samuel M. Clegg, Gilles Dromart, William E. Dietrich, Kenneth S. Edgett, Martin R. Fisk, Olivier Gasnault, Ralf Gellert, John P. Grotzinger, Linda C. Kah, Stephane Le Mouelic, Scott M. McLennan, Sylvestre Maurice, Pierre-Yves Meslin, Horton E. Newsom, Marisa C. Palucis, William Rapin, Violaine Sautter, Kirsten L. Siebach, Katherine M. Stack, Dawn Y. Sumner, Aileen Yingst
Relationships between diatoms and tidal environments in Oregon and Washington, USA Relationships between diatoms and tidal environments in Oregon and Washington, USA
A new regional dataset comprising 425 intertidal diatom taxa from 175 samples from 11 ecologically diverse Oregon and Washington estuaries illustrates the importance of compiling a large modern dataset from a range of sites. Cluster analyses and detrended correspondence analysis of the diatom assemblages identify distinct vertical zones within supratidal, intertidal and subtidal...
Authors
Yuki Sawai, Benjamin P. Horton, Andrew C. Kemp, Andrea D. Hawkes, Tamostsu Nagumo, Alan R. Nelson
USGS approach to real-time estimation of earthquake-triggered ground failure - Results of 2015 workshop USGS approach to real-time estimation of earthquake-triggered ground failure - Results of 2015 workshop
The U.S. Geological Survey (USGS) Earthquake Hazards and Landslide Hazards Programs are developing plans to add quantitative hazard assessments of earthquake-triggered landsliding and liquefaction to existing real-time earthquake products (ShakeMap, ShakeCast, PAGER) using open and readily available methodologies and products. To date, prototype global statistical models have been...
Authors
Kate E. Allstadt, Eric M. Thompson, David J. Wald, Michael W. Hamburger, Jonathan W. Godt, Keith L. Knudsen, Randall W. Jibson, M. Anna Jessee, Jing Zhu, Michael Hearne, Laurie G. Baise, Hakan Tanyas, Kristin D. Marano