Publications
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Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database Recalibration of the Mars Science Laboratory ChemCam instrument with an expanded geochemical database
The ChemCam Laser-Induced Breakdown Spectroscopy (LIBS) instrument onboard the Mars Science Laboratory (MSL) rover Curiosity has obtained > 300,000 spectra of rock and soil analysis targets since landing at Gale Crater in 2012, and the spectra represent perhaps the largest publicly-available LIBS datasets. The compositions of the major elements, reported as oxides (SiO2, TiO2, Al2O3...
Authors
Samuel M. Clegg, Roger C. Wiens, Ryan B. Anderson, Olivier Forni, Jens Frydenvang, Jeremie Lasue, Agnes Cousin, Valerie Payre, Tommy Boucher, M. Darby Dyar, Scott M. McLennan, Richard V. Morris, Trevor G. Graff, Stanley A Mertzman, Bethany L. Ehlmann, Ines Belgacem, Horton E. Newsom, Ben C. Clark, Noureddine Melikechi, Alissa Mezzacappa, Rhonda E. McInroy, Ronald Martinez, Patrick J. Gasda, Olivier Gasnault, Sylvestre Maurice
Unusual geologic evidence of coeval seismic shaking and tsunamis shows variability in earthquake size and recurrence in the area of the giant 1960 Chile earthquake Unusual geologic evidence of coeval seismic shaking and tsunamis shows variability in earthquake size and recurrence in the area of the giant 1960 Chile earthquake
An uncommon coastal sedimentary record combines evidence for seismic shaking and coincident tsunami inundation since AD 1000 in the region of the largest earthquake recorded instrumentally: the giant 1960 southern Chile earthquake (Mw 9.5). The record reveals significant variability in the size and recurrence of megathrust earthquakes and ensuing tsunamis along this part of the Nazca...
Authors
M. Cisternas, E Garrett, Robert L. Wesson, T. Dura, L. L Ely
Broadband seismic noise attenuation versus depth at the Albuquerque Seismological Laboratory Broadband seismic noise attenuation versus depth at the Albuquerque Seismological Laboratory
Seismic noise induced by atmospheric processes such as wind and pressure changes can be a major contributor to the background noise observed in many seismograph stations, especially those installed at or near the surface. Cultural noise such as vehicle traffic or nearby buildings with air handling equipment also contributes to seismic background noise. Such noise sources fundamentally...
Authors
Charles R. Hutt, Adam T. Ringler, Lind Gee
Subsurface volatile content of martian double-layer ejecta (DLE) craters Subsurface volatile content of martian double-layer ejecta (DLE) craters
Excess ice is widespread throughout the martian mid-latitudes, particularly in Arcadia Planitia, where double-layer ejecta (DLE) craters also tend to be abundant. In this region, we observe the presence of thermokarstically-expanded secondary craters that likely form from impacts that destabilize a subsurface layer of excess ice, which subsequently sublimates. The presence of these...
Authors
Donna Viola, Alfred S. McEwen, Colin M. Dundas, Shane Byrne
Systematic comparisons between PRISM version 1.0.0, BAP, and CSMIP ground-motion processing Systematic comparisons between PRISM version 1.0.0, BAP, and CSMIP ground-motion processing
A series of benchmark tests was run by comparing results of the Processing and Review Interface for Strong Motion data (PRISM) software version 1.0.0 to Basic Strong-Motion Accelerogram Processing Software (BAP; Converse and Brady, 1992), and to California Strong Motion Instrumentation Program (CSMIP) processing (Shakal and others, 2003, 2004). These tests were performed by using the...
Authors
Erol Kalkan, Christopher Stephens
Processing and review interface for strong motion data (PRISM) software, version 1.0.0—Methodology and automated processing Processing and review interface for strong motion data (PRISM) software, version 1.0.0—Methodology and automated processing
A continually increasing number of high-quality digital strong-motion records from stations of the National Strong-Motion Project (NSMP) of the U.S. Geological Survey (USGS), as well as data from regional seismic networks within the United States, call for automated processing of strong-motion records with human review limited to selected significant or flagged records. The NSMP has...
Authors
Jeanne Jones, Erol Kalkan, Christopher Stephens
Landslide kinematics and their potential controls from hourly to decadal timescales: Insights from integrating ground-based InSAR measurements with structural maps and long-term monitoring data Landslide kinematics and their potential controls from hourly to decadal timescales: Insights from integrating ground-based InSAR measurements with structural maps and long-term monitoring data
Knowledge of kinematics is rudimentary for understanding landslide controls and is increasingly valuable with greater spatiotemporal coverage. However, characterizing landslide-wide kinematics is rare, especially at broadly ranging timescales. We used highly detailed kinematic data obtained using photogrammetry and field mapping during the 1980s and 1990s and our 4.3-day ground-based...
Authors
William H. Schulz, Jeffrey A. Coe, P.P Ricci, Gregory M. Smoczyk, Brett L Shurtleff, J Panosky
Tsunamis: Bayesian probabilistic hazard analysis Tsunamis: Bayesian probabilistic hazard analysis
No abstract available.
Authors
Anita Grezio, Stefano Lorito, Tom Parsons, Jacopo Selva
Gravitational body forces focus North American intraplate earthquakes Gravitational body forces focus North American intraplate earthquakes
Earthquakes far from tectonic plate boundaries generally exploit ancient faults, but not all intraplate faults are equally active. The North American Great Plains exemplify such intraplate earthquake localization, with both natural and induced seismicity generally clustered in discrete zones. Here we use seismic velocity, gravity and topography to generate a 3D lithospheric density model...
Authors
William Brower Levandowski, Mark Zellman, Richard W. Briggs
Lithospheric density structure beneath the Tarim basin and surroundings, northwestern China, from the joint inversion of gravity and topography Lithospheric density structure beneath the Tarim basin and surroundings, northwestern China, from the joint inversion of gravity and topography
Intraplate strain generally focuses in discrete zones, but despite the profound impact of this partitioning on global tectonics, geodynamics, and seismic hazard, the processes by which deformation becomes localized are not well understood. Such heterogeneous intraplate strain is exemplified in central Asia, where the Indo-Eurasian collision has caused widespread deformation while the...
Authors
Yangfan Deng, William Brower Levandowski, Tim Kusky
Source modeling of the 2015 Mw 7.8 Nepal (Gorkha) earthquake sequence: Implications for geodynamics and earthquake hazards Source modeling of the 2015 Mw 7.8 Nepal (Gorkha) earthquake sequence: Implications for geodynamics and earthquake hazards
The Gorkha earthquake on April 25th, 2015 was a long anticipated, low-angle thrust-faulting event on the shallow décollement between the India and Eurasia plates. We present a detailed multiple-event hypocenter relocation analysis of the Mw 7.8 Gorkha Nepal earthquake sequence, constrained by local seismic stations, and a geodetic rupture model based on InSAR and GPS data. We integrate...
Authors
Daniel E. McNamara, William L. Yeck, William D. Barnhart, V. Schulte-Pelkum, E. Bergman, L. B. Adhikari, Amod Dixit, S. E. Hough, Harley M. Benz, Paul S. Earle
Chemistry of diagenetic features analyzed by ChemCam at Pahrump Hills, Gale crater, Mars Chemistry of diagenetic features analyzed by ChemCam at Pahrump Hills, Gale crater, Mars
The Curiosity rover's campaign at Pahrump Hills provides the first analyses of lower Mount Sharp strata. Here we report ChemCam elemental composition of a diverse assemblage of post-depositional features embedded in, or cross-cutting, the host rock. ChemCam results demonstrate their compositional diversity, especially compared to the surrounding host rock: (i) Dendritic aggregates and...
Authors
Marion Nachon, Nicolas Mangold, Olivier Forni, Linda C. Kah, Agnes Cousin, Roger C. Wiens, Ryan B. Anderson, Diana L. Blaney, Jen G. Blank, Fred J. Calef, Samuel M. Clegg, Cecile Fabre, Martin R. Fisk, Olivier Gasnault, John P. Grotzinger, Rachel Kronyak, Nina L. Lanza, Jeremie Lasue, Laetitia Le Deit, Stephane Le Mouelic, Sylvestre Maurice, Pierre-Yves Meslin, D. Z. Oehler, Valerie Payre, William Rapin, Susanne Schroder, Katherine M. Stack, Dawn Sumner