Publications
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Micrometer-scale U–Pb age domains in eucrite zircons, impact re-setting, and the thermal history of the HED parent body
Meteoritic zircons are rare, but some are documented to occur in asteroidal meteorites, including those of the howardite–eucrite–diogenite (HED) achondrite clan (Rubin, A. [1997]. Meteorit. Planet. Sci. 32, 231–247). The HEDs are widely considered to originate from the Asteroid 4 Vesta. Vesta and the other large main belt asteroids record an early bombardment history. To explore this record, we de
Authors
M.D. Hopkins, S.J. Mojzsis, W.F. Bottke, Oleg Abramov
Astronomical observations of volatiles on asteroids
We have long known that water and hydroxyl are important components in meteorites and asteroids. However, in the time since the publication of Asteroids III, evolution of astronomical instrumentation, laboratory capabilities, and theoretical models have led to great advances in our understanding of H2O/OH on small bodies, and spacecraft observations of the Moon and Vesta have important implication
Authors
Andrew S. Rivkin, Humberto Campins, Joshua P. Emery, Ellen S. Howell, Javier Licandro, Driss Takir, Faith Vilas
Chronology and ecology of late Pleistocene megafauna in the northern Willamette Valley, Oregon
Since the mid-19th century, western Oregon's Willamette Valley has been a source of remains from a wide variety of extinct megafauna. Few of these have been previously described or dated, but new chronologic and isotopic analyses in conjunction with updated evaluations of stratigraphic context provide substantial new information on the species present, timing of losses, and paleoenvironmental cond
Authors
Daniel M. Gilmour, Virginia L. Butler, James E. O'Connor, Edward Byrd Davis, Brendan J. Culleton, Douglas J. Kennett, Gregory W. L. Hodgins
Understanding the signature of rock coatings in laser-induced breakdown spectroscopy data
Surface compositional features on rocks such as coatings and weathering rinds provide important information about past aqueous environments and water–rock interactions. The search for these features represents an important aspect of the Curiosity rover mission. With its unique ability to do fine-scale chemical depth profiling, the ChemCam laser-induced breakdown spectroscopy instrument (LIBS) onbo
Authors
Nina L. Lanza, Ann M. Ollila, Agnès Cousin, Roger C. Wiens, Samuel M. Clegg, Nicolas Mangold, Nathan Bridges, Daniel Cooper, Mariek E. Schmidt, Jeffrey Berger, Raymond E. Arvidson, Noureddine Melikechi, Horton E. Newsom, Robert Tokar, Craig Hardgrove, Alissa Mezzacappa, Ryan S. Jackson, Benton C. Clark, Olivier Forni, Sylvestre Maurice, Marion Nachon, Ryan B. Anderson, Jennifer Blank, Matthew Deans, Dorothea Delapp, Richard Léveillé, Rhonda McInroy, Ronald Martinez, Pierre-Yves Meslin, Patrick Pinet
The use of wavenumber normalization in computing spatially averaged coherencies (KRSPAC) of microtremor data from asymmetric arrays
The SPAC method of processing microtremor noise observations for estimation of Vs profiles has a limitation that the array has circular or triangular symmetry in order to allow spatial (azimuthal) averaging of inter-station coherencies over a constant station separation. Common processing methods allow for station separations to vary by typically ±10% in the azimuthal averaging before degradation
Authors
M.W. Asten, William J. Stephenson, Stephen H. Hartzell
How to build and teach with QuakeCaster: an earthquake demonstration and exploration tool
QuakeCaster is an interactive, hands-on teaching model that simulates earthquakes and their interactions along a plate-boundary fault. QuakeCaster contains the minimum number of physical processes needed to demonstrate most observable earthquake features. A winch to steadily reel in a line simulates the steady plate tectonic motions far from the plate boundaries. A granite slider in frictional con
Authors
Kelsey Linton, Ross S. Stein
Asteroid photometry
Asteroid photometry has three major applications: providing clues about asteroid surface physical properties and compositions, facilitating photometric corrections, and helping design and plan ground-based and spacecraft observations. The most significant advances in asteroid photometry in the past decade were driven by spacecraft observations that collected spatially resolved imaging and spectro
Authors
Jian-Yang Li, Paul Helfenstein, Bonnie J. Buratti, Driss Takir, Beth Ellen Clark
Crowdsourced earthquake early warning
Earthquake early warning (EEW) can reduce harm to people and infrastructure from earthquakes and tsunamis, but it has not been implemented in most high earthquake-risk regions because of prohibitive cost. Common consumer devices such as smartphones contain low-cost versions of the sensors used in EEW. Although less accurate than scientific-grade instruments, these sensors are globally ubiquitous.
Authors
Sarah E. Minson, Benjamin A. Brooks, Craig L. Glennie, Jessica R. Murray, John O. Langbein, Susan E. Owen, Thomas H. Heaton, Robert A. Iannucci, Darren L. Hauser
Validation of the SCEC broadband platform V14.3 simulation methods using pseudo spectral acceleration data
This paper summarizes the evaluation of ground motion simulation methods implemented on the SCEC Broadband Platform (BBP), version 14.3 (as of March 2014). A seven-member panel, the authorship of this article, was formed to evaluate those methods for the prediction of pseudo-‐spectral accelerations (PSAs) of ground motion. The panel’s mandate was to evaluate the methods using tools developed thro
Authors
Douglas S. Dreger, Gregory C. Beroza, Steven M. Day, Christine A. Goulet, Thomas H Jordan, Paul A. Spudich, Jonathan P. Stewart
Introduction: Hazard mapping
Twenty papers were accepted into the session on landslide hazard mapping for oral presentation. The papers presented susceptibility and hazard analysis based on approaches ranging from field-based assessments to statistically based models to assessments that combined hydromechanical and probabilistic components. Many of the studies have taken advantage of increasing availability of remotely sensed
Authors
Rex L. Baum, Toyohiko Miyagi, Saro Lee, Oleksandr M Trofymchuk
Micro-seismicity and seismic moment release within the Coso Geothermal Field, California
We relocate 16 years of seismicity in the Coso Geothermal Field (CGF) using differential travel times and simultaneously invert for seismic velocities to improve our knowledge of the subsurface geologic and hydrologic structure. We expand on our previous results by doubling the number of relocated events from April 1996 through May 2012 using a new field-wide 3-D velocity model. Relocated micro-se
Authors
J. Ole Kaven, Stephen H. Hickman, Nicholas C. Davatzes
Seismic monitoring at the Decatur, Ill., CO2 sequestration demonstration site
The viability of carbon capture and storage (CCS) to reduce emissions of greenhouse gases depends on the ability to safely sequester large quantities of CO2 over geologic time scales. One concern with CCS is the potential of induced seismicity. We report on ongoing seismic monitoring by the U.S. Geological Survey (USGS) at a CCS demonstration site in Decatur, IL, in an effort to understand the pot
Authors
J. Ole Kaven, Stephen H. Hickman, Arthur F. McGarr, Steve R. Walter, William L. Ellsworth