Publications
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Using micro-seismicity and seismic velocities to map subsurface geologic and hydrologic structure within the Coso geothermal field, California
Geothermal reservoirs derive their capacity for fluid and heat transport in large part from faults and fractures. Micro-seismicity generated on such faults and fractures can be used to map larger fault structures as well as secondary fractures that add access to hot rock, fluid storage and recharge capacity necessary to have a sustainable geothermal resource. Additionally, inversion of seismic vel
Authors
Joern Ole Kaven, Stephen H. Hickman, Nicholas C. Davatzes
Long-term creep rates on the Hayward Fault: Evidence for controls on the size and frequency of large earthquakes
The Hayward fault (HF) in California exhibits large (Mw 6.5–7.1) earthquakes with short recurrence times (161±65 yr), probably kept short by a 26%–78% aseismic release rate (including postseismic). Its interseismic release rate varies locally over time, as we infer from many decades of surface creep data. Earliest estimates of creep rate, primarily from infrequent surveys of offset cultural featur
Authors
James J. Lienkaemper, Forrest S. McFarland, Robert W. Simpson, Roger G. Bilham, David A. Ponce, John Boatwright, S. John Caskey
Ocean-atmosphere dynamics during Hurricane Ida and Nor'Ida: An application of the coupled ocean-;atmosphere–wave–sediment transport (COAWST) modeling system
The coupled ocean–atmosphere–wave–sediment transport (COAWST) modeling system was used to investigate atmosphere–ocean–wave interactions in November 2009 during Hurricane Ida and its subsequent evolution to Nor'Ida, which was one of the most costly storm systems of the past two decades. One interesting aspect of this event is that it included two unique atmospheric extreme conditions, a hurricane
Authors
Maitane Olabarrieta, John C. Warner, Brandy N. Armstrong, Joseph B. Zambon, Ruoying He
Inflation rates, rifts, and bands in a pāhoehoe sheet flow
The margins of sheet flows—pāhoehoe lavas emplaced on surfaces sloping
Authors
Richard P. Hoblitt, Tim R. Orr, Christina Heliker, Roger P. Denlinger, Ken Hon, Peter F. Cervelli
Effects of smectite to illite transformation on the frictional strength and sliding stability of intact marine mudstones
At subduction zones, earthquake nucleation and coseismic slip occur only within a limited depth range, known as the “seismogenic zone”. One leading hypothesis for the upper aseismic-seismic transition is that transformation of smectite to illite at ∼100–150°C triggers a change from rate-strengthening frictional behavior that allows only stable sliding, to rate weakening behavior considered a prere
Authors
Demian M. Saffer, David A. Lockner, Alex McKiernan
The role of photogeologic mapping in traverse planning: Lessons from DRATS 2010 activities
We produced a 1:24,000 scale photogeologic map of the Desert Research and Technology Studies (DRATS) 2010 simulated lunar mission traverse area and surrounding environments located within the northeastern part of the San Francisco Volcanic Field (SFVF), north-central Arizona. To mimic an exploratory mission, we approached the region “blindly” by rejecting prior knowledge or preconceived notions of
Authors
James A. Skinner, Corey M. Fortezzo
Curiosity's Mars Hand Lens Imager (MAHLI) investigation
The Mars Science Laboratory (MSL) Mars Hand Lens Imager (MAHLI) investigation will use a 2-megapixel color camera with a focusable macro lens aboard the rover, Curiosity, to investigate the stratigraphy and grain-scale texture, structure, mineralogy, and morphology of geologic materials in northwestern Gale crater. Of particular interest is the stratigraphic record of a ?5 km thick layered rock se
Authors
Kenneth S. Edgett, R. Aileen Yingst, Michael A. Ravine, Michael A. Caplinger, Justin N. Maki, F. Tony Ghaemi, Jacob A. Schaffner, James F. Bell, Laurence J. Edwards, Kenneth E. Herkenhoff, Ezat Heydari, Linda C. Kah, Mark T. Lemmon, Michelle E. Minitti, Timothy S. Olson, Timothy J. Parker, Scott K. Rowland, Juergen Schieber, Robert J. Sullivan, Dawn Y. Sumner, Peter C. Thomas, Elsa H. Jensen, John J. Simmonds, Aaron J. Sengstacken, Reg G. Wilson, Walter Goetz
Tracking lava flow emplacement on the east rift zone of Kilauea, Hawai’i with synthetic aperture radar (SAR) coherence
Lava flow mapping is both an essential component of volcano monitoring and a valuable tool for investigating lava flow behavior. Although maps are traditionally created through field surveys, remote sensing allows an extraordinary view of active lava flows while avoiding the difficulties of mapping on location. Synthetic aperture radar (SAR) imagery, in particular, can detect changes in a flow fie
Authors
Hannah R. Dietterich, Michael P. Poland, David Schmidt, Katharine V. Cashman, David R. Sherrod, Arkin Tapia Espinosa
Selection of the Mars Science Laboratory landing site
The selection of Gale crater as the Mars Science Laboratory landing site took over five years, involved broad participation of the science community via five open workshops, and narrowed an initial >50 sites (25 by 20 km) to four finalists (Eberswalde, Gale, Holden and Mawrth) based on science and safety. Engineering constraints important to the selection included: (1) latitude (±30°) for thermal
Authors
M. Golombek, J. Grant, D. Kipp, A. Vasavada, Randolph L. Kirk, Robin L. Fergason, P. Bellutta, F. Calef, K. Larsen, Y. Katayama, A. Huertas, R. Beyer, A. Chen, T. Parker, B. Pollard, S. Lee, R. Hoover, H. Sladek, J. Grotzinger, R. Welch, E. Noe Dobrea, J. Michalski, M. Watkins
Peninsular terrane basement ages recorded by Paleozoic and Paleoproterozoic zircon in gabbro xenoliths and andesite from Redoubt volcano, Alaska
Historically Sactive Redoubt volcano is an Aleutian arc basalt-to-dacite cone constructed upon the Jurassic–Early Tertiary Alaska–Aleutian Range batholith. The batholith intrudes the Peninsular tectonostratigraphic terrane, which is considered to have developed on oceanic basement and to have accreted to North America, possibly in Late Jurassic time. Xenoliths in Redoubt magmas have been thought t
Authors
Charles R. Bacon, Jorge A. Vazquez, Joseph L. Wooden
Post-wildfire wind erosion in and around the Idaho National Laboratory Site
Wind erosion following large wildfires on and around the INL Site is a recurrent threat to human health and safety, DOE operations and trafficability, and ecological and hydrological condition of the INL Site and down-wind landscapes. Causes and consequences of wind erosion are mainly known from warm deserts (e.g., Southwest U.S.), dunefields, and croplands, and some but not all findings are trans
Authors
Matthew J. Germino
Do aftershock probabilities decay with time?
So, do aftershock probabilities decay with time? Consider a thought experiment in which we are at the time of the mainshock and ask how many aftershocks will occur a day, week, month, year, or even a century from now. First we must decide how large a window to use around each point in time. Let's assume that, as we go further into the future, we are asking a less precise question. Perhaps a day fr
Authors
Andrew J. Michael