Publications
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Amplification of postwildfire peak flow by debris
In burned steeplands, the peak depth and discharge of postwildfire runoff can substantially increase from the addition of debris. Yet methods to estimate the increase over water flow are lacking. We quantified the potential amplification of peak stage and discharge using video observations of postwildfire runoff, compiled data on postwildfire peak flow (Qp), and a physically based model. Compariso
Authors
Jason W. Kean, Luke McGuire, Francis K. Rengers, Joel B. Smith, Dennis M. Staley
Coseismic slip and early afterslip of the 2015 Illapel, Chile, earthquake: Implications for frictional heterogeneity and coastal uplift
Great subduction earthquakes are thought to rupture portions of the megathrust, where interseismic coupling is high and velocity-weakening frictional behavior is dominant, releasing elastic deformation accrued over a seismic cycle. Conversely, postseismic afterslip is assumed to occur primarily in regions of velocity-strengthening frictional characteristics that may correlate with lower interseism
Authors
William D. Barnhart, Jessica R. Murray, Richard W. Briggs, Francisco Gomez, Charles P. J. Miles, Jerry L. Svarc, Sebástian Riquelme, Bryan J. Stressler
Responses of a tall building in Los Angeles, California as inferred from local and distant earthquakes
Increasing inventory of tall buildings in the United States and elsewhere may be subjected to motions generated by near and far seismic sources that cause long-period effects. Multiple sets of records that exhibited such effects were retrieved from tall buildings in Tokyo and Osaka ~ 350 km and 770 km from the epicenter of the 2011 Tohoku earthquake. In California, very few tall buildings have bee
Authors
Mehmet Çelebi, Hasan Ulusoy, Nori Nakata
Comparisons between vs30 and spectral response for 30 sites in Newcastle, Australia from collocated seismic cone penetrometer, active- and passive-source vs data
Although the time‐averaged shear‐wave velocity down to 30 m depth (VS30) can be a proxy for estimating earthquake ground‐motion amplification, significant controversy exists about its limitations when used as a single parameter for the prediction of amplification. To examine this question in absence of relevant strong‐motion records, we use a range of different methods to measure the shear‐wave ve
Authors
Theodora Volti, David Burbidge, Clive Collins, Michael W. Asten, Jackson K. Odum, William J. Stephenson, Chris Pascal, Josef Holzschuh
The influence of vegetation cover on debris-flow density during an extreme rainfall in the northern Colorado Front Range
We explored regional influences on debris-flow initiation throughout the Colorado Front Range (Colorado, USA) by exploiting a unique data set of more than 1100 debris flows that initiated during a 5 day rainstorm in 2013. Using geospatial data, we examined the influence of rain, hillslope angle, hillslope aspect, and vegetation density on debris-flow initiation. In particular we used a greenness i
Authors
Francis K. Rengers, Luke McGuire, Jeffrey A. Coe, Jason W. Kean, Rex L. Baum, Dennis M. Staley, Jonathan W. Godt
Complex explosive volcanic activity on the Moon within Oppenheimer crater
Oppenheimer Crater is a floor-fractured crater located within the South Pole-Aitken basin on the Moon, and exhibits more than a dozen localized pyroclastic deposits associated with the fractures. Localized pyroclastic volcanism on the Moon is thought to form as a result of intermittently explosive Vulcanian eruptions under low effusion rates, in contrast to the higher-effusion rate, Hawaiian-style
Authors
Kristen A Bennett, Briony H. N. Horgan, Lisa R. Gaddis, Benjamin T Greenhagen, Carlton C. Allen, Paul O. Hayne, James F. Bell, David A. Paige
ChemCam activities and discoveries during the nominal mission of the Mars Science Laboratory in Gale crater, Mars
At Gale crater, Mars, ChemCam acquired its first laser-induced breakdown spectroscopy (LIBS) target on Sol 13 of the landed portion of the mission (a Sol is a Mars day). Up to Sol 800, more than 188 000 LIBS spectra were acquired on more than 5800 points distributed over about 650 individual targets. We present a comprehensive review of ChemCam scientific accomplishments during that period, togeth
Authors
Sylvestre Maurice, Samuel M. Clegg, Roger C. Wiens, O. Gasnault, W. Rapin, O. Forni, Agnès Cousin, V. Sautter, Nicolas Mangold, L. Le Deit, Marion Nachon, Ryan Anderson, Nina Lanza, Cecile Fabre, Valerie Payre, Jeremie Lasue, Pierre-Yves Meslin, Richard A. LeVeille, Bruce Barraclough, Pierre Beck, Steven C. Bender, Gilles Berger, John C. Bridges, Nathan Bridges, Gilles Dromert, M. Darby Dyar, Raymond Francis, Jens Frydenvang, B. Gondet, Bethany L. Ehlmann, Kenneth E. Herkenhoff, Jeffrey R. Johnson, Yves Langevin, Madsen Morten B., N. Melikechi, J.-L. Lacour, Stephane Le Mouelic, Eric Lewin, Horton E. Newsom, Ann M. Ollila, Patrick Pinet, S. Schroder, Jean-Baptiste Sirven, Robert L. Tokar, M.J. Toplis, Claude d'Uston, David Vaniman, Ashwin R. Vasavada
Granitic boulder erosion caused by chaparral wildfire: Implications for cosmogenic radionuclide dating of bedrock surfaces
Rock surface erosion by wildfire is significant and widespread but has not been quantified in southern California or for chaparral ecosystems. Quantifying the surface erosion of bedrock outcrops and boulders is critical for determination of age using cosmogenic radionuclide techniques, as even modest surface erosion removes the accumulation of the cosmogenic radionuclides and causes significant un
Authors
Katherine J. Kendrick, Camille Partin, Robert C. Graham
The missing large impact craters on Ceres
Asteroids provide fundamental clues to the formation and evolution of planetesimals. Collisional models based on the depletion of the primordial main belt of asteroids predict 10–15 craters >400 km should have formed on Ceres, the largest object between Mars and Jupiter, over the last 4.55 Gyr. Likewise, an extrapolation from the asteroid Vesta would require at least 6–7 such basins. However, Cere
Authors
S. Marchi, A. Ermakov, C.A. Raymond, R.R. Fu, D.P. O'Brien, Michael T. Bland, E. Ammannito, M.C. De Sanctis, Tim Bowling, P. Schenk, J.E.C. Scully, D.L. Buczkowski, D.A. Williams, H. Hiesinger, C.T. Russell
Subsidence rates at the southern Salton Sea consistent with reservoir depletion
Space geodetic measurements from the Envisat satellite between 2003 and 2010 show that subsidence rates near the southeastern shoreline of the Salton Sea in Southern California are up to 52mmyr−1 greater than the far-field background rate. By comparing these measurements with model predictions, we find that this subsidence appears to be dominated by poroelastic contraction associated with ongoing
Authors
Andrew J. Barbour, Eileen Evans, Stephen H. Hickman, Mariana Eneva
U.S. Geological Survey Volcano Hazards Program—Assess, forecast, prepare, engage
At least 170 volcanoes in 12 States and 2 territories have erupted in the past 12,000 years and have the potential to erupt again. Consequences of eruptions from U.S. volcanoes can extend far beyond the volcano’s immediate area. Many aspects of our daily life are vulnerable to volcano hazards, including air travel, regional power generation and transmission infrastructure, interstate transportatio
Authors
Wendy K. Stovall, Aleeza M. Wilkins, Charlie Mandeville, Carolyn L. Driedger
Structure of the 1906 near-surface rupture zone of the San Andreas Fault, San Francisco Peninsula segment, near Woodside, California
High-resolution seismic-reflection and refraction images of the 1906 surface rupture zone of the San Andreas Fault near Woodside, California reveal evidence for one or more additional near-surface (within about 3 meters [m] depth) fault strands within about 25 m of the 1906 surface rupture. The 1906 surface rupture above the groundwater table (vadose zone) has been observed in paleoseismic trenche
Authors
C.M. Rosa, R. D. Catchings, M. J. Rymer, Karen Grove, M. R. Goldman