Publications
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Conversion of wet glass to melt at lower seismogenic zone conditions: Implications for pseudotachylyte creep Conversion of wet glass to melt at lower seismogenic zone conditions: Implications for pseudotachylyte creep
Coseismic frictional melting and the production of quenched glass called pseudotachylyte is a recurring process during earthquakes. To investigate how glassy materials affect the postseismic strength and stability of faults, obsidian gouges were sheared under dry and wet conditions from 200°C to 300°C at ~150 MPa effective normal stress. Dry glass exhibited a brittle rheology at all...
Authors
Brooks P. Proctor, David A. Lockner, Jacob B. Lowenstern, Nicholas M. Beeler
3-D simulations of M9 earthquakes on the Cascadia Megathrust: Key parameters and uncertainty 3-D simulations of M9 earthquakes on the Cascadia Megathrust: Key parameters and uncertainty
Geologic and historical records indicate that the Cascadia subduction zone is capable of generating large, megathrust earthquakes up to magnitude 9. The last great Cascadia earthquake occurred in 1700, and thus there is no direct measure on the intensity of ground shaking or specific rupture parameters from seismic recordings. We use 3-D numerical simulations to generate broadband (0-10...
Authors
Erin Wirth, Arthur D. Frankel, John Vidale, Nasser A. Marafi, William J. Stephenson
Presentation and analysis of a worldwide database of earthquake-induced landslide inventories Presentation and analysis of a worldwide database of earthquake-induced landslide inventories
Earthquake-induced landslide (EQIL) inventories are essential tools to extend our knowledge of the relationship between earthquakes and the landslides they can trigger. Regrettably, such inventories are difficult to generate and therefore scarce, and the available ones differ in terms of their quality and level of completeness. Moreover, access to existing EQIL inventories is currently...
Authors
Hakan Tanyas, Cees J. van Westen, Kate E. Allstadt, M. Anna Nowicki Jessee, Tolga Gorum, Randall W. Jibson, Jonathan W. Godt, Hiroshi P. Sato, Robert G. Schmitt, Odin Marc, Niels Hovius
Holocene earthquakes of magnitude 7 during westward escape of the Olympic Mountains, Washington Holocene earthquakes of magnitude 7 during westward escape of the Olympic Mountains, Washington
The Lake Creek–Boundary Creek fault, previously mapped in Miocene bedrock as an oblique thrust on the north flank of the Olympic Mountains, poses a significant earthquake hazard. Mapping using 2015 light detection and ranging (lidar) confirms 2004 lidar mapping of postglacial (≥14 km along a splay fault, the Sadie Creek fault, west of Lake Crescent. Scarp morphology suggests repeated...
Authors
Alan R. Nelson, Stephen Personius, Ray E. Wells, Elizabeth R. Schermer, Lee-Ann Bradley, Jason Buck, Nadine G. Reitman
Refining fault slip rates using multiple displaced terrace risers-An example from the Honey Lake fault, NE California, USA Refining fault slip rates using multiple displaced terrace risers-An example from the Honey Lake fault, NE California, USA
Faulted terrace risers are semi-planar features commonly used to constrain Quaternary slip rates along strike-slip faults. These landforms are difficult to date directly and therefore their ages are commonly bracketed by age estimates of the adjacent upper and lower terrace surfaces. However, substantial differences in the ages of the upper and lower terrace surfaces (a factor of 2.4...
Authors
Ryan D. Gold, Richard W. Briggs, Anthony J. Crone, Christopher DuRoss
Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution Pitted terrains on (1) Ceres and implications for shallow subsurface volatile distribution
Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials
Authors
H.G. Sizemore, Thomas Platz, Norbert Schorghofer, Thomas Prettyman, Maria Christina De Sanctis, David A. Crown, Nico Schmedemann, Andeas Nessemann, Thomas Kneissl, Simone Marchi, Paul M. Schenk, Michael T. Bland, B.E. Schmidt, Kynan H.G. Hughson, F. Tosi, F Zambon, S.C. Mest, R.A. Yingst, D.A. Williams, C.T. Russell, C.A. Raymond
Results of hydrologic monitoring of a landslide-prone hillslope in Portland’s West Hills, Oregon, 2006–2017 Results of hydrologic monitoring of a landslide-prone hillslope in Portland’s West Hills, Oregon, 2006–2017
The West Hills of Portland, in the southern Tualatin Mountains, trend northwest along the west side of Portland, Oregon. These silt-mantled mountains receive significant wet-season precipitation and are prone to sliding during wet conditions, occasionally resulting in property damage or casualties. In an effort to develop a baseline for interpretive analysis of the groundwater response...
Authors
Joel B. Smith, Jonathan W. Godt, Rex L. Baum, Jeffrey A. Coe, William L. Ellis, Eric S. Jones, Scott F. Burns
Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence
Landslides typically alter hillslope topography, but may also change the hydrologic connectivity and subsurface water-storage dynamics. In settings where mobile materials are not completely evacuated from steep slopes, influences of landslide disturbances on hillslope hydrology and susceptibility to subsequent failures remain poorly characterized. Since landslides often recur at the site...
Authors
Benjamin B. Mirus, Joel B. Smith, Rex L. Baum
Selection of the InSight landing site Selection of the InSight landing site
The selection of the Discovery Program InSight landing site took over four years from initial identification of possible areas that met engineering constraints, to downselection via targeted data from orbiters (especially Mars Reconnaissance Orbiter (MRO) Context Camera (CTX) and High-Resolution Imaging Science Experiment (HiRISE) images), to selection and certification via sophisticated...
Authors
M. Golombek, D. Kipp, N. Warner, Ingrid J. Daubar, Robin L. Fergason, Randolph L. Kirk, R. Beyer, A. Huertas, Sylvain Piqueux, N.E. Putzig, B.A. Campbell, G. A. Morgan, C. Charalambous, W. T. Pike, K. Gwinner, F. Calef, D. Kass, M. A. Mischna, J. Ashley, C. Bloom, N. Wigton, T. Hare, C. Schwartz, H. Gengl, L. Redmond, M. Trautman, J. Sweeney, C. Grima, I. B. Smith, E. Sklyanskiy, M. Lisano, J. Benardini, S.E. Smrekar, P. Lognonne, W. B. Banerdt
The Mars Science Laboratory Curiosity rover Mastcam instruments: Preflight and in-flight calibration, validation, and data archiving The Mars Science Laboratory Curiosity rover Mastcam instruments: Preflight and in-flight calibration, validation, and data archiving
The NASA Curiosity rover Mast Camera (Mastcam) system is a pair of fixed-focal length, multispectral, color CCD imagers mounted ~2 m above the surface on the rover's remote sensing mast, along with associated electronics and an onboard calibration target. The left Mastcam (M-34) has a 34 mm focal length, an instantaneous field of view (IFOV) of 0.22 mrad, and a FOV of 20° × 15° over the...
Authors
James F. Bell, A. Godber, S. McNair, M.A. Caplinger, J.N. Maki, M. T. Lemmon, J. Van Beek, M.C. Malin, D. Wellington, K.M. Kinch, M.B. Madsen, C. Hardgrove, M.A. Ravine, E. Jensen, D. Harker, Ryan B. Anderson, Kenneth E. Herkenhoff, R.V. Morris, E. Cisneros, R. G. Deen
Viscous relaxation of Ganymede's impact craters: Constraints on heat flux Viscous relaxation of Ganymede's impact craters: Constraints on heat flux
Measurement of crater depths in Ganymede’s dark terrain have revealed substantial numbers of unusually shallow craters indicative of viscous relaxation [see companion paper: Singer, K.N., Schenk, P. M., Bland, M.T., McKinnon, W.B., (2017). Relaxed impact craters on Ganymede: Regional variations and high heat flow. Icarus, submitted]. These viscously relaxed craters provide insight into...
Authors
Michael T. Bland, Kelsi N. Singer, William B. McKinnon, Paul M. Schenk
In situ detection of boron by ChemCam on Mars In situ detection of boron by ChemCam on Mars
We report the first in situ detection of boron on Mars. Boron has been detected in Gale crater at levels
Authors
Patrick J. Gasda, Ethan B. Haldeman, Roger C. Wiens, William Rapin, Thomas F. Bristow, John C. Bridges, Susanne P. Schwenzer, Benton C. Clark, Kenneth E. Herkenhoff, Jens Frydenvang, Nina L. Lanza, Sylvestre Maurice, Samuel M. Clegg, Dorothea M. Delapp, Veronica L. Sanford, Madeleine R. Bodine, Rhonda McInroy