Publications
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Kelp, cobbles, and currents: Biologic reduction of coarse grain entrainment stress Kelp, cobbles, and currents: Biologic reduction of coarse grain entrainment stress
Models quantifying the onset of sediment motion do not typically account for the effect of biotic processes because they are difficult to isolate and quantify in relation to physical processes. Here we investigate an example of the interaction of kelp (Order Laminariales) and coarse sediment transport in the coastal zone, where it is possible to directly quantify and test its effect...
Authors
Claire C Masteller, Noah J Finnegan, Jonathan A. Warrick, Ian M. Miller
Artificial seismic acceleration Artificial seismic acceleration
In their 2013 paper, Bouchon, Durand, Marsan, Karabulut, 3 and Schmittbuhl (BDMKS) claim to see significant accelerating seismicity before M 6.5 interplate mainshocks, but not before intraplate mainshocks, reflecting a preparatory process before large events. We concur with the finding of BDMKS that their interplate dataset has significantly more fore- shocks than their intraplate...
Authors
Karen R. Felzer, Morgan T. Page, Andrew J. Michael
Paleoseismic evidence for late Holocene tectonic deformation along the Saddle mountain fault zone, Southeastern Olympic Peninsula, Washington Paleoseismic evidence for late Holocene tectonic deformation along the Saddle mountain fault zone, Southeastern Olympic Peninsula, Washington
Trench and wetland coring studies show that northeast‐striking strands of the Saddle Mountain fault zone ruptured the ground about 1000 years ago, generating prominent scarps. Three conspicuous subparallel fault scarps can be traced for 15 km on Light Detection and Ranging (LiDAR) imagery, traversing the foothills of the southeast Olympic Mountains: the Saddle Mountain east fault, the...
Authors
Elizabeth Barnett, Brian L. Sherrod, Jonathan F. Hughes, Harvey M. Kelsey, Jessica L. Czajkowski, Timothy J. Walsh, Trevor A. Contreras, Elizabeth R. Schermer, Robert J. Carson
Time-varying interseismic strain rates and similar seismic ruptures on the Nias-Simeulue patch of the Sunda megathrust Time-varying interseismic strain rates and similar seismic ruptures on the Nias-Simeulue patch of the Sunda megathrust
Fossil coral microatolls from fringing reefs above the great (MW 8.6) megathrust rupture of 2005 record uplift during the historically reported great earthquake of 1861. Such evidence spans nearly the entire 400-km strike length of the 2005 rupture, which was previously shown to be bounded by two persistent barriers to seismic rupture. Moreover, at sites where we have constrained the...
Authors
Aron J. Meltzner, Kerry E. Sieh, Hong-Wei Chiang, Chung-Che Wu, Louisa L.H. Tsang, Chuan-Chou Shen, Emma M. Hill, Bambang W. Suwargadi, Danny H. Natawidjaja, Belle Philibosian, Richard W. Briggs
Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review
The study of mass and energy transfer across landscapes has recently evolved to comprehensive considerations acknowledging the role of biota and humans as geomorphic agents, as well as the importance of small-scale landscape features. A contributing and supporting factor to this evolution is the emergence over the last two decades of technologies able to acquire high resolution...
Authors
Paola Passaiacquaa, Patrick Belmont, Dennis M. Staley, Jeffery Simley, J. Ramon Arrowsmith, Collin A. Bode, Christopher Crosby, Stephen DeLong, Nancy Glenn, Sara Kelly, Dimitri Lague, Harish Sangireddy, Keelin Schaffrath, David Tarboton, Thad Wasklewicz, Joseph Wheaton
Kinematics of shallow backthrusts in the Seattle fault zone, Washington State Kinematics of shallow backthrusts in the Seattle fault zone, Washington State
Near-surface thrust fault splays and antithetic backthrusts at the tips of major thrust fault systems can distribute slip across multiple shallow fault strands, complicating earthquake hazard analyses based on studies of surface faulting. The shallow expression of the fault strands forming the Seattle fault zone of Washington State shows the structural relationships and interactions...
Authors
Thomas L. Pratt, K.G. Troost, Jackson K. Odum, William J. Stephenson
Chronology and ecology of late Pleistocene megafauna in the northern Willamette Valley, Oregon 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...
Authors
Daniel M. Gilmour, Virginia L. Butler, James E. O'Connor, Edward Byrd Davis, Brendan J. Culleton, Douglas J. Kennett, Gregory W. L. Hodgins
Asteroid photometry 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...
Authors
Jian-Yang Li, Paul Helfenstein, Bonnie J. Buratti, Driss Takir, Beth Ellen Clark
The use of wavenumber normalization in computing spatially averaged coherencies (KRSPAC) of microtremor data from asymmetric arrays 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...
Authors
M.W. Asten, William J. Stephenson, Stephen H. Hartzell
High‐resolution trench photomosaics from image‐based modeling: Workflow and error analysis High‐resolution trench photomosaics from image‐based modeling: Workflow and error analysis
Photomosaics are commonly used to construct maps of paleoseismic trench exposures, but the conventional process of manually using image‐editing software is time consuming and produces undesirable artifacts and distortions. Herein, we document and evaluate the application of image‐based modeling (IBM) for creating photomosaics and 3D models of paleoseismic trench exposures, illustrated...
Authors
Nadine G. Reitman, Scott E.K. Bennett, Ryan D. Gold, Richard W. Briggs, Christopher B. DuRoss
Understanding the signature of rock coatings in laser-induced breakdown spectroscopy data 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...
Authors
Nina L. Lanza, Ann M. Ollila, Agnes 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
Thin‐ or thick‐skinned faulting in the Yakima fold and thrust belt (WA)? Constraints from kinematic modeling of the saddle mountains anticline Thin‐ or thick‐skinned faulting in the Yakima fold and thrust belt (WA)? Constraints from kinematic modeling of the saddle mountains anticline
The Yakima fold and thrust belt (YFTB) deforms the Columbia River Basalt Group flows of Washington State. The YFTB fault geometries and slip rates are crucial parameters for seismic‐hazard assessments of nearby dams and nuclear facilities, yet there are competing models for the subsurface fault geometry involving shallowly rooted versus deeply rooted fault systems. The YFTB is also...
Authors
Gabriele Casale, Thomas L. Pratt