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Paleoseismology of the Denali fault system at the Schist Creek site, central Alaska

Two hand-dug trenches at the Schist Creek site on the Denali fault system in central Alaska exposed evidence of four surface-rupturing earthquakes on the basis of upward terminations of fault strands and at least one buried, scarp-derived colluvial wedge. Limited radiocarbon ages provide some constraints on times of the ruptures. The youngest rupture (PE1) likely occurred about 200–400 years ago,
Authors
Stephen F. Personius, Anthony J. Crone, Patricia A.C. Burns, Ned Rozell

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. Kelp is ubiqu
Authors
Claire C Masteller, Noah J Finnegan, Jonathan Warrick, Ian M. Miller

Context of ancient aqueous environments on Mars from in situ geologic mapping at Endeavour Crater

Using the Mars Exploration Rover Opportunity, we have compiled one of the first field geologic maps on Mars while traversing the Noachian terrain along the rim of the 22 km diameter Endeavour Crater (Latitude −2°16′33″, Longitude −5°10′51″). In situ mapping of the petrographic, elemental, structural, and stratigraphic characteristics of outcrops and rocks distinguishes four mappable bedrock lithol
Authors
L.S. Crumpler, R. E. Arvidson, J. Bell, B. C. Clark, B. A. Cohen, W. H. Farrand, Ralf Gellert, M. Golombek, J. A. Grant, E. Guinness, Kenneth E. Herkenhoff, J. R. Johnson, B. Jolliff, D. W. Ming, D. W. Mittlefehldt, T. Parker, J. W. Rice, S. W. Squyres, R. Sullivan, A. S. Yen

U.S. States and Territories National Tsunami Hazard Assessment: Historical record and sources for waves – Update

The first U.S. Tsunami Hazard Assessment (Dunbar and Weaver, 2008) was prepared at the request of the National Tsunami Hazard Mitigation Program (NTHMP). The NTHMP is a partnership formed between federal and state agencies to reduce the impact of tsunamis through hazard assessment, warning guidance, and mitigation. The assessment was conducted in response to a 2005 joint report by the Sub-Committe
Authors
Paula K. Dunbar, Craig S. Weaver

Rapid damage mapping for the 2015 M7.8 Gorkha earthquake using synthetic aperture radar data from COSMO-SkyMed and ALOS-2 satellites

The 25 April 2015 Mw 7.8 Gorkha earthquake caused more than 8000 fatalities and widespread building damage in central Nepal. The Italian Space Agency’s COSMO–SkyMed Synthetic Aperture Radar (SAR) satellite acquired data over Kathmandu area four days after the earthquake and the Japan Aerospace Exploration Agency’s Advanced Land Observing Satellite-2 SAR satellite for larger area nine days after th
Authors
Sang-Ho Yun, Kenneth W. Hudnut, Susan Owen, Frank Webb, Mark Simons, Patrizia Sacco, Eric Gurrola, Gerald Manipon, Cunren Liang, Eric Fielding, Pietro Milillo, Hook Hua, Alessandro Coletta

Double point source W-phase inversion: Real-time implementation and automated model selection

Rapid and accurate characterization of an earthquake source is an extremely important and ever evolving field of research. Within this field, source inversion of the W-phase has recently been shown to be an effective technique, which can be efficiently implemented in real-time. An extension to the W-phase source inversion is presented in which two point sources are derived to better characterize c
Authors
Jennifer Nealy, Gavin P. Hayes

The 2014 Mw6.1 South Napa Earthquake: A unilateral rupture with shallow asperity and rapid afterslip

The Mw6.1 South Napa earthquake occurred near Napa, California on August 24, 2014 (UTC), and was the largest inland earthquake in Northern California since the 1989 Mw6.9 Loma Prieta earthquake. The first report of the earthquake from the Northern California Earthquake Data Center (NCEDC) indicates a hypocentral depth of 11.0km with longitude and latitude of (122.3105°W, 38.217°N). Surface rupture
Authors
Shengji Wei, Sylvain Barbot, Robert Graves, James J. Lienkaemper, Teng Wang, Kenneth W. Hudnut, Yuning Fu, Don Helmberger

Collapse risk of buildings in the Pacific Northwest region due to subduction earthquakes

Subduction earthquakes similar to the 2011 Japan and 2010 Chile events will occur in the future in the Cascadia subduction zone in the Pacific Northwest. In this paper, nonlinear dynamic analyses are carried out on 24 buildings designed according to outdated and modern building codes for the cities of Seattle, Washington, and Portland, Oregon. The results indicate that the median collapse capacity
Authors
Meera Raghunandan, Abbie B. Liel, Nicolas Luco

Spatial-temporal variation of low-frequency earthquake bursts near Parkfield, California

Tectonic tremor (TT) and low-frequency earthquakes (LFEs) have been found in the deeper crust of various tectonic environments globally in the last decade. The spatial-temporal behaviour of LFEs provides insight into deep fault zone processes. In this study, we examine recurrence times from a 12-yr catalogue of 88 LFE families with ∼730 000 LFEs in the vicinity of the Parkfield section of the San
Authors
Chunquan Wu, Robert Guyer, David R. Shelly, D. Trugman, William Frank, Joan S. Gomberg, P. Johnson

Geologic setting of the proposed Fallon FORGE Site, Nevada: Suitability for EGS research and development

The proposed Fallon FORGE site lies within and adjacent to the Naval Air Station Fallon (NASF) directly southeast of the town of Fallon, Nevada, within the large basin of the Carson Sink in west-central Nevada. The site is located on two parcels that include land owned by the NASF and leased and owned by Ormat Nevada, Inc. The Carson Sink in the vicinity of the Fallon site is covered by Quaternary
Authors
James E. Faulds, Douglas Blankenship, Nicholas H. Hinz, Andrew Sabin, Josh Nordquist, Stephen H. Hickman, Jonathan M.G. Glen, Mack Kennedy, Drew Siler, Ann Robinson-Tait, Colin F. Williams, Peter Drakos, Wendy M. Calvin

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 dataset; however
Authors
Karen R. Felzer, Morgan T. Page, Andrew J. Michael

Analysis and selection of magnitude relations for the Working Group on Utah Earthquake Probabilities

Prior to calculating time-independent and -dependent earthquake probabilities for faults in the Wasatch Front region, the Working Group on Utah Earthquake Probabilities (WGUEP) updated a seismic-source model for the region (Wong and others, 2014) and evaluated 19 historical regressions on earthquake magnitude (M). These regressions relate M to fault parameters for historical surface-faulting earth
Authors
Christopher DuRoss, Susan Olig, David Schwartz