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Publications

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Faunal and stable isotopic analyses of benthic foraminifera from the Southeast Seep on Kimki Ridge offshore southern California, USA

We investigated the benthic foraminiferal faunal and stable carbon and oxygen isotopic composition of a 15-cm push core (NA075-092b) obtained on a Telepresence-Enabled cruise to the Southeast Seep on Kimki Ridge offshore southern California. The seep core was taken at a depth of 973 m in the vicinity of a Beggiatoa bacterial mat and vesicomyid clams (Calyptogena) and compared to previously publish
Authors
Mary McGann, James E. Conrad

Final Mimas and Enceladus atlases derived from Cassini-ISS images

The Imaging Science Subsystem (ISS) on-board Cassini took a few high-resolution images of the icy Saturnian satellites Mimas and Enceladus over the last seven years of the Cassini mission during non-targeted flybys. We used the new Mimas images to improve the existing semi-controlled mosaic of Mimas. A new controlled Enceladus mosaic was published recently (Bland et al., 2015; Bland et al. in prep
Authors
Thomas Roatsch, E. Kersten, K.-D. Matz, Michael T. Bland, Tammy L. Becker, Gerald Wesley Patterson, C. Porco

Remotely sensing the morphometrics and dynamics of a cold region dune field using historical aerial photography and airborne LiDAR data

This study uses an airborne Light Detection and Ranging (LiDAR) survey, historical aerial photography and historical climate data to describe the character and dynamics of the Nogahabara Sand Dunes, a sub-Arctic dune field in interior Alaska’s discontinuous permafrost zone. The Nogahabara Sand Dunes consist of a 43-km2 area of active transverse and barchanoid dunes within a 3200-km2 area of vegeta
Authors
Carson Baughman, Benjamin M. Jones, Karin L. Bodony, Daniel H. Mann, Christopher F. Larsen, Emily A. Himmelstoss, Jeremy Smith

The thermophysical properties of the Bagnold Dunes, Mars: Ground truthing orbital data

We compare the thermophysical properties and particle sizes derived from the Mars Science Laboratory rover's Ground Temperature Sensor of the Bagnold dunes, specifically Namib dune, to those derived orbitally from Thermal Emission Imaging System, ultimately linking these measurements to ground truth particle sizes determined from Mars Hand Lens Imager images. In general, we find that all three dat
Authors
Christopher S. Edwards, Sylvain Piqueux, Victoria E. Hamilton, Robin L. Fergason, Kenneth E. Herkenhoff, Ashwin R. Vasavada, Kristen A. Bennett, Leah Sacks, Kevin Lewis, Michael D. Smith

Downhole physical property-based description of a gas hydrate petroleum system in NGHP-02 Area C: A channel, levee, fan complex in the Krishna-Godavari Basin offshore eastern India

India’s second National Gas Hydrate Program expedition, NGHP-02, collected logging while drilling and sediment core data in Area C offshore eastern India, to investigate controls on the distribution and peak saturations of methane gas hydrate occurrences in buried channel, levee and fan deposits. Physical property results are presented here for the four Area C coring sites: NGHP-02-07, targeting
Authors
William F. Waite, Junbong Jang, Timothy S. Collett, Ronish Kumar

The limits of earthquake early warning: Timeliness of ground motion estimates

The basic physics of earthquakes is such that strong ground motion cannot be expected from an earthquake unless the earthquake itself is very close or has grown to be very large. We use simple seismological relationships to calculate the minimum time that must elapse before such ground motion can be expected at a distance from the earthquake, assuming that the earthquake magnitude is not predictab
Authors
Sarah E. Minson, Men-Andrin Meier, Annemarie S. Baltay, Thomas C. Hanks, Elizabeth S. Cochran

An updated stress map of the continental U.S. reveals heterogeneous intraplate stress

Knowledge of the state of stress in the Earth’s crust is key to understanding the forces and processes responsible for earthquakes. Historically, low rates of natural seismicity in the central and eastern United States have complicated efforts to understand intraplate stress, but recent improvements in seismic networks and the spread of human-induced seismicity have greatly improved data coverage.
Authors
Will Levandowski, Robert B Hermann, Richard W. Briggs, Oliver S. Boyd, Ryan D. Gold

Slope failure and mass transport processes along the Queen Charlotte Fault, southeastern Alaska

The Queen Charlotte Fault defines the Pacific–North America transform plate boundary in western Canada and southeastern Alaska for c. 900 km. The entire length of the fault is submerged along a continental margin dominated by Quaternary glacial processes, yet the geomorphology along the margin has never been systematically examined due to the absence of high-resolution seafloor mapping data. Hence

Authors
Daniel Brothers, Brian D. Andrews, Maureen A. L. Walton, H. Gary Greene, J. Vaughn Barrie, Nathaniel C. Miller, Uri S. ten Brink, Amy E. East, Peter J. Haeussler, Jared W. Kluesner, James E. Conrad

Integrating real-time subsurface hydrologic monitoring with empirical rainfall thresholds to improve landslide early warning

Early warning for rainfall-induced shallow landsliding can help reduce fatalities and economic losses. Although these commonly occurring landslides are typically triggered by subsurface hydrological processes, most early warning criteria rely exclusively on empirical rainfall thresholds and other indirect proxies for subsurface wetness. We explore the utility of explicitly accounting for anteceden
Authors
Benjamin B. Mirus, Rachel E. Becker, Rex L. Baum, Joel B. Smith

Seismicity in the Challis, Idaho region, January 2014 - May 2017: Late aftershocks of the 1983 Ms 7.3 Borah Peak earthquake

In April 2014, after about 20 yrs of relatively low seismicity, an energetic earthquake sequence (maximum ML 4.8) began 25–30 km northwest of the 1983 Ms 7.3 Borah Peak earthquake rupture area near the town of Challis, Idaho. This sequence ended in the fall of 2014, but in January 2015, a second energetic sequence (maximum ML 5.0) began about 20 km to the southeast. Modest seismicity has continued
Authors
Guanning Pang, Keith D. Koper, Michael C. Stickney, James C. Pechmann, Relu Burlacu, Kristine L. Pankow, Suzette Payne, Harley M. Benz

Application of microtremor horizontal-to-vertical spectral ratio (MHVSR) analysis for site characterization: State of the art

Nakamura (Q Rep Railway Tech Res Inst 30:25–33, 1989) popularized the application of the horizontal-to-vertical spectral ratio (HVSR) analysis of microtremor (seismic noise or ambient vibration) recordings to estimate the predominant frequency and amplification factor of earthquake shaking. During the following quarter century, popularity in the microtremor HVSR (MHVSR) method grew; studies have v
Authors
S. Molnar, J. F. Cassidy, S. Castellaro, C. Cornou, H. Crow, J. A. Hunter, S. Matsushima, F. J. Sanchez-Sesma, Alan Yong

Strong variation in weathering of layered rock maintains hillslope‐scale strength under high precipitation

The evolution of volcanic landscapes and their landslide potential are both dependent upon the weathering of layered volcanic rock sequences. We characterize critical zone structure using shallow seismic Vp and Vs profiles and vertical exposures of rock across a basaltic climosequence on Kohala peninsula, Hawai’i, and exploit the dramatic gradient in mean annual precipitation (MAP) across the peni
Authors
Jennifer Von Voigtlander, Marin K. Clark, Dimitrios Zekkos, William W. Greenwood, Suzanne P. Anderson, Robert S. Anderson, Jonathan W. Godt