Publications
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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
Operational nowcasting of electron flux levels in the outer zone of Earth's radiation belt
We describe a lightweight, accurate nowcasting model for electron flux levels measured by the Van Allen probes. Largely motivated by Rigler et al. (2004, https://doi.org/10.1029/2003SW000036), we turn to a time‐varying linear filter of previous flux levels and Kp. We train and test this model on data gathered from the 2.10 MeV channel of the Relativistic Electron‐Proton Telescope sensor onboard th
Authors
Tim Coleman, James P. McCollough, Shawn L. Young, E. Joshua Rigler
Estimating fluvial discharges coincident with 21st century coastal storms modeled with CoSMoS
On the open coast, flooding is largely driven by tides, storm surge, waves, and in areas near coastal inlets, the magnitude and co-occurrence of high fluvial discharges. Statistical methods are typically used to estimate the individual probability of coastal storm and fluvial discharge occurrences for use in sophisticated flood hazard models. A challenge arises when considering possible future cli
Authors
Li H. Erikson, Andrea C. O'Neill, Patrick L. Barnard
Interaction between hydraulic fracture and a preexisting fracture under triaxial stress conditions
Enhanced reservoir connectivity generally requires maximizing the intersection between hydraulic fracture (HF) and preexisting underground natural fractures (NF), while having the hydraulic fracture cross the natural fractures (and not arrest). We have studied the interaction between a hydraulic fracture and a polished saw-cut fault. The experiments include a hydraulic fracture initiating from a p
Authors
Saied Mighani, David A. Lockner, Brian D. Kilgore, Farrokh Sheibani, Brian Evans