Publications
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Sparse subsurface radar reflectors in Hellas Planitia, Mars
Geomorphological features potentially related to subsurface ice, such as scalloped depressions, expanded craters, pedestal craters, and banded terrain, are present in and around Hellas Planitia, Mars. We present a radar survey of the region using the Shallow Radar (SHARAD) instrument on board the Mars Reconnaissance Orbiter (MRO) to identify candidate subsurface reflectors that may be due to the p
Authors
Claire W Cook, Ali M Bramson, Shane Byrne, John W Holt, Michael S Christoffersen, Donna Viola, Colin M. Dundas, Timothy A Goudge
Geometric and material variability influences stress states relevant to coastal permafrost bluff failure
Scientific knowledge and engineering tools for predicting coastal erosion are largely confined to temperate climate zones that are dominated by non-cohesive sediments. The pattern of erosion exhibited by the ice-bonded permafrost bluffs in Arctic Alaska, however, is not well explained by these tools. Investigation of the oceanographic, thermal, and mechanical processes that are relevant to permafr
Authors
Matthew A. Thomas, Alejandro Mota, Benjamin M. Jones, R. Charles Choens, Jennifer M. Frederick, Diana L. Bull
Aseismic transient slip on the Gofar transform fault, East Pacific Rise
Oceanic transform faults display a unique combination of seismic and aseismic slip behavior, including a large globally averaged seismic deficit, and the local occurrence of repeating magnitude (M) ∼6∼6 earthquakes with abundant foreshocks and seismic swarms, as on the Gofar transform of the East Pacific Rise and the Blanco Ridge in the northeast Pacific Ocean. However, the underlying mechanisms t
Authors
Yajing Liu, Jeffrey McGuire, Mark Behn
The influence of frequency and duration of seismic ground motion on the size of triggered landslides—A regional view
Observation, theory, and intuition all suggest that larger earthquakes should trigger larger landslides. Many factors could contribute to this, including depth-dependent shear strength or non-linearity of ground motion in soils and rock, but we hypothesize that the key characteristics of large earthquakes causing this phenomenon are (in addition to magnitude) the frequency and duration of the stro
Authors
Randall W. Jibson, Hakan Tanyaş
2018 U.S. Geological Survey–California Geological Survey fault-imaging surveys across the Hollywood and Santa Monica Faults, Los Angeles County, California
We acquired multiple types of seismic data across the Hollywood Fault in Hollywood, Calif., and the Santa Monica Fault in Beverly Hills, Calif., in May and June 2018. On the basis of our data, we infer near-surface locations of various traces of these faults.From two separate profiles across the Hollywood Fault, we evaluated multiple seismic datasets and models, including guided-wave data, tomogra
Authors
Rufus D. Catchings, Janis Hernandez, Mark R. Goldman, Joanne H. Chan, Robert R. Sickler, Brian Olson, Coyn J. Criley
The Mars Global Digital Dune Database (MGD3): Composition and stability
We present an expansion to the Mars Global Digital Dune Database (MGD3) describing 1) bulk dune field composition determined by fitting a mineral spectral library to Thermal Emission Spectra (TES) data, and 2) a morphologic stability index that measures the degree of non-aeolian modification that has eroded and stabilized each dune field. This paper describes results for these two components, prov
Authors
Lori K. Fenton, Amber Gullikson, Rosalyn Hayward, Heather Charles, Timothy N. Titus
Types and areal distribution of ground failure associated with the 2019 Ridgecrest, California, earthquake sequence
The July 2019 Ridgecrest, California, earthquake sequence included the largest earthquake (M 7.1) to strike the conterminous United States in the past 20 yr. To characterize the types, numbers, and areal distributions of different types of ground failure (landslides, liquefaction, and ground cracking), I conducted a field investigation of ground failure triggered by the sequence around the periphe
Authors
Randall W. Jibson
The future of landslides’ past—A framework for assessing consecutive landsliding systems
Landslides often happen where they have already occurred in the past. The potential of landslides to reduce or enhance conditions for further landsliding has long been recognized and has often been reported, but the mechanisms and spatial and temporal scales of these processes have previously received little specific attention. Despite a preponderance of qualitative and anecdotal evidence, there h
Authors
A. Temme, F. Guzzetti, J. Samia, Benjamin B. Mirus
Risk-targeted alternatives to deterministic ground motion caps in U.S. seismic provisions
Since their inception over 20 years ago, the maximum considered earthquake ground motion maps in U.S. building codes have capped probabilistic values with deterministic ground motions from characteristic earthquakes on known active faults. This practice has increasingly been called into question both because of spatially non-uniform risk levels that are produced (risk being higher mainly in coasta
Authors
Jonathan P. Stewart, Nicolas Luco, John D Hooper, C. B. Crouse
Predicting the floods that follow the flames
No abstract available.
Authors
Jonathan J Gourley, Humberto Vergara, Ami Arthur, Robert A III Clark, Dennis M. Staley, John Fulton, Laura A. Hempel, David C. Goodrich, Katherine Rowden, Peter R. Robichaud
Lessons learned from monitoring of turbidity currents and guidance for future platform designs
Turbidity currents transport globally significant volumes of sediment and organic carbon into the deep-sea and pose a hazard to critical infrastructure. Despite advances in technology, their powerful nature often damages expensive instruments placed in their path. These challenges mean that turbidity currents have only been measured in a few locations worldwide, in relatively shallow water depths
Authors
Michael Clare, D. Gwyn Lintern, Kurt J. Rosenberger, John Hughes Clarke, Charles K. Paull, Roberto Gwiazda, Matthieu J.B. Cartigny, Peter J. Talling, Daniel Perara, Jingping Xu, Daniel Parsons, Ricardo Silva Jacinto, Ronan Apprioual
Coseismic and post-seismic gravity disturbance induced by seismic sources using a 2.5-D spectral element method
I present a prescription for computing free-air coseismic and post-seismic gravity changes induced by seismic sources in a viscoelastic earth model. I assume a spherical earth geometry and a 2.5-D calculation, that is, 3-D motions that satisfy the equations of quasi-static equilibrium on a 2-D viscoelastic structure. The prescription permits application to regional gravity computations where a 2-D
Authors
Fred Pollitz