Publications
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The composition of Io
Io is unlike any other body in the Solar System making questions about its chemical composition especially interesting and challenging. This chapter examines the many different, but frustratingly indirect, constraints we have on the bulk composition of this restless moon. A detailed consideration of Io’s lavas is used to illustrate how decades of research have bounded, but not pinned down, the che
Authors
Laszlo P. Kestay, Terry-Ann Suer
Assessment of lunar resource exploration in 2022
The idea of mining the Moon, once purely science-fiction, is now on the verge of becoming reality. Taking advantage of the resources on the Moon is part of the plans of many nations and some enterprising commercial entities; demonstrating in-situ (in place) resource utilization near the lunar south pole is an explicit goal of the United States’ Artemis program. Economic extraction and sustainable
Authors
Laszlo P. Keszthelyi, Joshua A. Coyan, Kristen A. Bennett, Lillian R. Ostrach, Lisa R. Gaddis, Travis S. J. Gabriel, Justin Hagerty
Quantification of geodetic strain rate uncertainties and implications for seismic hazard estimates
Geodetic velocity data provide first-order constraints on crustal surface strain rates, which in turn are linked to seismic hazard. Estimating the 2-D surface strain tensor everywhere requires knowledge of the surface velocity field everywhere, while geodetic data such as Global Navigation Satellite System (GNSS) only have spatially scattered measurements on the surface of the Earth. To use these
Authors
Jeremy Maurer, Kathryn Zerbe Materna
Incorporating uncertainty in susceptibility criteria into probabilistic liquefaction hazard analysis
Most conventional approaches for assessing liquefaction triggering hazards generally rely on simplified procedures that involve identifying liquefaction susceptible layers and calculating a factor of safety against liquefaction (FSL) in each layer. Such procedures utilize deterministic semi-empirical models for standard penetration test (SPT), cone penetrometer test (CPT), or shear wave velocity (
Authors
Andrew James Makdisi
Constraints on the composition and thermal structure of Ariel’s icy crust as inferred from its largest observed impact crater
The large graben-like troughs and smooth plains visible on the surface of Ariel are indicative of a period of high heat flow in the Uranian moon's past. High heat flows on icy moons like Ariel can also enable viscous flow that removes impact crater topography, a process called viscous relaxation. Here we use numerical modeling to investigate the conditions necessary to viscously relax Ariel's larg
Authors
Michael T. Bland, Chloe B. Beddingfield, Tom A. Nordheim, Donald A. Patthoff, Steven D. Vance
Asteroid impacts and cascading hazards
The initial effects from an asteroid impact are generally well characterized and include thermal radiation and blast waves. If the impactor is sufficiently large, either an earthquake or tsunami can also result, depending on whether the impact occurs over land or water. However, the longer-term effects that extend beyond the area initially affected are less well characterized. Because regional ef
Authors
Timothy N. Titus, D. G. Robertson, Joel B. Sankey, Larry G. Mastin
Ice resource mapping on Mars
This chapter explains the rationale for considering shallowly buried (0 to >5 m depth) water ice in the mid-latitudes of Mars as a resource to support future human missions, and describes a NASA-funded effort to map that ice with existing orbital remote-sensing data. In recent decades, numerous studies have used various datasets to investigate the presence and stability of water ice in the Martian
Authors
Nathaniel E Putzig, Gareth A Morgan, Hanna G Sizemore, David M Hollibaugh Baker, Eric I Petersen, Asmin V Pathare, Colin M. Dundas, Ali M Bramson, Samuel W Courville, Matthew R Perry, Stefano Nerozzi, Zachary M Bain, Rachel H Hoover, Bruce A Campbell, Marco Mastrogiuseppe, Michael T. Mellon, Roberto Seu, Isaac B. Smith
Chemical characterization of San Andreas Fault Observatory at Depth (SAFOD) Phase 3 core
We present new X-ray fluorescence compositions of 27 core samples from Phase 3, Hole G of the San Andreas Fault Observatory at Depth, nearly doubling the published dataset for the core. The new analyses consist of major and trace element compositions and the first published data for rare earth elements from Hole G. Whole-rock compositions were obtained to further the analysis of active geochemical
Authors
Diane E. Moore, Kelly K. Bradbury
Surface fault displacement models for strike-slip faults
Fault displacement models (FDMs) are an essential component of the probabilistic fault displacement hazard analyses (PFDHA), much like ground motion models in the probabilistic seismic hazard analyses for ground motion hazards. In this study, we develop several principal surface FDMs for strike-slip earthquakes. The model development is based on analyses of the new and comprehensive fault displac
Authors
Brian S. J. Chiou, Rui Chen, Kate Thomas, Christopher W. D. Milliner, Timothy E. Dawson, Mark D. Petersen
Strength recovery in quartzite is controlled by changes in friction in experiments at hydrothermal conditions up to 200°C
The rate of fault zone restrengthening between earthquakes can be influenced by both frictional and cohesive healing processes. Friction is dependent on effective normal stress while cohesion is independent of normal stress, potentially explaining—in part—the lack of depth dependence of earthquake stress drops. Although amenable to laboratory testing, few studies have systematically addressed the
Authors
Tamara Nicole Jeppson, David A. Lockner, Nicholas M. Beeler, Stephen H. Hickman
Observations and morphodynamic modeling of decadal-scale morphologic change in estuaries under sea level rise
Sea level rise is expected to affect coastal areas all around the world, including the estuarine environment. New bathymetry collected in 2014 provided a unique opportunity to test the modeling of Elmilady et al. (2019), who presented a morphodynamic DELFT3D model of San Pablo Bay, California, that included detailed tidal water movement, wind-wave action, sediment transport, and resulting bed leve
Authors
Bruce E. Jaffe, Hesham Elmilady, Mick Van der Wegen, Theresa A. Fregoso
User needs assessment for postfire debris-flow inundation hazard products
Debris flows are a type of mass movement that is more likely after wildfires, and while existing hazard assessments evaluate the rainfall intensities that are likely to trigger debris flows, no operational hazard assessment exists for identifying the areas where they will run out after initiation. Fifteen participants who work in a wide range of job functions associated with southern California po
Authors
Katherine R. Barnhart, Veronica Romero, Katherine R. Clifford