Publications
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The compositions of the lunar crust and upper mantle: Spectral analysis of the inner rings of lunar impact basins
The innermost ring in impact basins exposes material originating from various depths, and can be used to study the composition of the lunar crust with depth. In this study, we conduct quantitative mineralogical analyses of the innermost ring in 13 lunar impact basins using reflectance data from the Kaguya Multiband Imager and radiative transfer modeling. We use results from recent hydrocode modeli
Authors
Myriam Lemelin, Paul G. Lucey, Katarina Miljković, Lisa R. Gaddis, Trent M. Hare, Makiko Ohtake
The formation of gullies on Mars today
A decade of high-resolution monitoring has revealed extensive activity in fresh Martian gullies. Flows within the gullies are diverse: they can be relatively light, neutral or dark, colourful or bland, and range from superficial deposits to 10 m-scale topographic changes. We observed erosion and transport of material within gullies, new terraces, freshly eroded channel segments, migrating sinuous
Authors
Colin M. Dundas, Alfred S. McEwen, Serina Diniega, Candice J. Hansen, Jim N. McElwaince
The flood lavas of Kasei Valles, Mars
Both the northern and southern arms of Kasei Valles are occupied by platy-ridged flood lavas. We have mapped these flows and examined their morphology to better understand their emplacement. The lavas were emplaced as high-flux, turbulent flows (exceeding 106 m3 s−1). Lava in southern Kasei Valles can be traced back up onto the Tharsis rise, which is also the likely source of lavas in the northern
Authors
Colin M. Dundas, Glen E. Cushing, Laszlo P. Kestay
Contaminant baselines and sediment provenance along the Puget Sound Energy Transport Corridor, 2015
The transport of coal and oil can result in contaminated soil, water, and organisms from unintended releases. Trains carrying coal and crude oil regularly pass through Puget Sound, Washington, and an increase in the number of coal and oil trains is expected in the future. This study characterized levels of potentially toxic contaminants in sediment in September 2015: arsenic, metals, and polycycli
Authors
Renee K. Takesue, Pamela L. Campbell
The Shumagin seismic gap structure and associated tsunami hazards, Alaska convergent margin
The potential for a major earthquake in the Shumagin seismic gap, and the tsunami it could generate, was reported in 1971. However, while potentially tsunamigenic splay faults in the adjacent Unimak and Semidi earthquake segments are known, such features along the Shumagin segment were undocumented until recently. To investigate margin structure and search for splay faults, we reprocessed six lega
Authors
Roland E. von Huene, John J. Miller, Anne Krabbenhoeft
Seismic velocity structure across the 2013 Craig, Alaska rupture from aftershock tomography: Implications for seismogenic conditions
The 2013 Craig, Alaska MW 7.5 earthquake ruptured along ∼150 km of the Queen Charlotte Fault (QCF), a right-lateral strike-slip plate boundary fault separating the Pacific and North American plates. Regional shear wave analyses suggest that the Craig earthquake rupturepropagated in the northward direction faster than the S-wave (supershear). Theoretical studies suggest that a bimaterial interface,
Authors
Maureen A. L. Walton, Emily C. Roland, Jacob I. Walter, Sean P. S. Gulick, Peter J. Dotray
The 12 November 2017 Mw 7.3 Ezgeleh–Sarpolzahab (Iran) earthquake and active tectonics of the Lurestan arc
The 12 November 2017 Mw 7.3 Ezgeleh‐Sarpolzahab earthquake is the largest instrumentally recorded earthquake in the Zagros Simply Folded Belt by a factor of ∼10 in seismic moment. Exploiting local, regional, and teleseismic data and synthetic aperture radar interferometry imagery, we characterize the rupture, its aftershock sequence, background seismicity, and regional tectonics. The mainshock rup
Authors
Edwin Nissen, Abdolreza Ghods, Ezgi Karasözen, John R. Elliott, Wiliam D. Barnhart, Eric A. Bergman, Gavin P. Hayes, Mohammadreza Jamal-Reyhani, Majid Nemati, Fengzhou Tan, Wathiq Abdulnaby, Harley M. Benz, Mohammad P. Shahvar, Morteza Talebian, Ling Chen
How physics‐based earthquake simulators might help improve earthquake forecasts
Questions have persisted on the usefulness of physics‐based earthquake simulators with respect to forecasting earthquakes, due mostly to the inevitable assumptions, approximations, and uncertainties. Whether any model is reliable or trustworthy depends entirely on what questions we are asking of it, so the point of this article is to outline a number of currently anticipated and desired inferences
Authors
Edward H. Field
Warming effects of spring rainfall increase methane emissions from thawing permafrost
Methane emissions regulate the near‐term global warming potential of permafrost thaw, particularly where loss of ice‐rich permafrost converts forest and tundra into wetlands. Northern latitudes are expected to get warmer and wetter, and while there is consensus that warming will increase thaw and methane emissions, effects of increased precipitation are uncertain. At a thawing wetland complex in I
Authors
Rebecca B. Neumann, C.J. Moorberg, J.D. Lundquist, J.C. Turner, Mark P. Waldrop, Jack W. McFarland, E.S. Euskirchen, C.W. Edgar, M. R. Turetsky
The NASA Roadmap to Ocean Worlds
In this article, we summarize the work of the NASA Outer Planets Assessment Group (OPAG) Roadmaps to Ocean Worlds (ROW) group. The aim of this group is to assemble the scientific framework that will guide the exploration of ocean worlds, and to identify and prioritize science objectives for ocean worlds over the next several decades. The overarching goal of an Ocean Worlds exploration program as d
Authors
A. Noble Hendrix, T. Hurford, L.M. Barge, Michael T. Bland, J.S. Bowman, W. Brinckerhoff, B. J. Buratti, M. Cable, J. C. Castillo-Rogez, G. C. Collins, S. Diniega, C.R. German, A.G. Hayes, T.M. Hoehler, S. Mehran Hosseini, C. Howett, A.S. McEwen, C. Neish, M. Neveu, T.A. Nordheim, G.W. Patterson, Donald A. Patthoff, C. Phillips, A. Rhoden, B. Schmidt, K. Singer, J. M. Soderblom, S.D. Vance
Communicating hazards—A social science review to meet U.S. Geological Survey needs
This report is for U.S. Geological Survey (USGS)—and any other—hazard scientists who want to improve the understanding and use of their scientific information, particularly by non-experts. In order for people to use science, they need to understand it. The highly technical, specialized nature of scientific information makes that difficult, particularly when few scientists are trained to communicat
Authors
Kerry F. Milch, Suzanne C. Perry, Jennifer L. Bruce
Temperature model in support of the U.S. Geological Survey National Crustal Model for seismic hazard Ssudies
The U.S. Geological Survey National Crustal Model (NCM) is being developed to assist with earthquake hazard and risk assessment by supporting estimates of ground shaking in response to an earthquake. The period-dependent intensity and duration of shaking depend upon the three-dimensional seismic velocity, seismic attenuation, and density distribution of a region, which in turn is governed to a lar
Authors
Oliver S. Boyd