Publications
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Better approaches to managing drought in the American Southwest
The second in a series of USGS Southwest Region (SWR) “Science Exchange” annual workshops, focused on USGS drought science. The participants considered how extreme drought conditions are evolving in much of the American southwest, with an emphasis on integrated drought science planning at the USGS bureau and program levels. The increased need for interdisciplinary science to support resource-manag
Authors
Patrick Lambert, Timothy N. Titus, Andrea Ostroff
Dark halos produced by current impact cratering on Mars
Hundreds of new impact craters have been observed to form on Mars since spacecraft began imaging that planet. New impact craters produced visible ejecta deposits and many of them also have visible rays, similar to lunar and mercurian craters. However, some of the new martian impact craters have a circular feature of relatively low reflectance that we call a “halo.” This feature is distinct from th
Authors
Gwendolyn D. Bart, Ingrid J. Daubar, Boris A Ivanov, Colin M. Dundas, Alfred S. McEwen
Evidence for plunging river plume deposits in the Pahrump Hills member of the Murray formation, Gale crater, Mars
Recent robotic missions to Mars have offered new insights into the extent, diversity and habitability of the Martian sedimentary rock record. Since the Curiosity rover landed in Gale crater in August 2012, the Mars Science Laboratory Science Team has explored the origins and habitability of ancient fluvial, deltaic, lacustrine and aeolian deposits preserved within the crater. This study describes
Authors
Kathryn M. Stack, John P. Grotzinger, Michael P. Lamb, Sanjeev Gupta, David M. Rubin, Linda C. Kah, Lauren A. Edgar, Deirdra M. Fey, Joel A. Hurowitz, Marie J. McBride, Frances Rivera-Hernández, Dawn Y. Sumner, Jason K. Van Beek, Rebecca M. E. Williams, R. Aileen Yingst
Planetary geologic mapping—Program status and future needs
The United States Geological Survey’s (USGS) Planetary Geologic Map Coordination Group (Flagstaff, Ariz.) surveyed planetary geoscience map makers and users to determine the importance, relevance, and usability of such products to their planetary science research and to current and future needs of the planetary science community. This survey was prepared because the planetary science community lac
Authors
James A. Skinner, Alexandra E. Huff, Corey M. Fortezzo, Tenielle Gaither, Trent M. Hare, Marc A. Hunter, Holly Buban
Clastic pipes and mud volcanism across Mars: Terrestrial analog evidence of past Martian groundwater and subsurface fluid mobilization
Clastic pipes are cylindrical injection features that vertically crosscut bedding with sharp contacts. Terrestrial pipes have cylindrical morphologies, massive or radially graded interiors, and raised outer rims. Increased grain size and subsequent cementation along the more porous edges makes the rims more resistant to weathering. Pipes have crosscutting relationships with other pipes due to mult
Authors
D. F. Wheatley, M. A. Chan, Chris Okubo
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
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
Revisiting the Apollo photogrammetric mapping system
The integrated photogrammetric mapping system flown on the last three Apollo lunar missions (15, 16, and 17) in 1971 and 1972 incorporated a Metric (mapping) Camera, a high-resolution Panoramic Camera, and a star camera and laser altimeter to provide support data. The U.S. Geological Survey’s Astrogeology Science Center, the Intelligent Robotics Group of the NASA Ames Research Center, and Arizona
Authors
Kenneth Edmundson, Oleg Alexandrov, Brent Archinal, Kris J. Becker, Tammy L Becker, Jesse Mapel, Zachary M. Moratto, Ara V. Nefian, Janet Richie, Mark S. Robinson, Makayla Shepherd, John Shinaman, Ethan Smith
Impact cratering of Mercury
No abstract available.
Authors
Clark R. Chapman, David M. H. Baker, Olivier S. Barnouin, Caleb I. Fassett, Simone Marchi, William Merline, Lillian R. Ostrach, Louise Prockter, Robert G. Strom
The volcanic character of Mercury
No abstract available.
Authors
Paul K Byrne, Jennifer L Whitten, Christian Klimczak, Francis M. McCubbin, Lillian R. Ostrach