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Publications

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Thermal measurements of dark and bright surface features on Vesta as derived from Dawn/VIR

Remote sensing data acquired during Dawn’s orbital mission at Vesta showed several local concentrations of high-albedo (bright) and low-albedo (dark) material units, in addition to spectrally distinct meteorite impact ejecta. The thermal behavior of such areas seen at local scale (1-10 km) is related to physical properties that can provide information about the origin of those materials. We use Da
Authors
Federico Tosi, Maria Teresa Capria, M.C. De Sanctis, J.-Ph. Combe, F. Zambon, A. Nathues, S. E. Schröder, J.-Y. Li, E. Palomba, A. Longobardo, D.T. Blewett, B.W. Denevi, E. Palmer, F. Capaccioni, E. Ammannito, Timothy N. Titus, D.W. Mittlefehldt, J.M. Sunshine, C.T. Russell, C.A. Raymond, Dawn/VIR Team

Elders recall an earlier tsunami on Indian Ocean shores

Ten years on, the Indian Ocean tsunami of 26 December 2004 still looms large in efforts to reduce coastal risk. The disaster has spurred worldwide advances in tsunami detection and warning, tsunami-risk assessment, and tsunami awareness [Satake, 2014]. Nearly a lifetime has passed since the northwestern Indian Ocean last produced a devastating tsunami. Documentation of this tsunami, in November 1
Authors
Din Mohammad Kakar, Ghazala Naeem, Abdullah Usman, Haider Hasan, Hira Lohdi, Seshachalam Srinivasalu, Vanessa Andrade, C.P. Rajendran, Abdolmajid Naderi Beni, Mohammad Ali Hamzeh, Goesta Hoffmann, Noora Al Balushi, Nora Gale, Ardito Kodijat, Hermann M. Fritz, Brian F. Atwater

Late quaternary paleoseismology of the west valley fault zone: Insights from the Baileys Lake trench site

No abstract available.
Authors
Michael D. Hylland, Christopher B. DuRoss, Greg N. McDonald, Susan S. Olig, Charles G. Oviatt, Shannon Mahan, Anthony J. Crone, Stephen F. Personius

Geologic and physiographic controls on bed-material yield, transport, and channel morphology for alluvial and bedrock rivers, western Oregon

The rivers of western Oregon have diverse forms and characteristics, with channel substrates ranging from continuous alluvial gravel to bare bedrock. Analysis of several measurable morphologic attributes of 24 valley reaches on 17 rivers provides a basis for comparing nonalluvial and alluvial channels. Key differences are that alluvial reaches have greater bar area, greater migration rates, and sh
Authors
James E. O'Connor, Joseph F. Mangano, Scott A. Anderson, J. Rose Wallick, Krista L. Jones, Mackenzie K. Keith

Continuous monitoring of Hawaiian volcanoes with thermal cameras

Continuously operating thermal cameras are becoming more common around the world for volcano monitoring, and offer distinct advantages over conventional visual webcams for observing volcanic activity. Thermal cameras can sometimes “see” through volcanic fume that obscures views to visual webcams and the naked eye, and often provide a much clearer view of the extent of high temperature areas and ac
Authors
Matthew R. Patrick, Tim R. Orr, Loren Antolik, Robert Lopaka Lee, Kevan P. Kamibayashi

Geodetic constraints on the 2014 M 6.0 South Napa earthquake

On 24 August 2014, the M 6.0 South Napa earthquake shook much of the San Francisco Bay area, leading to significant damage in the Napa Valley. The earthquake occurred in the vicinity of the West Napa fault (122.313° W, 38.22° N, 11.3 km), a mapped structure located between the Rodger’s Creek and Green Valley faults, with nearly pure right‐lateral strike‐slip motion (strike 157°, dip 77°, rake –169
Authors
William D. Barnhart, Jessica R. Murray, S H Yun, Jerry L. Svarc, SV Samsonov, EJ Fielding, Benjamin A. Brooks, Pietro Milillo

High-resolution digital elevation model of Mount St. Helens crater and upper North Fork Toutle River basin, Washington, based on an airborne lidar survey of September 2009

The lateral blast, debris avalanche, and lahars of the May 18th, 1980, eruption of Mount St. Helens, Washington, dramatically altered the surrounding landscape. Lava domes were extruded during the subsequent eruptive periods of 1980–1986 and 2004–2008. More than three decades after the emplacement of the 1980 debris avalanche, high sediment production persists in the North Fork Toutle River basin,
Authors
Adam R. Mosbrucker

Seismicity of the Earth 1900-2013 East African Rift

The East African Rift system (EARS) is a 3,000-km-long Cenozoic age continental rift extending from the Afar triple junction, between the horn of Africa and the Middle East, to western Mozambique. Sectors of active extension occur from the Indian Ocean, west to Botswana and the Democratic Republic of the Congo (DRC). It is the only rift system in the world that is active on a continent-wide scale,
Authors
Gavin P. Hayes, Eric S. Jones, Timothy J. Stadler, William D. Barnhart, Daniel E. McNamara, Harley M. Benz, Kevin P. Furlong, Antonio Villaseñor

Science during crisis: the application of social science during major environmental crises

Historical and contemporary experience suggests that science plays an increasingly critical role in governmental and institutional responses to major environmental crises. Recent examples include major western wildfires (2009), the Deepwater Horizon oil spill (2010), the Fukushima nuclear accident (2011), and Hurricane Sandy (2012). The application of science during such crises has several distin
Authors
Gary Machlis, Kris Ludwig

Chemistry and texture of the rocks at Rocknest, Gale Crater: Evidence for sedimentary origin and diagenetic alteration

A suite of eight rocks analyzed by the Curiosity Rover while it was stopped at the Rocknest sand ripple shows the greatest chemical divergence of any potentially sedimentary rocks analyzed in the early part of the mission. Relative to average Martian soil and to the stratigraphically lower units encountered as part of the Yellowknife Bay formation, these rocks are significantly depleted in MgO, wi
Authors
Diana L. Blaney, R. C. Wiens, S. Maurice, S.M. Clegg, Ryan Anderson, L.C. Kah, S. Le Mouélic, A. Ollila, N. Bridges, R. Tokar, G. Berger, J.C. Bridges, A. Cousin, B. Clark, M.D. Dyar, P.L. King, N. Lanza, N. Mangold, P.-Y. Meslin, H. Newsom, S. Schroder, S. Rowland, J. Johnson, L. Edgar, O. Gasnault, O. Forni, M. Schmidt, W. Goetz, K. Stack, D. Sumner, M. Fisk, M.B. Madsen

Component geochronology in the polyphase ca. 3920 Ma Acasta Gneiss

The oldest compiled U–Pb zircon ages for the Acasta Gneiss Complex in the Northwest Territories of Canada span about 4050–3850 Ma; yet older ca. 4200 Ma xenocrystic U–Pb zircon ages have also been reported for this terrane. The AGC expresses at least 25 km2 of outcrop exposure, but only a small subset of this has been documented in the detail required to investigate a complex history and resolve d
Authors
Stephen J. Mojzsis, Nicole L. Cates, Guillaume Caro, Dustin Trail, Oleg Abramov, Martin Guitreau, Janne Blichert-Toft, Michelle D. Hopkins, Wouter Bleeker

A depth-averaged debris-flow model that includes the effects of evolving dilatancy: II. Numerical predictions and experimental tests.

We evaluate a new depth-averaged mathematical model that is designed to simulate all stages of debris-flow motion, from initiation to deposition. A companion paper shows how the model’s five governing equations describe simultaneous evolution of flow thickness, solid volume fraction, basal pore-fluid pressure, and two components of flow momentum. Each equation contains a source term that represent
Authors
David L. George, Richard M. Iverson
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