Publications
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Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars
During its exploration of the Columbia Hills, the Mars Exploration Rover "Spirit" encountered several similar samples that are distinctly different from Martian meteorites and known Gusev crater soils, rocks, and sediments. Occurring in a variety of contexts and locations, these "Independence class" samples are rough-textured, iron-poor (equivalent FeO ??? 4 wt%), have high Al/Si ratios...
Authors
B. C. Clark, R. E. Arvidson, Ralf Gellert, R.V. Morris, D. W. Ming, L. Richter, S. W. Ruff, J.R. Michalski, W. H. Farrand, A. S. Yen, Kenneth E. Herkenhoff, R. Li, S. W. Squyres, C. Schroder, G. Klingelhofer, J.F. Bell
The occurrence of the colonial ascidian Didemnum sp. on Georges Bank gravel habitat: ecological observations and potential effects on groundfish and scallop fisheries The occurrence of the colonial ascidian Didemnum sp. on Georges Bank gravel habitat: ecological observations and potential effects on groundfish and scallop fisheries
The colonial ascidian Didemnum sp. is present on the Georges Bank fishing grounds in a gravel habitat where the benthic invertebrate fauna has been monitored annually since 1994. The species was not noted before 2002 when large colonies were first observed; and by 2003 and 2004 it covered large areas of the seabed at some locations. The latest survey in 2005 documented the tunicate's...
Authors
P. C. Valentine, J.S. Collie, R.N. Reid, R. G. Asch, Vincent G. Guida, D.S. Blackwood
1400 yr multiproxy record of climate variability from the northern Gulf of Mexico 1400 yr multiproxy record of climate variability from the northern Gulf of Mexico
A continuous decadal-scale resolution record of climate variability over the past 1400 yr in the northern Gulf of Mexico was constructed from a box core recovered in the Pigmy Basin, northern Gulf of Mexico. Proxies include paired analyses of Mg/Ca and δ18O in the white variety of the planktic foraminifer Globigerinoides ruber and relative abundance variations of G. sacculifer in the...
Authors
J.N. Richey, R.Z. Poore, B.P. Flower, T. M. Quinn
Remote sensing of particle backscattering in Chesapeake Bay: a 6-year SeaWiFS retrospective view Remote sensing of particle backscattering in Chesapeake Bay: a 6-year SeaWiFS retrospective view
Traditional field techniques to monitor water quality in large estuaries, such as boat-based surveys and autonomous moored sensors, generally provide limited spatial coverage. Satellite imagery potentially can be used to address both of these limitations. Here, we show that satellite-based observations are useful for inferring total-suspended-solids (TSS) concentrations in estuarine...
Authors
D.G. Zawada, C. Hu, T. Clayton, Z. Chen, J. C. Brock, F. E. Muller-Karger
Athabasca Valles, Mars: A lava-draped channel system Athabasca Valles, Mars: A lava-draped channel system
Athabasca Valles is a young outflow channel system on Mars that may have been carved by catastrophic water floods. However, images acquired by the High-Resolution Imaging Science Experiment camera onboard the Mars Reconnaissance Orbiter spacecraft reveal that Athabasca Valles is now entirely draped by a thin layer of solidified lava - the remnant of a once-swollen river of molten rock...
Authors
Windy L. Jaeger, Laszlo P. Keszthelyi, Alfred S. McEwen, Colin M. Dundas, Paul C. Russell
The colonial ascidian Didemnum sp. A: current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America The colonial ascidian Didemnum sp. A: current distribution, basic biology and potential threat to marine communities of the northeast and west coasts of North America
Didemnum sp. A is a colonial ascidian with rapidly expanding populations on the east and west coasts of North America. The origin of Didemum sp. A is unknown. Populations were first observed on the northeast coast of the U.S. in the late 1980s and on the west coast during the 1990s. It is currently undergoing a massive population explosion and is now a dominant member of many subtidal...
Authors
S.G. Bullard, G. Lambert, M.R. Carman, J. Byrnes, R.B. Whitlatch, G. Ruiz, R. J. Miller, L. Harris, P. C. Valentine, J.S. Collie, J. Pederson, D.C. McNaught, A.N. Cohen, R. G. Asch, J. Dijkstra, K. Heinonen
Regression models for estimating coseismic landslide displacement Regression models for estimating coseismic landslide displacement
Newmark's sliding-block model is widely used to estimate coseismic slope performance. Early efforts to develop simple regression models to estimate Newmark displacement were based on analysis of the small number of strong-motion records then available. The current availability of a much larger set of strong-motion records dictates that these regression equations be updated. Regression...
Authors
R.W. Jibson
Volcanic ash plume identification using polarization lidar: Augustine eruption, Alaska Volcanic ash plume identification using polarization lidar: Augustine eruption, Alaska
During mid January to early February 2006, a series of explosive eruptions occurred at the Augustine volcanic island off the southern coast of Alaska. By early February a plume of volcanic ash was transported northward into the interior of Alaska. Satellite imagery and Puff volcanic ash transport model predictions confirm that the aerosol plume passed over a polarization lidar (0.694 mm...
Authors
Kenneth Sassen, Jiang Zhu, Peter W. Webley, K. Dean, Patrick Cobb
The question of recharge to the deep thermal reservoir underlying the geysers and hot springs of Yellowstone National Park: Chapter H in Integrated geoscience studies in Integrated geoscience studies in the Greater Yellowstone Area—Volcanic, tectonic, The question of recharge to the deep thermal reservoir underlying the geysers and hot springs of Yellowstone National Park: Chapter H in Integrated geoscience studies in Integrated geoscience studies in the Greater Yellowstone Area—Volcanic, tectonic,
The extraordinary number, size, and unspoiled beauty of the geysers and hot springs of Yellowstone National Park (the Park) make them a national treasure. The hydrology of these special features and their relation to cold waters of the Yellowstone area are poorly known. In the absence of deep drill holes, such information is available only indirectly from isotope studies. The δD-δ18O...
Authors
Robert O. Rye, Alfred Hemingway Truesdell
Explosive eruptive record in the Katmai region, Alaska Peninsula: An overview Explosive eruptive record in the Katmai region, Alaska Peninsula: An overview
At least 15 explosive eruptions from the Katmai cluster of volcanoes and another nine from other volcanoes on the Alaska Peninsula are preserved as tephra layers in syn- and post-glacial (Last Glacial Maximum) loess and soil sections in Katmai National Park, AK. About 400 tephra samples from 150 measured sections have been collected between Kaguyak volcano and Mount Martin and from...
Authors
Judy Fierstein
Introduction--Subduction's sharpest arrow Introduction--Subduction's sharpest arrow
No abstract available.
Authors
J.C. Eichelberger
National volcanic ash operations plan for aviation National volcanic ash operations plan for aviation
The National Aviation Weather Program Strategic Plan (1997) and the National Aviation Weather Initiatives (1999) both identified volcanic ash as a high-priority informational need to aviation services. The risk to aviation from airborne volcanic ash is known and includes degraded engine performance (including flameout), loss of visibility, failure of critical navigational and operational
Authors
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