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Page 2136, results 53376 - 53400

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Surface processes recorded by rocks and soils on Meridiani Planum, Mars: Microscopic Imager observations during Opportunity's first three extended missions
Kenneth E. Herkenhoff, John P. Grotzinger, Andrew H. Knoll, Scott M. McLennan, Catherine M. Weitz, Aileen Yingst, Robert Anderson, Brent A. Archinal, Raymond E. Arvidson, Janet M. Barrett, Kris J. Becker, James F. Bell, Charles Budney, Mary G. Chapman, Debbie Cook, Bethany L. Ehlmann, Brenda Franklin, Lisa R. Gaddis, Donna M. Galuszka, Patricia A. Garcia, Paul E. Geissler, Trent M. Hare, Elpitha Howington-Kraus, Jeffrey R. Johnson, Laszlo P. Keszthelyi, Randolph L. Kirk, Peter Lanagan, Ella M. Lee, Craig Leff, Justin N. Maki, Kevin F. Mullins, Timothy J. Parker, Bonnie L. Redding, Mark R. Rosiek, Michael H. Sims, Laurence A. Soderblom, Nicole Spanovich, Richard Springer, Steven W. Squyres, Daniel A. Stolper, Robert M. Sucharski, Tracie L. Sucharski, Robert Sullivan, James M. Torson
2008, Journal of Geophysical Research E: Planets (113) 1-39
The Microscopic Imager (MI) on the Mars Exploration Rover Opportunity has returned images of Mars with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies of the rocks and soils at the Meridiani Planum landing site. Designed to simulate a geologist's hand lens, the MI is...
Effects of landscape gradients on wetland vegetation communities: information for large-scale restoration
Christa L. Zweig, Wiley M. Kitchens
2008, Wetlands (28) 1086-1096
Projects of the scope of the restoration of the Florida Everglades require substantial information regarding ecological mechanisms, and these are often poorly understood. We provide critical base knowledge for Everglades restoration by characterizing the existing vegetation communities of an Everglades remnant, describing how present and historic hydrology affect wetland vegetation...
In-situ observations of the physical properties of the Martian surface
Kenneth E. Herkenhoff, M. P. Golombek, E.A. Guinness, J.B. Johnson, A. Kusack, L. Richter, R.J. Sullivan, S. Gorevan
Jim Bell, editor(s)
2008, Book chapter, The martian surface: Composition, mineralogy, and physical properties
The physical properties of rocks and soils on the surface of Mars have been investigated by several landed spacecraft. Studies of these physical properties constrain interpretation of Martian geologic processes and provide engineering data for future mission planning. As on Earth, these properties vary considerably from place to place, and...
Geometric performance comparison between the OLI and the ETM+
James C. Storey, Mike Choate, Kenton Lee
2008, Conference Paper
The Landsat Data Continuity Mission (LDCM) Operational Land Imager (OLI) is the successor to the Landsat 7 Enhanced Thematic Mapper Plus (ETM+) instrument and features a pushbroom architecture that is more geometrically stable than the whiskbroom scanner of the ETM+. As a tradeoff of this architecture selection, imagery must be...
Forewarned is forearmed! Progress in development of the U.S. National Early Detection and Rapid Response System for invasive plants: Proposal for a North American early warning system for invasive plants
Randy G. Westbrooks
2008, Conference Paper, Proceedings of 2008 Weeds Against Borders
Currently, a National Early Detection and Rapid Response System (EDRR) for Invasive Plants is being developed in the United States. Conceptually, the system is a coordinated framework of local, state, and national interagency groups that is designed to prevent the establishment and spread of new invasive plants through early detection...
First in situ investigation of a dark wind streak on Mars
Paul E. Geissler, J. R. Johnson, R. Sullivan, Kenneth E. Herkenhoff, D. W. Mittlefehldt, Robin L. Fergason, D. Ming, R. Morris, S. Squyres, Laurence A. Soderblom, M. Golombek
2008, Journal of Geophysical Research E: Planets (113)
Prominent low‐albedo wind streaks issue from embayments at the north end of Victoria crater in Meridiani Planum, the site of surface investigations by the Mars Exploration Rover Opportunity. Opportunity was sent to examine the darkest of these wind streaks and compare it to the adjacent soil in the brighter corridor...
High-resolution seismic images and seismic velocities of the San Andreas fault zone at Burro Flats, Southern California
C. C. Tsai, Rufus D. Catchings, Mark R. Goldman, Michael J. Rymer, P. Schnurle, H. W. Chen
2008, Bulletin of the Seismological Society of America (98) 2948-2961
To better understand the structure of the San Andreas fault (SAF) at Burro Flats in southern California, we acquired a three-dimensional combined set of seismic reflection and refraction profiles centered on the main active trace at Burro Flats. In this article, we discuss the variation in shallow-depth velocities along each...
Spirit Mars Rover Mission to the Columbia Hills, Gusev Crater: Mission overview and selected results from the Cumberland Ridge to Home Plate
R. E. Arvidson, S. W. Ruff, R.V. Morris, D. W. Ming, L.S. Crumpler, A. S. Yen, S. W. Squyres, R.J. Sullivan, J.F. Bell III, N.A. Cabrol, B. C. Clark, W. H. Farrand, R. Gellert, R. Greenberger, J. A. Grant, E.A. Guinness, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, G. Klingelhoefer, K. W. Lewis, R. Li, T.J. McCoy, J. Moersch, H.Y. McSween, S.L. Murchie, M. Schmidt, C. Schroeder, A. Wang, S. Wiseman, M.B. Madsen, W. Goetz, S. M. McLennan
2008, Journal of Geophysical Research E: Planets (113)
This paper summarizes the Spirit rover operations in the Columbia Hills of Gusev Crater from sols 513 to 1476 and provides an overview of selected findings that focus on synergistic use of the Athena Payload and comparisons to orbital data. Results include discovery of outcrops (Voltaire) on Husband Hill that...
Stratigraphic models for deep-water sedimentary systems
Michael H. Gardner, James M. Borer, Brian W. Romans, Noelia Baptista, Erik K. Kling, Diah Hanggoro, Jesse J. Melick, Roger M. Wagerle, Marieke Dechesne, Mary M. Carr, Robert Amerman, Safian Atan
2008, Book chapter, Answering the challenges of production from deep-water reservoirs: Analogues and case histories to aid a new generatio
Stratigraphic models predict sedimentary architecture. Prediction requires understanding systems across a sufficient range of scales. To be predictive a model must address the interaction of multiple process-response relationships. For deep-water systems these processes include (1) subaqueous flow initiation and transformation, (2) linkages between channel, levee and lobe processes, and (3)...
A landslide in Tertiary marine shale with superheated fumaroles, Coast Ranges, California
Robert H. Mariner, Scott A. Minor, A. King, J.R. Boles, Karl S. Kellogg, William C. Evans, Gary Landis, A.G. Hunt, Christy B. Till
2008, Geology (36) 959-962
In August 2004, a National Forest fire crew extinguished a 1.2 ha fire in a wilderness area ~40 km northeast of Santa Barbara, California. Examination revealed that the fire originated on a landslide dotted with superheated fumaroles. A 4 m borehole punched near the hottest (262 °C) fumarole had a...
Book review: The ecology and behavior of amphibians
Susan C. Walls
2008, The Quarterly Review of Biology (83)
This state‐of‐the‐art book has made its timely emergence amid a crisis of global magnitude: that of population declines, range reductions, and extinctions of numerous species of amphibians. A clear understanding of the fundamental concepts in amphibian biology is crucial to the success of any conservation effort. This volume compiles the...
Diversity increases biomass production for trematode parasites in snails
Ryan F. Hechinger, Kevin D. Lafferty, Armand M. Kuris
2008, Proceedings of the Royal Society B: Biological Sciences (275) 2707-2714
Increasing species diversity typically increases biomass in experimental assemblages. But there is uncertainty concerning the mechanisms of diversity effects and whether experimental findings are relevant to ecological process in nature. Hosts for parasites provide natural, discrete replicates of parasite assemblages. We considered how diversity affects standing-stock biomass for a highly...
Ecosystem consequences of fish parasites
Kevin D. Lafferty
2008, Journal of Fish Biology (73) 2083-2093
In most aquatic ecosystems, fishes are hosts to parasites and, sometimes, these parasites can affect fish biology. Some of the most dramatic cases occur when fishes are intermediate hosts for larval parasites. For example, fishes in southern California estuaries are host to many parasites. The most common of these parasites,...
Coast salish and U.S. Geological Survey: Tribal journey water quality project
Sarah K. Akin, Eric E. Grossman, Debra Lekanof, Charles J. O’Hara
2008, Report
The ancestral waters of the Coast Salish People, the Salish Sea, comprise a large inland sea contained within both United States (Puget Sound) and Canadian (Georgia Strait) territory. The Salish Sea is home to more than 220 species of fish, 29 species of marine mammals, more than 40 species of...
Breeding phenology and reproductive success of the Brandt's Cormorant at three nearshore colonies in central California, 1997-2001
Nathan M. Jones, Gerard McChesney, Michael W. Parker, Julie L. Yee, Harry R. Carter, Richard T. Golightly
2008, Waterbirds (31) 505-519
Brandt's Cormorant (Phalacrocorax penicillatus) breeding effort, phenology and success were studied in 1997-2001 at three colonies spanning approximately 200 km of the central California coast: Point Reyes (PR); Devil's Slide Rock and Mainland (DS); and Castle-Hurricane Colony Complex (CH). Breeding effort was reduced at all three colonies in the 1998...
Comparison of effects of humans versus wildlife-detector dogs
Jill S. Heaton, Mary E. Cablk, Kenneth E. Nussear, Todd C. Esque, Philip A. Medica, John C. Sagebiel, S. Steve Francis
2008, Southwestern Naturalist (53) 472-479
The use of dogs (Canis lupus familiaris) trained to locate wildlife under natural conditions may increase the risk of attracting potential predators or alter behavior of target species. These potentially negative effects become even more problematic when dealing with threatened or endangered species, such as the Mojave Desert tortoise (Gopherus...
Survival and migration behavior of juvenile salmonids at McNary Dam, 2006
2008, Report
During 2006, we used acoustic telemetry and a route-specific survival model (RSSM, Skalski et al. 2002) to estimate behavior, passage, and survival of juvenile salmonids during two different spill operations and diel periods at McNary Dam. An evaluation of 12-h versus 24-h spill was proposed for the spring migration period...
Changes in fish diets and food web mercury bioaccumulation induced by an invasive planktivorous fish
Collin A. Eagles-Smith, Thomas H. Suchanek, Arthur E. Colwell, Norman L. Anderson, Peter B. Moyle
2008, Ecological Applications (18) A213-A226
The invasion, boom, collapse, and reestablishment of a population of the planktivorous threadfin shad in Clear Lake, California, USA, were documented over a 20-year period, as were the effects of changing shad populations on diet and mercury (Hg) bioaccumulation in nearshore fishes. Threadfin shad competitively displaced other planktivorous fish in...
Rapid response of a hydrologic system to volcanic activity: Masaya volcano, Nicaragua
S.C.P. Pearson, C.B. Connor, W. E. Sanford
2008, Geology (36) 951-954
Hydrologic systems change in response to volcanic activity, and in turn may be sensitive indicators of volcanic activity. Here we investigate the coupled nature of magmatic and hydrologic systems using continuous multichannel time series of soil temperature collected on the flanks of Masaya volcano, Nicaragua, one of the most active...
The Importance of Uncertainty and Sensitivity Analysis in Process-based Models of Carbon and Nitrogen Cycling in Terrestrial Ecosystems with Particular Emphasis on Forest Ecosystems — Selected Papers from a Workshop Organized by the International Society for Ecological Modelling (ISEM) at the Third Biennal Meeting of the International Environmental Modelling and Software Society (IEMSS) in Burlington, Vermont, USA, August 9-13, 2006
Guy R. Larocque, Jagtar S. Bhatti, Jinxun Liu, James C. Ascough II, Andrew M. Gordon
2008, Ecological Modelling (219) 261-263
Many process-based models of carbon (C) and nitrogen (N) cycles have been developed for terrestrial ecosystems, including forest ecosystems. They address many basic issues of ecosystems structure and functioning, such as the role of internal feedback in ecosystem dynamics. The critical factor in these phenomena is scale, as these processes...
Towards continuous 4D microgravity monitoring of volcanoes
Glyn Williams-Jones, Hazel Rymer, Guillaume Mauri, Joachim Gottsmann, Michael P. Poland, Daniele Carbone
2008, Geophysics (73) WA19-WA28
Four-dimensional or time-lapse microgravity monitoring has been used effectively on volcanoes for decades to characterize the changes in subsurface volcanic systems. With measurements typically lasting from a few days to weeks and then repeated a year later, the spatial resolution of theses studies is often at the expense of temporal...
Comparison of the modified Biot-Gassmann theory and the Kuster-Toksöz theory in predicting elastic velocities of sediments
Myung W. Lee
2008, Scientific Investigations Report 2008-5196
Elastic velocities of water-saturated sandstones depend primarily on porosity, effective pressure, and the degree of consolidation. If the dry-frame moduli are known, from either measurements or theoretical calculations, the effect of pore water on velocities can be modeled using the Gassmann theory. Kuster and Toksoz developed a theory based on...
Analysis of the Magnitude and Frequency of Peak Discharge and Maximum Observed Peak Discharge in New Mexico and Surrounding Areas
Scott D. Waltemeyer
2008, Scientific Investigations Report 2008-5119
Estimates of the magnitude and frequency of peak discharges are necessary for the reliable design of bridges, culverts, and open-channel hydraulic analysis, and for flood-hazard mapping in New Mexico and surrounding areas. The U.S. Geological Survey, in cooperation with the New Mexico Department of Transportation, updated estimates of peak-discharge magnitude...
Jurassic-Cretaceous Composite Total Petroleum System and Geologic Assessment of Oil and Gas Resources of the North Cuba Basin, Cuba
U.S. Geological Survey North Cuba Basin Assessment Team
2008, Data Series 69-M
The purpose of the U.S. Geological Survey's (USGS) World Oil and Gas Assessment is to develop geologically based hypotheses regarding the potential for additions to oil and gas reserves in priority areas of the world. The U.S. Geological Survey (USGS) completed an assessment of the undiscovered oil and gas potential...