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Page 1009, results 25201 - 25225

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Not all publications have extents, not all extents are completely accurate
Environmental and geochemical record of human-induced changes in C storage during the last millennium in a temperate wetland (Las Tablas de Daimiel National Park, central Spain)
F. Dominguez-Castro, J.I. Santisteban, R. Mediavilla, W.E. Dean, E. Lopez-Pamo, M. J. Gil-Garcia, M. B. Ruiz-Zapata
2006, Conference Paper, Tellus, Series B: Chemical and Physical Meteorology
Las Tablas de Daimiel National Park has experienced many hydrological and ecological modifications through out its history, both of natural as well as anthropogenic origin, which have affected its carbon storage capacity and carbon fluxes. The study of those variations has been carried out by the analysis of its sedimentary...
Atmospheric chemistry of a 33-34 hour old volcanic cloud from Hekla Volcano (Iceland): Insights from direct sampling and the application of chemical box modeling
William I. Rose Jr., G.A. Millard, T.A. Mather, D.E. Hunton, B. Anderson, C. Oppenheimer, B.F. Thornton, T.M. Gerlach, A.A. Viggiano, Y. Kondo, T.M. Miller, J.O. Ballenthin
2006, Journal of Geophysical Research D: Atmospheres (111)
On 28 February 2000, a volcanic cloud from Hekla volcano, Iceland, was serendipitously sampled by a DC-8 research aircraft during the SAGE III Ozone Loss and Validation Experiment (SOLVE I). It was encountered at night at 10.4 km above sea level (in the lower stratosphere) and 33-34 hours after emission....
Effect of thermal maturation on the K-Ar, Rb-Sr and REE systematics of an organic-rich New Albany Shale as determined by hydrous pyrolysis
Norbert Clauer, Sambhudas Chaudhuri, M. D. Lewan, T. Toulkeridis
2006, Chemical Geology (234) 169-177
Hydrous-pyrolysis experiments were conducted on an organic-rich Devonian-Mississippian shale, which was also leached by dilute HCl before and after pyrolysis, to identify and quantify the induced chemical and isotopic changes in the rock. The experiments significantly affect the organic-mineral organization, which plays an important role in natural interactions during diagenetic...
Soluble reactive phosphorus transport and retention in tropical, rainforest streams draining a volcanic and geothermally active landscape in Costa Rica.: Long-term concentration patterns, pore water environment and response to ENSO events
F.J. Triska, C. M. Pringle, J.H. Duff, R.J. Avanzino, A. Ramirez, M. Ardon, A. P. Jackman
2006, Biogeochemistry (81) 131-143
Soluble reactive phosphorus (SRP) transport/retention was determined at four sites in three rainforest streams draining La Selva Biological Station, Costa Rica. La Selva is located at the base of the last remaining intact rainforest transect from 30 m above sea level to 3000 m along the entire Caribbean slope of...
A simple method of predicting S-wave velocity
Myung W. Lee
2006, Geophysics (71)
Prediction of shear-wave velocity plays an important role in seismic modeling, amplitude analysis with offset, and other exploration applications. This paper presents a method for predicting S-wave velocity from the P-wave velocity on the basis of the moduli of dry rock. Elastic velocities of water-saturated sediments at low frequencies can...
Coseismic and initial postseismic deformation from the 2004 Parkfield, California, earthquake, observed by global positioning system, electronic distance meter, creepmeters, and borehole strainmeters
J. Langbein, J.R. Murray, Hollice A. Snyder
2006, Bulletin of the Seismological Society of America (96)
Global Positioning System (GPS), electronic distance meter, creepmeter, and strainmeter measurements spanning the M 6.0 Parkfield, California, earthquake are examined. Using these data from 100 sec through 9 months following the main-shock, the Omori's law, with rate inversely related to time, l/t p and p ranging between 0.7 and 1.3,...
Shear velocity estimates on the inner shelf off Grays Harbor, Washington, USA
C. R. Sherwood, J.R. Lacy, G. Voulgaris
2006, Continental Shelf Research (26) 1995-2018
Shear velocity was estimated from current measurements near the bottom off Grays Harbor, Washington between May 4 and June 6, 2001 under mostly wave-dominated conditions. A downward-looking pulse-coherent acoustic Doppler profiler (PCADP) and two acoustic-Doppler velocimeters (field version; ADVFs) were deployed on a tripod at 9-m water depth. Measurements from...
Comet 81P/wild 2 under a microscope
D. Brownlee, P. Tsou, J. Aleon, Alexander C. M. O’D C. M., T. Araki, S. Bajt, G.A. Baratta, R. Bastien, P. Bland, P. Bleuet, J. Borg, J.P. Bradley, A. Brearley, F. Brenker, S. Brennan, J.C. Bridges, N.D. Browning, J.R. Brucato, E. Bullock, M.J. Burchell, H. Busemann, Anna L. Butterworth, M. Chaussidon, A. Cheuvront, M. Chi, M.J. Cintala, B. C. Clark, S.J. Clemett, G. Cody, L. Colangeli, G. Cooper, P. Cordier, C. Daghlian, Z. Dai, L. D’Hendecourt, Z. Djouadi, G. Dominguez, T. Duxbury, J.P. Dworkin, D.S. Ebel, T.E. Economou, S. Fakra, S.A.J. Fairey, S. Fallon, G. Ferrini, T. Ferroir, H. Fleckenstein, C. Floss, G. Flynn, I.A. Franchi, M. Fries, Z. Gainsforth, J.-P. Gallien, M. Genge, M.K. Gilles, P. Gillet, J. Gilmour, D.P. Glavin, M. Gounelle, Monica M. Grady, G.A. Graham, P.G. Grant, S.F. Green, F. Grossemy, L. Grossman, J. N. Grossman, Y. Guan, K. Hagiya, R. Harvey, P. Heck, G.F. Herzog, P. Hoppe, F. Horz, J. Huth, I.D. Hutcheon, K. Ignatyev, H. Ishii, M. Ito, D. Jacob, C. Jacobsen, S. Jacobsen, S. Jones, D. Joswiak, A. Jurewicz, A.T. Kearsley, L.P. Keller, H. Khodja, A.L.D. Kilcoyne, J. Kissel, A. Krot, F. Langenhorst, A. Lanzirotti, L. Le, L.A. Leshin, J. Leitner, L. Lemelle, H. Leroux, M.-C. Liu, K. Luening, I. Lyon, G. MacPherson, M.A. Marcus, K. Marhas, B. Marty, G. Matrajt, K. McKeegan, A. Meibom, V. Mennella, K. Messenger, S. Messenger, T. Mikouchi, S. Mostefaoui, T. Nakamura, T. Nakano, M. Newville, L.R. Nittler, I. Ohnishi, K. Ohsumi, K. Okudaira, D.A. Papanastassiou, R. Palma, M.E. Palumbo, R. O. Pepin, D. Perkins, M. Perronnet, P. Pianetta, W. Rao, F.J.M. Rietmeijer, F. Robert, D. Rost, A. Rotundi, R. Ryan, S.A. Sandford, C.S. Schwandt, T.H. See, D. Schlutter, J. Sheffield-Parker, A. Simionovici, S. Simon, I. Sitnitsky, C.J. Snead, M. K. Spencer, F.J. Stadermann, A. Steele, T. Stephan
2006, Science (314) 1711-1716
The Stardust spacecraft collected thousands of particles from comet 81P/Wild 2 and returned them to Earth for laboratory study. The preliminary examination of these samples shows that the nonvolatile portion of the comet is an unequilibrated assortment of materials that have both presolar and solar system origin. The comet contains...
Incorporating diverse data and realistic complexity into demographic estimation procedures for sea otters
M. Timothy Tinker, Daniel F. Doak, James A. Estes, Brian B. Hatfield, Michelle M. Staedler, Arthur Gross
2006, Ecological Applications (16) 2293-2312
Reliable information on historical and current population dynamics is central to understanding patterns of growth and decline in animal populations. We developed a maximum likelihood-based analysis to estimate spatial and temporal trends in age/sex-specific survival rates for the threatened southern sea otter (Enhydra lutris nereis), using annual population censuses and...
Coseismic and postseismic slip of the 2004 Parkfield earthquake from space-geodetic data
I.A. Johanson, E.J. Fielding, F. Rolandone, R. Burgmann
2006, Bulletin of the Seismological Society of America (96)
We invert interferometric synthetic aperture radar (InSAR) data jointly with campaign and continuous global positioning system (GPS) data for slip in the coseismic and postseismic periods of the 2004 Parkfield earthquake. The InSAR dataset consists of eight interferograms from data collected by the Envisat and Radarsat satellites spanning the time...
Nitrogen sources and cycling in the San Francisco Bay estuary: A nitrate dual isotopic composition approach
Scott D. Wankel, C. Kendall, C.A. Francis, A. Paytan
2006, Limnology and Oceanography (51) 1654-1664
We used the dual isotopic composition of nitrate (δ15N and δ18O) within the estuarine system of San Francisco (SF) Bay, California, to explore the utility of this approach for tracing sources and cycling of nitrate (NO2−). Surface water samples from 49 sites within the estuary were sampled during July–August 2004....
Evaluation of aerial survey methods for Dall's sheep
Mark S. Udevitz, Brad S. Shults, Layne G. Adams, Christopher Kleckner
2006, Wildlife Society Bulletin (34) 732-740
Most Dall's sheep (Ovis dalli dalli) population-monitoring efforts use intensive aerial surveys with no attempt to estimate variance or adjust for potential sightability bias. We used radiocollared sheep to assess factors that could affect sightability of Dall's sheep in standard fixed-wing and helicopter surveys and to evaluate feasibility of methods...
Exhumation of Greater Himalayan rock along the main central thrust in Nepal: Implications for channel flow
D.M. Robinson, O.N. Pearson
Law R.D.Searle M.P.Godin L., editor(s)
2006, Conference Paper, Geological Society Special Publication
South-vergent channel flow from beneath the Tibetan Plateau may have played an important role in forming the Himalaya. The possibility that Greater Himalayan rocks currently exposed in the Himalayan Fold-Thrust Belt flowed at mid-crustal depths before being exhumed is intriguing, and may suggest a natural link between orogenic processes operating...
Crustal structure and tectonics of the northern part of the Southern Granulite Terrane, India
V.V. Rao, K. Sain, P.R. Reddy, Walter D. Mooney
2006, Earth and Planetary Science Letters (251) 90-103
Deep seismic reflection studies investigating the exposed Archean lower continental crust of the Southern Granulite Terrane, India, yield important constraints on the nature and evolution of the deep crust, including the formation and exhumation of granulites. Seismic reflection images along the Kuppam–Bhavani profile...
Geodetic antenna calibration test in the Antarctic environment
A. Grejner-Brzezinska, E. Vazquez, L. Hothem
2006, Conference Paper, Proceedings of the Institute of Navigation - 19th International Technical Meeting of the Satellite Division, ION GNSS 2006
TransAntarctic Mountain DEFormation (TAMDEF) Monitoring Network is the NSF-sponsored OSU and USGS project, aimed at measuring crustal motion in the Transantarctic Mountains of Victoria Land using GPS carrier phase measurements. Station monumentation, antenna mounts, antenna types, and data processing strategies were optimized to achieve mm-level estimates for the rates of...
Some Key Features of the Strong-Motion Data from the M 6.0 Parkfield, California, Earthquake of 28 September 2004
A. Shakal, H. Haddadi, V. Graizer, K. Lin, M. Huang
2006, Bulletin of the Seismological Society of America (96)
The 2004 Parkfield, California, earthquake was recorded by an extensive set of strong-motion instruments well positioned to record details of the motion in the near-fault region, where there has previously been very little recorded data. The strong-motion measurements obtained are highly varied, with significant variations occurring over only a few...
Analysis of ecosystem controls on soil carbon source-sink relationships in the northwest Great Plains
Z. Tan, S. Liu, C.A. Johnston, J. Liu, L.L. Tieszen
2006, Global Biogeochemical Cycles (20) 1-9
Our ability to forecast the role of ecosystem processes in mitigating global greenhouse effects relies on understanding the driving forces on terrestrial C dynamics. This study evaluated the controls on soil organic C (SOC) changes from 1973 to 2000 in the northwest Great Plains. SOC source-sink relationships were quantified using...
Spectrophotometric properties of materials observed by Pancam on the Mars Exploration Rovers: 2. Opportunity
J. R. Johnson, W.M. Grundy, M.T. Lemmon, J.F. Bell III, M. J. Johnson, R. Deen, R. E. Arvidson, W. H. Farrand, E. Guinness, A. G. Hayes, Kenneth E. Herkenhoff, F. Seelos, J. Soderblom, S. Squyres
2006, Journal of Geophysical Research E: Planets (111)
The Panoramic Camera (Pancam) on the Mars Exploration Rover Opportunity acquired visible/near‐infrared multispectral observations of soils and rocks under varying viewing and illumination geometries that were modeled using radiative transfer theory to improve interpretations of the microphysical and surface scattering nature of materials in Meridiani Planum. Nearly 25,000 individual measurements...
Emplacement of the Kodiak batholith and slab-window migration
David W. Farris, Peter J. Haeussler, Richard Friedman, Scott R. Paterson, R. W. Saltus, Robert A. Ayuso
2006, Geological Society of America Bulletin (118) 1360-1376
The Kodiak batholith is one of the largest, most elongate intrusive bodies in the forearc Sanak-Baranof plutonic belt located in southern Alaska. This belt is interpreted to have formed during the subduction of an oceanic spreading center and the associated migration of a slab window. Individual plutons of the Kodiak...
Rupture models for the A.D. 900-930 Seattle fault earthquake from uplifted shorelines
Uri S. ten Brink, J. Song, R.C. Bucknam
2006, Geology (34) 585-588
A major earthquake on the Seattle fault, Washington, ca. A.D. 900-930 was first inferred from uplifted shorelines and tsunami deposits. Despite follow-up geophysical and geological investigations, the rupture parameters of the earthquake and the geometry of the fault are uncertain. Here we estimate the fault geometry, slip direction, and magnitude...
Effects of long-term water table drawdown on evapotranspiration and vegetation in an arid region phreatophyte community
D.J. Cooper, J.S. Sanderson, D.I. Stannard, D.P. Groeneveld
2006, Journal of Hydrology (325) 21-34
Evapotranspiration rates and the ground water component of evapotranspiration at a site in Colorado's San Luis Valley that is dominated by shrubby phreatophytes (greasewood and rabbitbrush) were compared before and after a water table drawdown. Evapotranspiration (ET) rates at the site were first measured in 1985-1987 (pre-drawdown) when the mean...
Using experimental and geospatial data to estimate regional carbon sequestration potential under no-till management
Z. Tan, R. Lal, S. Liu
2006, Soil Science (171) 950-959
Conservation management of croplands at the plot scale has demonstrated a great potential to mitigate the greenhouse effect through sequestration of atmospheric carbon (C) into soil. This study estimated the potential of soil to sequester C through the conversion of croplands from conventional tillage (CT) to no-till (NT) in the...
Using models to manage systems subject to sustainability indicators
M. C. Hill
2006, Conference Paper, IAHS-AISH Publication
Mathematical and numerical models can provide insight into sustainability indicators using relevant simulated quantities, which are referred to here as predictions. To be useful, many concerns need to be considered. Four are discussed here: (a) mathematical and numerical accuracy of the model; (b) the accuracy of the data used in...
Longitudinal hydraulic analysis of river‐aquifer exchanges
C.P. Konrad
2006, Water Resources Research (42)
A longitudinal analysis of transient flow between a river and an underlying aquifer is developed to calculate flow rates between the river and the aquifer and the location of groundwater seepage into the river as it changes over time. Two flow domains are defined in the analysis: an upstream domain...
Modelling and understanding volcanic processes using high-quality seismological data
Bernard A. Chouet
2006, Géosciences (2006) 56-63
At an active volcano, Very-Long-Period (VLP) seismicity (with typical periods in the range 2-100 s) reflects pressure fluctuations resulting from unsteady mass transport in the sub-surface plumbing system, and hence provides a glimpse of the internal dynamics of the volcanic edifice. Understanding the fundamental fluid-flow mechanisms involved in the...