Conference Papers
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Environmental history and tephrostratigraphy at Carp Lake, southwestern Columbia Basin, Washington, USA
Sediment cores from Carp Lake provide a pollen record of the last ca. 125,000 years that helps disclose vegetational and climatic conditions from the present day to the previous interglaciation (120-133 ka). The core also contained 15 tephra layers, which were characterised by electron-microprobe analysis of volcanic glass shards. Identified tephra include Mount St. Helens Ye, 3.69 ka; Mazama ash
Authors
C. Whitlock, A.M. Sarna-Wojcicki, P. J. Bartlein, R.J. Nickmann
Estimation of potential loss of two pesticides in runoff in Fillmore County, Minnesota using a field-scale process-based model and a geographic information system
In assessing the occurrence, behavior, and effects of agricultural chemicals in surface water, the scales of study (i.e., watershed, county, state, and regional areas) are usually much larger than the scale of agricultural fields, where much of the understanding of processes has been developed. Field-scale areas are characterized by relatively homogeneous conditions. The combination of process-bas
Authors
Paul D. Capel, Zhang Hua
Etiology and pathogenesis of skin ulcers in menhaden, Brevoortia tyrannis: does Pfiesteria piscicida play a role?
The toxic dinoflagellate, Pfiesteria piscicida, is widely blamed for adverse human health effects, acute fish kills and skin lesion events in fishes, particularly menhaden, Brevoortia tyrannis, inhabiting coastal waters from Delaware to North Carolina, USA. In response, we initiated studies to clarify the etiology and pathogenesis of presumed 'Pfiesteria-specific' menhaden skin lesions. Histopatho
Authors
V. Blazer, W. K. Vogelbein, C. Densmore, H. Kator, D. Zwerner, J. Lilley
Evolution of harvest management for North American waterfowl: Selective pressures and preadaptations for adaptive harvest management
No abstract available.
Authors
James D. Nichols
Follow-ons to the KidSAT/EarthKAM student remote sensing program
The KidSAT/EarthKAM program is a NASA educational initiative that allows students to develop and operate a remote sensing space program. The first phase of the program consisted of a student developed camera that is flown on Space Shuttle missions in the nadir window. A network of students develop a series of image acquisition requests, based on approved science proposals, that are combined into a
Authors
Grant R. Mah
Formation evaluation of gas hydrate-bearing marine sediments on the Blake Ridge with downhole geochemical log measurements
The analyses of downhole log data from Ocean Drilling Program (ODP) boreholes on the Blake Ridge at Sites 994, 995, and 997 indicate that the Schlumberger geochemical logging tool (GLT) may yield useful gas hydrate reservoir data. In neutron spectroscopy downhole logging, each element has a characteristic gamma ray that is emitted from a given neutron-element interaction. Specific elements can be
Authors
T. S. Collett, R. F. Wendlandt
Formation of natural gas hydrates in marine sediments. Gas hydrate growth and stability conditioned by host sediment properties
The stability conditions of submarine gas hydrates (methane clathrates) are largely dictated by pressure, temperature, gas composition, and pore water salinity. However, the physical properties and surface chemistry of the host sediments also affect the thermodynamic state, growth kinetics, spatial distributions, and growth forms of clathrates. Our model presumes that gas hydrate behaves in a way
Authors
M. B. Clennell, P. Henry, M. Hovland, J.S. Booth, W.J. Winters, M. Thomas
Gas content and composition of gas hydrate from sediments of the southeastern North American continental margin
Gas hydrate samples were recovered from four sites (Sites 994, 995, 996, and 997) along the crest of the Blake Ridge during Ocean Drilling Program (ODP) Leg 164. At Site 996, an area of active gas venting, pockmarks, and chemosynthetic communities, vein-like gas hydrate was recovered from less than 1 meter below seafloor (mbsf) and intermittently through the maximum cored depth of 63 mbsf. In cont
Authors
T.D. Lorenson, T. S. Collett
Gas hydrate and humans
The potential effects of naturally occurring gas hydrate on humans are not understood with certainty, but enough information has been acquired over the past 30 years to make preliminary assessments possible. Three major issues are gas hydrate as (1) a potential energy resource, (2) a factor in global climate change, and (3) a submarine geohazard. The methane content is estimated to be between 1015
Authors
K. A. Kvenvolden
Genetic diversity patterns and evolution of an aquatic rhabdovirus
No abstract available.
Authors
Gael Kurath, R.M. Troyer, Eric Anderson, E.J. Emmenegger
Geohydrologic assessment of crystalline bedrock for the New York City water-tunnel project by use of advanced borehole-geophysical methods
No abstract available.
Authors
Frederick Stumm, Frederick L. Paillet, John H. Williams, John W. Lane
Geophysical, archaeological and historical evidence support a solar-output model for climate change
Although the processes of climate change are not completely understood, an important causal candidate is variation in total solar output. Reported cycles in various climate-proxy data show a tendency to emulate a fundamental harmonic sequence of a basic solar-cycle length (11 years) multiplied by 2(N) (where N equals a positive or negative integer). A simple additive model for total solar-output v
Authors
C. A. Perry, K.J. Hsu