Conference Papers
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Browse almost 5,000 conference papers authored by our scientists and refine search by topic, location, year, and advanced search.
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Census methodologies of Black-legged Kittiwakes in Glacier Bay National Park
Black-legged Kittiwakes (Rissa tridactyla) have recently experienced widespread population declines and frequent colony failures throughout the North Pacific. At Glacier Bay National Park, the Margerie Glacier colony was censused visually in 1991 through 1993. In 1993 a new photographic census technique was also tested to assess its feasibility, accuracy, and ease of use, Three years of monitoring
Authors
Elizabeth Ross Hooge
Channel degradation in southeastern Nebraska Rivers
Many stream channels in southeastern Nebraska were dredged and straightened during 1904-15. The resulting channels were both shorter and steeper than the original channels. Tests for time trends were conducted using the nonparametric Kendall tau test to see if the channels have responded to these changes. Tests were conducted on the stages associated with specific discharges and on measurement cha
Authors
Kenneth L. Wahl, Linda S. Weiss
Comparative behavior and dietary effects in early life stages of American sturgeons
No abstract available at this time
Authors
R. M. Ross, R. M. Bennett
Contraction scour at a bridge over Wolf Creek, Iowa
Contraction scour at the State Highway 14 bridge over Wolf Creek in south-central Iowa was caused by a large flood on September 14 and 15, 1992. The bridge is a 30.5-m, single-span steel structure supported by vertical-wall concrete abutments with wingwalls. Approximately 6 meters of scour resulted from the flood. The peak discharge was estimated by water-surface profile analysis to be 2,200 cubic
Authors
Edward E. Fischer
Correlation of Ordovician rocks of northern Alaska
The Ordovician sequences presented in this report were chosen to cover a range of depositional and structural settings found in northern Alaska. Consequently, the quality of lithostratigraphic, paleontologic, and sedimentologic data is variable. Until 1982, Ordovician rocks in northern Alaska were known only from a few, widely separated localities. Since then, several hundred Ordovician conodont c
Authors
Anita G. Harris, Julie A. Dumoulin, John E. Repetski, Claire Carter
Creating habitat for endangered species: use of restored riparian woodlands by least Bell's vireos
No abstract available at this time
Authors
B.E. Kus
Depth to pre-Cenozoic basement in Southwest Nevada
An iterative procedure based on gravity data, surface geology, and an estimated density-depth function was used to estimate the depth to pre-Cenozoic basement at Yucca Mountain and vicinity.
Authors
V. E. Langenheim, D. A. Ponce
Diet study of Atlantic sturgeon in marine waters
No abstract available at this time
Authors
J. Johnson, D. Dropkin
Digital photogrammetry at the U.S. Geological Survey
The U.S. Geological Survey is converting its primary map production and revision operations to use digital photogrammetric techniques. The primary source of data for these operations is the digital orthophoto quadrangle derived from National Aerial Photography Program images. These digital orthophotos are used on workstations that permit comparison of existing vector and raster data with the ortho
Authors
Clifford W. Greve
Discrete fracture modeling-ESF North Portal Area, Yucca Mountain Nevada
Statistical parameters from three-dimensional fracture network and hydraulic parameters were developed to be used in site scale models. This approach utilizes geometric fracture models and assess their impact on flow characteristics and parameters. Laboratory and field-testing data will be integrated to calibrate the flow models and to determine sensitivities of the system.
Authors
Lawrence O. Anna
Effect of ground-water/surface-water interactions on nitrate concentrations in discharge from the South Platte River alluvial aquifer, Colorado
Concentrations of dissolved nitrate in recharge-area water from a 200-km2 segment of the South Platte River alluvial aquifer near Greeley, Colorado, range from less than 0.1 to 58 mg/l as nitrogen, and the median concentration is 26 mg/l as nitrogen. Hydraulic-head data indicate that this nitrate-enriched ground water move toward the South Platte River. However, the median concentration of nitrate
Authors
P. B. McMahon, J.K. Böhlke
Effects of agricultural, industrial, and municipal pollutants on wetlands and wildlife and wildlife health
Wetlands accumulate pollutants from adjacent areas through intentional discharge of sewage or industrial wastes, runoff of agricultural fertilizers and pesticides, and discharge from municipal storm drains. Coastal wetlands receive more pollutants indirectly as the endpoint for upland drainage systems and directly through petroleum spills and insect abatement. Wetlands that serve as evaporation
Authors
Kathryn A. Converse