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The Bridge Timber Mountain area in south-central La Plata County, southwestern Colorado lies mostly in the northwestern part of the Central San Juan Basin but contains a segment of the bounding Hogback 'monocline' and Four-Corners platform. The area contains rocks of late Cretaceous through early Eocene age, as well as Pliocene, Pleistocene, and Recent terrace and pediment gravels. The Pictured Cliffs sandstone of late Montana age is the latest marine formation present. Retreat of the Cretaceous seas from the area marked the beginning of Laramide orogenic activity and the earliest stages of deformation which produced the modern San Juan Basin. The Fruitland formation and Kirtland shale were deposited in brackish...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Executive Summary This 2006 annual report details the first season of a 2-year study documenting western yellow-billed cuckoo (Coccyzus americanus occidentalis) distribution, abundance, and habitat use throughout the Lower Colorado River Multi-Species Conservation Plan boundary area. We conducted cuckoo surveys at 55 sites within 17 areas, between 11 June and 13 September. The 243 visits across all sites yielded 180 yellow-billed cuckoo detections. Cuckoos were detected at 27 of the 55 sites, primarily at the Bill Williams River National Wildlife Refuge AZ sites (n = 117 detections) and the Grand Canyon National Park-Lake Mead National Recreation Area AZ delta sites (n = 29 detections). There were also cuckoos at...
Categories: Publication; Types: Citation; Tags: Open-File Report
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After the devastating floods caused by Hurricane Mitch in 1998, maps of the areas and depths of 50-year-flood inundation at 15 municipalities in Honduras were prepared as a tool for agencies involved in reconstruction and planning. This report, which is one in a series of 15, presents maps of areas in the municipality of Nacaome that would be inundated by 50-year floods on Rio Nacaome, Rio Grande, and Rio Guacirope. Geographic Information System (GIS) coverages of the flood inundation are available on a computer in the municipality of Nacaome as part of the Municipal GIS project and on the Internet at the Flood Hazard Mapping Web page (http://mitchnts1.cr.usgs.gov/projects/floodhazard.html). These coverages allow...
Categories: Publication; Types: Citation; Tags: Open-File Report
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This report presents surface water and surface (top 0-2 cm) sediment geochemical data collected during 2005-2006, as part of a larger study of mercury (Hg) dynamics in seasonal and permanently flooded wetland habitats within the lower Sacramento River basin, Yolo County, California. The study was conducted in two phases. Phase I represented reconnaissance sampling and included three locations within the Cache Creek drainage basin; two within the Cache Creek Nature Preserve (CCNP) and one in the Cache Creek Settling Basin (CCSB) within the creek's main channel near the southeast outlet to the Yolo Bypass. Two additional downstream sites within the Yolo Bypass Wildlife Area (YBWA) were also sampled during Phase I,...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Lost River suckers Deltistes luxatus and shortnose suckers Chasmistes brevirostris , listed as endangered in 1988 under the Endangered Species Act, have shown infrequent recruitment into adult populations in Upper Klamath Lake (NRC 2004). In an effort to understand the causes behind and provide management solutions to apparent recruitment failure, a number of studies have been conducted including several on larval and juvenile sucker habitat use. Near-shore areas in Upper Klamath Lake with emergent vegetation, especially those near the mouth of the Williamson River, were identified as important habitat for larval suckers (Cooperman and Markle 2000; Reiser et al. 2001). Terwilliger et al. (2004) characterized primary...
Categories: Publication; Types: Citation; Tags: Open-File Report
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The Christmas copper deposit, located in southern Gila County, Arizona, is part of the major porphyry copper province of southwestern North America. Although Christmas is known for skarn deposits in Paleozoic carbonate rocks, ore-grade porphyry-type copper mineralization also occurs in a composite granodioritic intrusive complex and adjacent mafic volcanic country rocks. This study considers the nature, distribution, and genesis of alteration-mineralization in the igneous rock environment at Christmas. At the southeast end of the Dripping Spring Mountains, the Pennsylvanian Naco Limestone is unconformably overlain by the Cretaceous Williamson Canyon Volcanics, a westward-thinning sequence of basaltic volcanic breccia...
Categories: Publication; Types: Citation; Tags: Open-File Report
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The section 23 mine is one of about 18 large uranium mines opened in sandstones of the fluvial Westwater Canyon Member of the Jurassic Morrison Formation in the Ambrosia Lake mining district during the early 1960s. The Ambrosia Lake district is one of several mining districts within the Grants mineral belt, an elongate zone containing many uranium deposits along the southern flank of the San Juan basin. Two distinct types of ore occur in the mine. Primary ore occurs as peneconcordant layers of uranium-rich authigenic organic matter that impregnates parts of the reduced sandstone host rocks and which are typically elongate in an east-southeast direction subparallel both to the sedimentary trends and to the present-day...
Categories: Publication; Types: Citation; Tags: Open-File Report
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RecologyTM, the primary San Francisco waste-disposal entity, is proposing to develop a Class 1 landfill near Jungo, Nevada. The proposal calls for the landfill to receive by rail about 20,000 tons of waste per week for up to 50 years. On September 22, 2009, the Interior Appropriation (S.A. 2494) was amended to require the U.S. Geological Survey to evaluate the proposed Jungo landfill site for: (1) potential water-quality impacts on nearby surface-water resources, including Rye Patch Reservoir and the Humboldt River; (2) potential impacts on municipal water resources of Winnemucca, Nevada; (3) locations and altitudes of aquifers; (4) how long it will take waste seepage from the site to contaminate local aquifers;...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Watersheds play many important roles in the carbon cycle: (1) they are a site for both terrestrial and aquatic carbon dioxide (CO2) removal through photosynthesis; (2) they transport living and decomposing organic carbon in streams and groundwater; and (3) they store organic carbon for widely varying lengths of time as a function of many biogeochemical factors. Using the U.S. Geological Survey (USGS) Spatially Referenced Regression on Watershed Attributes (SPARROW) model, along with long-term monitoring data on total organic carbon (TOC), this research quantitatively estimates the sources, transport, and fate of the long-term mean annual load of TOC in streams of the conterminous United States. The model simulations...
Categories: Publication; Types: Citation; Tags: Open-File Report
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In the summer of 2007, the U.S. Geological Survey (USGS) began an exploration geochemical research study over the Pebble porphyry copper-gold-molydenum (Cu-Au-Mo) deposit in southwest Alaska. The Pebble deposit is extremely large and is almost entirely concealed by tundra, glacial deposits, and post-Cretaceous volcanic and volcaniclastic rocks. The deposit is presently being explored by Northern Dynasty Minerals, Ltd., and Anglo-American LLC. The USGS undertakes unbiased, broad-scale mineral resource assessments of government lands to provide Congress and citizens with information on national mineral endowment. Research on known deposits is also done to refine and better constrain methods and deposit models for...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Clear Creek, one of the major tributaries of the upper Sacramento River, drains the eastern Trinity Mountains. Alluvial plain and terrace gravels of lower Clear Creek, at the northwest edge of the Sacramento Valley, contain placer gold that has been mined since the Gold Rush by various methods including hydraulic mining and dredging. In addition, from the 1950s to the 1980s aggregate-mining operations removed gravel from the lower Clear Creek flood plain. Since Clear Creek is an important stream for salmon production, a habitat restoration program is underway to repair damage from mining and improve conditions for spawning. This program includes moving dredge tailings to increase the area of spawning gravel and...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Water samples were collected from 7 production wells and 28 private residential wells in central New York from August through December 2007 and analyzed to characterize the chemical quality of groundwater. Seventeen wells are screened in sand and gravel aquifers, and 18 are finished in bedrock aquifers. The wells were selected to represent areas of greatest groundwater use and to provide a geographical sampling from the 5,799-square-mile study area. Samples were analyzed for 6 physical properties and 216 constituents, including nutrients, major inorganic ions, trace elements, radionuclides, pesticides, volatile organic compounds, phenolic compounds, organic carbon, and 4 types of bacteria. Results indicate that...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Saudi Arabia's northern sand seas are composed dominantly of stable dune systems, even though the modern climate is arid. The stable dunes are large and support a sparse semidesert vegetation. Active dunes are small and commonly confined to the crests of stable dunes; they comprise less than 5 percent of the dunes in the sand seas. Both the stability of the major dune systems and the small percentage of active dunes in the modern environment indicate a significant decrease in the average velocity and frequency of sand-moving winds since the time of stable-dune deposition. Comparison of modern wind directions with dune trends indicates that southwesterly winds responsible for dune formation in the southern and western...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Introduction The ability to predict the distribution of submersed aquatic vegetation in the Upper Mississippi River on the basis of physical or chemical variables is useful to resource managers. Wildlife managers have a keen interest in advanced estimates of food quantity such as American wildcelery (Vallisneria americana) population status to give out more informed advisories to hunters before the fall hunting season. Predictions for distribution of submerged aquatic vegetation beds can potentially increase hunter observance of voluntary avoidance zones where foraging birds are left alone to feed undisturbed. In years when submersed aquatic vegetation is predicted to be scarce in important wildlife habitats, managers...
Categories: Publication; Types: Citation; Tags: Open-File Report
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The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, is studying the hydrogeology and water quality of aquifers in the vicinity of Belvidere, Boone County, Ill. This report presents available well-construction, hydrogeologic, and ground-water-quality data compiled into a geographic information system (GIS) data base for this study. General instructions on manipulation and suggested applications of the GIS data base are included. Three plates show the location and type of wells and distribution of ground-water-quality data within the study area. The data are intended to aid investigators in present and possible future hydrogeologic studies in the vicinity of Belvidere. The data...
Categories: Publication; Types: Citation; Tags: Open-File Report
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With costs of natural disasters skyrocketing and populations increasingly settling in areas vulnerable to natural hazards, society is challenged to better allocate its limited risk-reduction resources. In 2000, Congress passed the Disaster Mitigation Act, amending the Robert T. Stafford Disaster Relief and Emergency Assistance Act (Robert T. Stafford Disaster Relief and Emergency Assistance Act, Pub. L. 93-288, 1988; Federal Emergency Management Agency, 2002, 2008b; Disaster Mitigation Act, 2000), mandating that State, local, and tribal communities prepare natural-hazard mitigation plans to qualify for pre-disaster mitigation grants and post-disaster aid. The Federal Emergency Management Agency (FEMA) was assigned...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Degradation of ground-water quality has been identified in an area of the north-central part of the town of Cheshire, Connecticut. An investigation by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, was done during 1994-95 to characterize the unconsolidated glacial deposits and the sedimentary bedrock, integrate the local geohydrologic conditions with the regional geohydrologic system, and develop a conceptual understanding of ground-water flow in the study area. A regional ground-water-flow model developed for the region near the study area indicates that perennial streams, including Judd Brook and the Tenmile River, form hydrologic divides that separate the larger region...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Low-level radioactive solid waste has been buried in trenches at a site near Beatty, Nevada, since 1962. In 1976, as part of a national program, the U.S. Geological Survey began a study of the geohydrology of the waste burial site to provide a basis for estimating the potential for radionuclide migration in the unsaturated zone beneath the waste burial trenches. Data collected include meteorological information for calibration of a long-term water budget analysis, soil moisture profiles, soil water potentials, and hydraulic properties of representative unsaturated sediment samples to a depth of about 10 m. The waste burial facility is in the northern Amargosa Desert about 170 km northwest of Las Vegas, NV. The region...
Categories: Publication; Types: Citation; Tags: Open-File Report
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Renewed copper exploration by Alaska Copper Mines, Incorporated, at the Nelson and Radovan prospects, Nizina district, Alaska, led the Geological Survey in 1951 to map in detail the Nelson fault block, and to re-examine the old workings. In addition, two new prospects were studied. The Nelson fault block is cut by many dominantly strike-slip faults of small displacement, and by bedding faults. Slickensided chalcocite shows post-mineral movement, and chalcocite veinlet in a filled solution cavity indicates that some of the chalcocite is secondary, perhaps very recent. Structural relations indicate two overthrust faults cut the block. The Radovan Greenstone prospect shows massive chalcocite, up to 3 feet wide, in...
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Prospect Gulch is a major source of iron, aluminum, zinc, and other metals to Cement Creek. Information is needed to prioritize remediation and develop strategies for cleanup of historical abandoned mine sites in Prospect Gulch. Chemical-constituent loads were determined in Prospect Gulch, a high-elevation alpine stream in southwestern Colorado that is affected by natural acid drainage from weathering of hydro-thermally altered igneous rock and acidic metal-laden discharge from historical abandoned mines. The objective of the study was to identify metal sources to Prospect Gulch. A tracer solution was injected into Prospect Gulch during water-quality sampling so that loading of geochemical constituents could be...
Categories: Publication; Types: Citation; Tags: Open-File Report