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An understanding of the magnitude and frequency of low-flow discharges is an important part of protecting surface-water resources and planning for municipal and industrial economic expansion. Low-flow characteristics are summarized for 12 continuous-record gaging stations and 44 partial-record measuring sites in the Rocky River basin in North Carolina. Records of...

Most procedures for routinely locating earthquake hypocenters within a local network are constrained to using laterally homogeneous velocity models to represent the Earth's crustal velocity structure. As a result, earthquake location errors may arise due to actual lateral variations in the Earth's velocity structure. Station corrections can be used to...

The USGS FORSPAN model is designed for the assessment of continuous accumulations of crude oil, natural gas, and natural gas liquids (collectively called petroleum). Continuous (also called ?unconventional?) accumulations have large spatial dimensions and lack well defined down-dip petroleum/water contacts. Oil and natural gas therefore are not localized by buoyancy in water in these...

Outflow from Table Rock Lake and other White River reservoirs support a cold-water trout fishery of substantial economic yield in south-central Missouri and north-central Arkansas. The Missouri Department of Conservation has requested an increase in existing minimum flows through the Table Rock Lake Dam from the U.S. Army Corps of...

An atmospheric correction algorithm developed for the 1 km Advanced Very High Resolution Radiometer (AVHRR) global land dataset was modified to include a near real-time total column water vapour data input field to account for the natural variability of atmospheric water vapour. The real-time data input field used for this...

We used analytic and simulation models to determine the ecological conditions favoring evolution of a matrotrophic fish from a lecithotrophic ancestor given a complex set of trade‐offs. Matrotrophy is the nourishment of viviparous embryos by resources provided between fertilization and parturition, while lecithotrophy describes embryo nourishment provided before fertilization. In...

We have studied the effects of local topography and canopy structure on turbulent flux measurements at a site located in mountainous terrain within a subalpine, coniferous forest. Our primary aim was to determine whether the complex terrain of the site affects the accuracy of eddy flux measurements from a practical...

No abstract available. ...

A transform fault is modeled as a vertical cut through an elastic layer (schizosphere) of thickness overlying a viscous substrate (plastosphere). We consider a steady transform motion accommodated in the schizosphere wholly by slip on the fault and in the plastosphere, insofar as possible, by viscous flow. For the case...

This report describes modifications to a U.S. Geological Survey (USGS) threedimensional solute-transport model (MODFLOWGWT), which is incorporated into the USGS MODFLOW ground-water model as the Ground- Water Transport (GWT) Process. The modifications improve the capability of MODFLOW-GWT to accurately simulate solute transport in simulations that represent a nonzero flux across an aquifer boundary. In such situations, the new Boundary Flux...

Six North Slope petroleum systems are identified, described, and mapped using oil-to-oil and oil-to-source rock correlations, pods of active source rock, and overburden rock packages. To map these systems, we assumed that: a) petroleum source rocks contain 3.2 wt. % organic carbon (TOC); b) immature oil-prone source rocks have hydrogen...

Resource assessment of the North Slope of Alaska by the U. S. Geological Survey includes evaluation of the petroleum source potential of Mesozoic and Cenozoic rocks using the delta log R technique (Passey and others, 1990). Porosity and resistivity logs are used in combination with thermal maturity data to produce...

Representative compaction curves for the principle lithologies are essential input for reliable models of basin history. Compaction curves influence estimates of maximum burial and erosion. Different compaction curves may produce significantly different thermal histories. Default compaction curves provided by basin modeling packages may or may not be a good proxy...

The U.S. Geological Survey initiated an effort to model north Alaskan petroleum systems. The geographic and geologic basis for modeling systems is provided by a set of regional digital maps that allow evaluation of the widest possible extent of each system. Accordingly, we laid out a rectangular map grid 1300...

The Alaska Volcano Observatory (AVO), a cooperative program of the U.S. Geological Survey, the Geophysical Institute of the University of Alaska Fairbanks, and the Alaska Division of Geological and Geophysical Surveys, has maintained seismic monitoring networks at historically active volcanoes in Alaska since 1988 (Power and others, 1993; Jolly and...

This geologic database of the Redlands 7.5' quadrangle was prepared by the Southern California Areal Mapping Project (SCAMP), a regional geologic-mapping project sponsored jointly by the U.S. Geological Survey and the California Geological Survey. The database was developed as a contribution to the National Cooperative Geologic Mapping Program's National Geologic...

These maps present the results of assessments of peak discharges that can potentially be generated by debris flows issuing from the basins burned by the Missionary Ridge fire of June 9 through July 14, 2002, near Durango, Colorado. The maps are based on a regression model for debris-flow peak discharge...

Ground penetrating radar (GPR) is used to track a dense non-aqueous phase liquid (DNAPL) injection in a laboratory sand tank. Before data reduction, GPR data provide a qualitative measure of DNAPL saturation and movement. One-dimensional (1D) GPR modeling provides a quantitative interpretation of DNAPL volume within a given thickness during...

These maps present the results of assessments of peak discharges that can potentially be generated by debris flows issuing from the basins burned by the Coal Seam fire of June and July 2002, near Glenwood Springs, Colorado. The maps are based on a regression model for debris-flow peak discharge normalized...

This aeromagnetic map covers the southern portion of San Francisco Bay, the Santa Clara Valley and surrounding mountains, part of which has been modelled in threedimensions (Jachens and other, 2001). The magnetic anomaly map has been compiled from existing digital data. Data was obtained from six aeromagnetic surveys that were...

The Western Earth Surface Processes Team (WESPT) of the U.S. Geological Survey (USGS) conducts geologic mapping and related topical earth science studies in the western United States. This work is focused on areas where modern geologic maps and associated earth-science data are needed to address key societal and environmental issues...

The San Bernardino 30'x60' quadrangle, southern California, is diagonally bisected by the San Andreas Fault Zone, separating the San Gabriel and San Bernardino Mountains, major elements of California's east-oriented Transverse Ranges Province. Included in...

Glacial Lake Missoula, impounded by the Purcell Trench lobe of the late Pleistocene Cordilleran Icesheet, repeatedly breached its ice dam, sending floods as large as 2,500 cubic kilometers racing across the Channeled Scabland and down the Columbia River valley to the Pacific Ocean. Peak discharges for some floods exceeded 20...

The complex petroleum province of the Alaskan North Slope contains six petroleum systems (Magoon and others, this session). Source rocks for four of these systems include the Hue-gamma ray zone (Hue-GRZ), pebble shale unit, Kingak Shale, and Shublik Formation. Geochemical data for these source rocks are investigated in greater detail...