Search Results

Annual loads and flow-adjusted concentration trends were estimated by use of water-quality and streamflow data collected from 1990 through 1999 at monitoring stations on two tributaries to Chesapeake Bay in Virginia—James River at Cartersville, Va., and Rappahannock River near Fredericksburg, Va. The effects of storm-sampling frequency on the accuracy and...

Water-quality and flow data from 31 sites in nontidal portions of the Chesapeake Bay Basin were analyzed to document annual nutrient and sediment loads and trends for the period 1985 through 1999 as part of an annual reevaluation and reporting for the Chesapeake Bay Program. Annual loads were estimated by...

This paper presents 25 new 40Ar/39Ar dates from the main calc-alkaline ash-flow sheets and related younger plutons of the western San Juan volcanic field, the ash-flow sheets of the Lake City caldera cycle, and veins and other altered rocks in the Lake City region. The goal of the study was...

The Red River of the North is a complex river system in the north-central plains of the United States. The river continues to impact the people and property within its basin. During the spring of 2001, major flooding occurred for the second time in four years on the Red River...

This report presents the results of the U.S. Geological Survey's analytical evaluation program for six standard reference samples -- T-163 (trace constituents), M-156 (major constituents), N-67 (nutrient constituents), N-68 (nutrient constituents), P-35 (low ionic strength constituents), and Hg-31 (mercury) -- that were distributed in October 2000 to 126 laboratories enrolled...

Chemical loads from ground water to the Grand Calumet River and the Indiana Harbor Canal in northwestern Indiana were estimated to aid in determining the total maximum daily load. Data from two previous studies, completed in 1987 and 1993, were used to compute loads. The first study included a ground-water-flow...

The Red River Aluminum site near Stamps, Arkansas, contains waste piles of salt cake and metal byproducts from the smelting of aluminum. The waste piles are subjected to about 50 inches of rainfall a year, resulting in the dissolution of the salts and metal. To assess the potential threat to...

Arnold Air Force Base (AAFB) occupies about 40,000 acres in Coffee and Franklin Counties, Tennessee. Numerous site-specific ground-water contamination investigations have been conducted at designated solid waste management units (SWMU?s) at AAFB. Several synthetic volatile organic compounds (VOC?s), primarily chlorinated solvents, have been identified in groundwater samples collected from monitoring...

This digital map database, compiled from previously published and unpublished data, and new mapping by the authors, represents the general distribution of bedrock and surficial deposits of the Silver lake 7.5 minute quadrangle. The database delineates map units that are identified by general age and lithology following the stratigraphic...

A new effort is underway to compile an upgraded digital magnetic anomaly data base and map for the North American continent by 2002. This program is a joint effort by the Geological Survey of Canada (GSC), the U.S. Geological Survey (USGS), and Consejo de Recursos Minerales...

Floods can cause water-quality problems because of the large amounts of contaminants (sediment, nutrients, pesticides, and bacteria) that can be transported by floodwaters. during the flood on the Upper Mississippi River in 2001, water-quality and water-quality data were collected during near-record streamflow. This is the first time that samples for...

Nearshore bathymetry data collected along the US Pacific Northwest is analyzed to determine relationships between nearshore morphology and shoreline change at a variety of spatial scales. Sandbar properties are compared at three sites, locations separated by tens of kilometers but subject to similar hydrodynamic forcing and having like sediment characteristics....

Counts of uniquely identified individuals in a population offer opportunities to estimate abundance. However, for various reasons such counts may be burdened by heterogeneity in the probability of being detected. Theoretical arguments and empirical evidence demonstrate that the negative binomial distribution (NBD) is a useful characterization for counts from biological...

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database...

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database...

This digital map database is compiled from unpublished data and new mapping by the authors, represents the general distribution of surficial and bedrock geology in the mapped area. Together with the accompanying pamphlet, it provides current information on the geologic structure and stratigraphy of the area. The database...

The radiated seismic energies (ES) of 980 shallow subduction-zone earthquakes with magnitudes ? 5.8 are used to examine global patterns of energy release and apparent stress. In contrast to traditional methods which have relied upon empirical formulas, these energies are computed through direct spectral analysis of broadband seismic waveforms. Energy...

This report provides statistical summaries of rainfall, streamflow, suspended-sediment, and water-quality data collected in the Halawa, Haiku, and Kaneohe drainage basins before, during, and after construction of the H-3 Highway on the island of Oahu, Hawaii. Methods of data collection also are described. Data collected during water years 1983 through...

This CD-ROM contains photographs and sediment sample analyses of the sea floor obtained at 142 sites in western Massachusetts Bay (Figure 1) during a research cruise (USGS cruise ISBL99024) aboard the Fishing Vessel (FV) Isabel S. (Figure 2) conducted July 18-21, 1999. These photographs and samples provide critical ground...

This digital map database was compiled from previously published and unpublished data by the author and USGS colleagues, and from published maps by others, as indicated in figure 3 on the map sheet. A pamphlet included with the map provides a brief discussion of the geology of the quadrangle,...

Stormwater and streamflow in Maricopa County were monitored to (1) describe the physical, chemical, and toxicity characteristics of stormwater from areas having different land uses, (2) describe the physical, chemical, and toxicity characteristics of streamflow from areas that receive urban stormwater, and (3) estimate constituent loads in stormwater. Urban stormwater...