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A three-dimensional groundwater flow and solute transport model was calibrated to a plume of water described by measurements of δ18O and used to calculate groundwater inflow and outflow rates at a lake in northern Wisconsin. The flow model was calibrated to observed hydraulic gradients and estimated recharge rates. Calibration of...

Bed sediments of the San Joaquin River and its tributaries were sampled during October 7–11, 1985, and analyzed for organochiorine pesticide residues in order to determine their areal distribution and to evaluate and prioritize needs for further study. Residues of DDD, DDE, DDT, and dieldrin are widespread in the fine-grained...

The development of geographic information systems (GIS) is a rapidly growing industry that supports natural resources, studies, land management, environmental analysis, and urban and transporation planning. The increasing use of computers for storing and analyzing earth science information has greatly expanded the demand for digital cartographic and geographic data. Digital...

The Earth Science Information Centers (ESIC) distribute digital cartographic/geographic data files produced by the U.S. Geological Survey (USGS) as part of the National Mapping Program. The data files are grouped into four basic types. The first type, called a Digital Line Graph (DLG), is line map information in digital form....

This annual hydrologic data report of New Mexico is one of a series of annual reports that document hydrologic data gathered frOm the u.s. Geological Survey's surface- and ground-water data-collection networks in each State, Puerto Rico, and the Trust Territories. These records of streamflow, ground-water levels, and water quality provide the...

Previous paleomagnetic studies of accreted oceanic rocks within the Franciscan Complex of northern California have concluded that these rocks originated far to the south of their present positions with respect to the North American continent. Based on positive “fold” tests, the characteristic remanent magnetizations were inferred to predate accretion-related deformation...

Many species of seabirds exhibit delayed maturity and do not return to the natal colony to breed for several years after fledging. Capture-recapture studies are frequently conducted at such breeding colonies and often include marking of young birds. However, because of the absence of these birds from the...

Data from a 1986 field study of white-faced ibis (Plegadis chihi) nesting at Carson Lake, Nevada, were used to compare the utility of eggshell strength measurement and eggshell thickness as indicators of eggshell quality. The ibis population had a history of reproductive failure correlated with elevated egg concentrations of p, p'-DDE,...

We describe MULT, a flexible procedure for analysing ring recovery data. The procedure starts with parametric structures similar to, but more general than, those described by Brownie et al. (1985). Particular models, including those in Brownie et al. (1965), can be obtained by imposing constraints on the general parametric structures....

Reproductive parameters of American kestrels (Falco sparverius) were measured through two breeding seasons. Exposure to Kelthane® (containing no DDT-related compounds) at dietary concentrations of 0 (control), 1,3, 10 and 30 μg/g (wet weight) began in late November before, and continued through, the second season. Kelthane thinned eggshells and lowered the...

The route-regression method has been used in recent years to analyze data from roadside surveys. With this method, a population trend is estimated for each route in a region, then regional trends are estimated as a weighted mean of the individual route trends. This method can accurately incorporate data that...

Eight species of owls regularly occur and may breed in one or more of the southeastern states. Several additional northern or western species appear irregularly as accidentals or during years of southward incursions. In the Southeast, the most common and wide- spread owls are the common barn-owl, eastern screech-owl, great...

Most of the surveys presently used to estimate population trends on a large geographic scale depend upon repeated visits to a number of randomly selected routes or monitoring points. As these surveys cannot be analyzed by modeling annual mean densities among routes within a region, no natural annual index of...

We use North American Breeding Bird Survey data to estimate population trends for 1966-1988 for northern bobwhite (Colinus virginianus), ring-necked pheasant (Phasianus colchicus), and gray partridge (Perdix perdix). Bobwhite populations have undergone widespread declines, pheasant have undergone major declines in eastern North America with mixed trends elsewhere, gray partridge...

Water resources data for the 1989 water year for Mississippi consist of records of stage, discharge, and water quality of streams; stage, and water quality of lakes and reservoirs; and water levels and water quality of ground-water wells. This report contains records of water discharge at 81 gaging stations; stage...

Data relay systems on existing earth-orbiting satellites provide an inexpensive way to collect environmental data from numerous remote sites around the world. This technology could be used effectively for fundamental monitoring of most of the world's active volcanoes. Such global monitoring would focus attention on the most dangerous volcanoes that...

Recognition of North Pacific paleoceanographic events in the marginal Humboldt (Eel River) basin of northern California enables correlation of stratigraphic sections and development of a chronostratigraphy. Paleoclimatically related coiling shifts in Neogloboquadrina pachyderma (Ehrenberg) and benthic foraminiferal datums form the basis of the chronostratigraphy. Benthic foraminiferal datums are defined by the occurrence...

Conventional methods of measuring surface energy balance are point measurements and represent only a small area. Remote sensing offers a potential means of measuring outgoing fluxes over large areas at the spatial resolution of the sensor. The objective of this study was to estimate net radiation (Rn) and soil heat...

GLIMPCE deep Seismic reflection profiles across the Midcontinent Rift System beneath Lake Superior reveal a central asymmetric rift with an enormous thickness of volcanic and sedimentary rocks. True amplitude cmp-processing, poststack and prestack migration and forward modelling are used to improve images of steeply dipping faults, unconformities and other discontinuities...

A unified, multidiscipline hypothesis is proposed to explain the anomalous pattern by which chloride has been found in water of the Upper Floridan aquifer in Brunswick, Glynn County, Georgia. Analyses of geophysical, hydraulic, water chemistry, and aquifer test data using the equivalent porous medium (EPM) approach are used to support...

Two flooding experiments were conducted at two sites with different soils to study the transport and fate of the commonly used herbicide atrazine and inorganic chemicals in the Great Bend Prairie croplands of south-central Kansas. The instantaneous profile method supplemented by the use of an organic (atrazine) and an inorganic...

222Rn was used in the karst drainage basin of the Rio Grande de Manati in Puerto Rico to study groundwater/surface flow relationships. Locations of groundwater influx along two sections of the Rio Grande de Manati were identified. The 222Rn measurements were used together with stream discharge data in a mass balance...

In present acidification models, soilwater characteristics, though modelled, are seldom checked against field observations. Given that such data are now collected as part of many catchment studies, a technique is developed whereby stream water can be predicted as a mixture of the observed soilwater classes or end-members. Provided that a...

After the 17 October 1989 Loma Prieta, central California, earthquake (291 00:04:15.25 UTC, Ms=7.1), the U. S. Geological Survey recorded aftershocks at sites of seismologic and engineering interest. This report describes a seismic-waveform dataset collected from 17 October 1989 (291 UTC) to 14 March 1990 (073 UTC) with GEOS digital...

This map of the Richfield 1° x 2° quadrangle, Utah, shows the regional distribution of cadmium and antimony in the nonmagnetic fraction of drainage-sediment samples. It is part of a folio of maps of the Richfield 1° x 2° quadrangle, Utah, prepared under the Conterminuous United States Mineral Assessment Program....