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A general computer code, developed to calculate anelastic reflection-refraction coefficients, energy flow, and the physical characteristics for general P, S-I, and S-II waves, quantitatively describes physical characteristics for wave fields in anelastic media that do not exist in elastic media. Consideration of wave fields incident on boundaries between anelastic media shows that scattered...

Measurements of dilational earth strain in the frequency band 25–10−5 Hz have been made on a deep borehole strainmeter installed near the San Andreas fault. These data are used to determine seismic radiation fields during nuclear explosions, teleseisms, local earthquakes, and ground noise during seismically quiet times. Strains of less than...

A simple different equation model was developed to provide additional perspective on observed mortality and trend data on Yellowstone grizzly bears (Ursus arctos horribilis). Records of mortalities of adult females from 1959 to 1985 were utilized, in conjunction with data on females with cubs. The overall downward trend...

The Instream Flow Incremental Methodology (IFIM) is a habitat-based tool used to evaluate the environmental consequences of various water and land use practices. As such, knowledge about the conditions that provide favorable habitat for a species, and those that do not, is necessary for successful implementation of the methodology. In...

The tensiometer, introduced by Richards and Gardner (1936) has been a tool often ignored in unsaturated zone investigations. Hazardous waste disposal studies that require values of unsaturated zone matric potentials will expand tensiometer use. Familiarity with operation and installation principles is necessary to ensure quality data collection.The essential elements of...

he neutron borehole logging tool was calibrated for the determination of moisture content in theunsaturated zone of an alluvial aquifer. A continuous core sample was collected to a depth of 15 ft from the unsaturated zone.Moisture content and other soil properties were determined by standard soil-laboratory techniques. The neutron logs profile was correlated...

Water has become a critical commodity in the Caribbean Region. In spite of a relative abundance of rainfall even on the smaller islands, the region is faced with severe seasonal shortages as well as increasing water quality problems. The supply of thewater needs in the area will become even more critical...

The sequence of glacial deposits near McCall, Idaho, previously assigned to the Pinedale and Bull Lake glaciations, contains deposits of four different ages. These ages are defined by multiple relative-age criteria, including weathering rinds, soil development, surface-rock weathering, morainal morphology, and loess stratigraphy. The thickness of weathering rinds on basaltic...

The author presents a numerical method for calculating the density and S-wave velocity in the upper mantle of a spherically symmetric, non-rotating Earth which consists of a perfect elastic, isotropic material. The data comes from the periods of the toroidal oscillations. She tests the method...

Several species of vertebrates may find optimal habitat for breeding, nesting, or foraging in old-growth (>200 years old) confierous forests in the Pacific Northwest. Old-growth forests are economically valuable, however, and most unprotected stands will be cut within 40 years (Franklin et al., 1981). Meslow et al. (1981)...

Numerous surveys have shown that fish species richness (number of species) is positively correlated with lake pH. However, species richness of fish communities is also correlated with lake size, and low‐pH lakes are often small. Thus, conclusions drawn from examination of fish community structure relative to spatial...

An instrument system has been constructed that can monitor and sample suspended sediment distributions in the benthic boundary layer. It consists of miniature nephelometers and suspended sediment samplers placed within one meter of the seabed. The system is capable of continuously monitoring suspended sediment profiles at eight levels between 14...

Improved methods of calculating bed material stability and transport must be developed for a gravel bed stream having an armoured surface in order to use the HEC-6 model to examine channel change. Good possibilities exist for use of a two layer model based on the Schoklitsch and the Einstein-Brown...

Hydrogeologic studies commonly include the development, calibration, and application of a deterministic simulation model. To help assess the value of using such models to make predictions, a postaudit was conducted on a previously studied area in the Salt River and lower Santa Cruz River basins in central Arizona. A deterministic,...

Selected studies from the literature were reviewed to determine the extent of knowledge about the relationship between hydrology and wetland ecosystem studies. Wetland studies of chemical input-output relationships have been the most dependent on hydrologic data of all wetland investigations; yet, very few of these studies have attempted to measure...

A study was performed to identify sources of solute loading to the Dirty Devil River and its major tributaries, in southeastern Utah. A primary goal was to determine the contribution of gypsum dissolution to total dissolved solids concentration, and its potential increase in the future if salinity...

Oil and gas exploration and engineering studies in water‐covered areas routinely use continuous seismic profiling techniques to obtain subsurface geologic information. Such profiling also can be used effectively in hydrologic studies to define the geologic framework of aquifer systems, to locate hydrologic boundaries, and in some places, to interpret the...

During 1983-84, ground water from 63 wells located at 31 sites throughout, eastern Broward County, Florida, was sampled and analyzed to determine baseline water-quality conditions. The physical and chemical parameters analyzed included field measurements (pH and temperature), physical characteristics (color, turbidity, and specific conductance), major inorganic ions, nutrients (nitrogen, phosphorus,...

Landsat multispectral images of the Antarctic ice sheet have been digitally enhanced by the US Geological Survey to show ice surface features not seen in earlier photographic products of the same scenes. Now for the first time it is worthwhile to prepare image maps at scales of up to 1:250...

A 5-year double-bind test was conducted to test the predictive capability of a previously published (Picton 1978) regression (Y= 2.01 + 0.042x), which described the relationship between the littler size of grizzly bears (Ursus arctos horribilis) and an index of climate plus carrion availability (climate-carrion index). This regression showed...

No abstract available....

Grizzly bear habitat research began in 1967 and is continuing in Glacier National Park, MT. Direct observations and fecal analysis revealed a relatively definable pattern of habitat use by the bears. Habitat data were subsequently used to develop management models and explore the relationships between grizzlies and park...

Using several isotopic techniques, we have determined the ages of selected metamorphic rocks in the Yukon-Tanana terrane (YTT) of east-central Alaska. U-Pb zircon data from an augen gneiss body in the Big Delta quadrangle indicate that the granitoid protolith of the gneiss was intruded 341 ± 3 m.y. ago (lower...

No abstract available....

No abstract available....