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Portions of the Savannah River floodplain swamp were evaluated for vegetation change using high resolution (5a??6 m) aircraft multispectral scanner (MSS) data. Image distortion from aircraft movement prevented precise image-to-image registration in some areas. However, when small scenes were used (200-250 ha), a first-order linear transformation provided registration accuracies of...

Typical geodetic measurements of deformation consist of repeated surveys of a particular geodetic network. Such deformation data can be interpreted as a consequence of one or more self-coherent sources by means of principal component analysis. A self-coherent source is defined as any source that produces deformation that is time and...

Garnet, an uncommon accessory mineral in igneous rocks, occurs in seven small peraluminous granitoid plutons in the southeastern Arabian Shield; textural equilibrium between garnet and other host granitoid minerals indicates that the garnets crystallized from their host magmas. Compositions of the garnets form three groups that reflect host-granitoid compositions, which...

The hydraulic potentiomanometer described herein consists of a potentiometer connected to a manometer by a flexible tube. The device is used to directly measure the direction of seepage as well as the hydraulic-head difference between groundwater and surface water. The device works most effectively in sandy materials. For accurate measurements...

The Florida reefs have evolved over the last 7000 years during rising sea level. An ancient reef existed from sand shoals on which Miami and Key West are now sited before the last glaciation (100 000 to 125 000 years ago). During the glacial period sea level fell to >300...

Dilatational earth strain, associated with the radiation fields for several hundred local, regional, and teleseismic earthquakes, has been recorded over an extended bandwidth and dynamic range at four borehole sites near the San Andreas fault, CA. The general theory of linear viscoelasticity is applied to account for anelasticity of the...

Hydrologic modeling of stream-aquifer interaction commonly has been used to quantify transit losses associated with water deliveries, such as those from reservoir storage. This technique requires estimation of model parameters that include stage-discharge relations, channel-storage coefficient, aquifer transmissivity, and aquifer-storage coefficient. Because data to reliably estimate or calibrate these parameters...

We have inverted the teleseismic P waveforms recorded by stations of the Global Digital Seismograph Network for the 8 July 1986 North Palm Springs, California, the 28 October 1983 Borah Peak, Idaho, and the 19 September 1985 Michoacan, Mexico, earthquakes to recover the distribution of slip on each of the...

No abstract available....

This study evaluates the differences in the visible and near-IR responses of the Advanced Very High Resolution Radiometers (AVHRR) of the National Oceanic and Atmospheric Administration (NOAA)-9 and -10 satellites for coincident sample locations. The study also evaluates the differences in vegetation indices computed from those data. Data were acquired...

Estimates of the depth to the Curie temperature isotherm in Nevada are in accordance with other regional geologic and geophysical information and together can be explained in the context of present-day tectonism. A method to estimate the depth extent of magnetic sources from the statistical properties of magnetic anomalies was...

The system design is premised on a proven, areal two-dimensional, finite-difference flow/transport model which is supported by an operational set of computer programs for input data management and model output interpretation. The purposes of the project are (1) to demonstrate the utility of the model for providing useful highway design...

A series of decomposed and coalified gymnosperm woods was examined by conventional solid-state 13C nuclear magnetic resonance (NMR) and by dipolar-dephasing NMR techniques. The results of these NMR studies for a histologically related series of samples provide clues as to the nature of codification reactions that lead to the defunctionalization...

No abstract available....

Near-infrared (NIR) reflectance spectra for mixtures of ordered kaolinite and ordered dickite have been found to simulate the spectral response of disordered kaolinite. The amount of octahedral vacancy disorder in nine disordered kaolinite samples was estimated by comparing the sample spectra to the spectra of reference mixtures. The resulting estimates...

No abstract available....

This month we demonstrate an example of the use of thermal infrared imagery to produce a relatively sharp surrogate shaded-relief image. The image shows one aspect of the drama and usefulness of calibrated thermal imagery that (because of compatible projection and pixel size) can be easily combined with other spectral...

A 48-mGal gravity low coincides with Long Valley caldera and is mainly attributed to low-density caldera fill. Gravity measurements by Unocal Geothermal have been integrated with U.S. Geological Survey data, vastly improving gravity station coverage throughout the caldera. A strong regional gravity trend is mainly attributed to isostasy. A “best...

Depositional controls on peat-forming environments which produce thick (>10m) coal beds can be inferred from relationships between coal bed geometry, maceral composition and associated lithologies. Study of these relationships within sedimentary sequences associated with the Wyodak-Anderson (Palaeocene) and the Felix (Eocene) sub-bituminous coal beds in the Powder River Basin,...

A U.S. Geological Survey investigation was conducted, in cooperation with the Virginia Water Control Board, to analyze the hydrogeology and groundwater flow system in the Coastal Plain physiographic province of southeastern Virginia, and to assess the continued reliability of groundwater as a freshwater resource. To provide a more detailed analysis...

We report results from a paleomagnetic study of the Yukon-Koyukuk province, a key region for reconstructing the Cretaceous paleogeography of northern Alaska and northeastern Asia. The province lies between the displaced continental fragment of Arctic Alaska and the accreted terranes of southern Alaska. Although Lower Cretaceous volcanogenic rocks of the...

No abstract available....

Factors controlling the concentration of dissolved hydrogen gas in anaerobic sedimentary environments were investigated. Results, presented here or previously, demonstrated that, in sediments, only microorganisms catalyze the oxidation of H2 coupled to the reduction of nitrate, Mn(IV), Fe(III), sulfate, or carbon dioxide. Theoretical considerations suggested that, at steady-state conditions, H2...

A revision of the Birkenes model of streamwater acidification has been attempted to incorporate additional chemical and hydrologic information gained in the last 6 years since its original construction. The first stage of this effort has been an analysis of the hydrologic submodel with the goal of extending it to...

Waterfowl, fish, invertebrates, and plants were collected from impoundments used for evaporating subsurface irrigation drainwater in Kings and Kern counties, California. Specimens were analyzed for trace elements with emphasis on selenium. Dry weight concentrations of total selenium ranged from 2.5 to 17 μg/g in wigeongrass, Ruppia maritima; 7.6 to 30...