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Melvin H. Podwysocki

Publications and source records attributed to Melvin H. Podwysocki.

5 recordsLinked to original sources
USGS2005

Fracture trace map and single-well aquifer test results in a carbonate aquifer in Berkeley County, West Virginia

These data contain information on the results of single-well aquifer tests, lineament analysis, and a bedrock geologic map compilation for the low-lying carbonate and shale areas of eastern Berkeley County, West Virginia. Efforts have been initiated by management agencies of Berkeley County in cooperation with the U.S. Geological Survey to further the understanding of the spatial distribution of fractures in the carbonate regions and their correlation with aquifer properties. This report presents transmissivity values from about 200 single-well aquifer tests and a map of fracture-traces determined from aerial photos and field investigations. Transmissivity values were compared to geologic factors possibly affecting its magnitude.

Open-File Report↗
USGS1984

EVALUATION OF LOW-SUN ILLUMINATED LANDSAT-4 THEMATIC MAPPER DATA FOR MAPPING HYDROTHERMALLY ALTERED ROCKS IN SOUTHERN NEVADA.

Landsat-4 Thematic Mapper (TM) data of southern Nevada collected under conditions of low-angle solar illumination were digitally processed to identify hydroxyl-bearing minerals commonly associated with hydrothermal alteration in volcanic terrains. Digital masking procedures were used to exclude shadow areas and vegetation and thus to produce a CRC image suitable for testing the new TM bands as a means to map hydrothermally altered rocks. Field examination of a masked CRC image revealed that several different types of altered rocks displayed hues associated with spectral characteristics common to hydroxyl-bearing minerals. Several types of unaltered rocks also displayed similar hues.

Conference Paper↗
USGS1980

Digital mapping of limonitic rocks by using Landsat MSS radio data

Color-ratio composite images of Landsat MSS (multi-spectral scanner) bands have been used by other workers to map the distribution of limonitic rocks in semi-arid and arid areas as possible indicators of hydrothermal alteration (Rowan et al, 1974). The images are particularly useful for broad overviews, but detailed analysis at large scales requires both numerical analysis of the ratio values to distinguish consistently among categories of limonitic rocks and a precise transfer of the data to large-scale base maps. Both requirements can be met by digital classification followed by a precise geometric registration of the classified data.

Sixth Annual Pecora Symposium and Exposition↗