| Summary: | Includes bibliographical references (pages [48]-52) Electrical resistivity measurements obtained in Wright and Taylor Valleys, Antarctica, indicate the presence of unfrozen zones extending through the regional permafrost at several locations: l) Lake Vanda, Wright Valley; 2) Lake Bonney, Taylor Valley; 3) two small basins in western Wright Valley; 4) along the Ross Sea in eastern Taylor Valley; 5) and at the Taylor Glacier red discharge. Other areas in the valleys are generally underlain by at least several meters of frozen ground. The presence of unfrozen zones in this area provides a hydrologic connection between surface and subsurface waters. Discharge of groundwater at any of these sites would allow accumulation of subsurface-derived minerals. The saline discharge at the terminus of Taylor Glacier is suggestive of a site where mineralized waters, moving laterally beneath the continental ice sheet, are discharged. A small saline pond in western Wright Valley was found to contain an abundant copper compound (approximately 1000 ppm by weight), indicating the possible existence of copper ore in this region. Several causes for the existence of unfrozen zones in a region with an average annual temperature of -18°C are possible. These include: 1) outlet glacier fluctuations; 2) heat associated with recent tectonic activity; 3) a lowered freezing point due to high salt concentrations; 4) the addition of heat transported by groundwater; 35) and the presence of major lakes which store heat. A combination of these causes result in a modified permafrost zone. M.S. (Master of Science)
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