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William W. Dudley

Publications and source records attributed to William W. Dudley.

3 recordsLinked to original sources

Multidisciplinary hydrologic investigations at Yucca Mountain, Nevada

Future climatic conditions and tectonic processes have the potential to cause significant changes of the hydrologic system in the southern Great Basin, where a nuclear-waste repository is proposed for construction above the water table at Yucca Mountain, Nevada. Geothermal anomalies in the vicinity of Yucca Mountain probably result from the local and regional transport of heat by ground-water flow. Regionally and locally irregular patterns of hydraulic potential, local marsh and pond deposits, and calcite veins in faults and fractures probably are related principally to climatically imposed hydrologic conditions within the geologic and topographic framework. However, tectonic effects on the hydrologic system have also been proposed as the causes of these features, and existing data limitations preclude a full evaluation of these competing hypotheses. A broad program that integrates many disciplines of earth science is required in order to understand the relation of hydrology to past, present and future climates and tectonism.

Conference Paper↗

Effect of irrigation pumping on desert pupfish habitats in the Ash Meadows, Nye County, Nevada

The Ash Meadows area, at the southern tip of the Amargosa Desert in southern Nevada, discharges ground water collected over several thousand square miles of a regional flow system developed in Paleozoic carbonate rocks. Water moves westward across fault contacts from the bedrock into poorly interconnected gravel, sand, and terrestrial-limestone aquifers in the upper few hundred feet of the basin sediments at Ash Meadows. A small pool in Devils Hole, which is a collapse depression in Cambrian limestone, and numerous springs in the adjacent desert valley contain rare fish species of the genus Cyprinodon, faunal remnants of Pleistocene lakes. The Devils Hole pupfish, C. diabolis, is the most endangered of the several surviving species that have evolved since the post-pluvial isolation of their ancestors. This population feeds and reproduces on a slightly submerged rock ledge. Recent irrigation pumping has nearly exposed this ledge. Correlation of pumping histories with the stage in Devils Hole allows identification of several wells that affect the pool level most severly. Some springs that are habitats for other species of Cyprinodon have reduced discharge because of pumping. Hydraulic testing, long-term water-level monitoring, water quality, and geologic evidence aid in defining the principal flow paths and hydraulic interconnections in the Ash Meadows area. (Woodard-USGS)

Professional Paper↗