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George A. McCoy

Publications and source records attributed to George A. McCoy.

4 recordsLinked to original sources
USGS1978

Water resources of the Cordova area, Alaska

This report is a compilation of ground-water, surface-water, and water-quality data collected by the U.S. Geological Survey, Water Resources Division on Eyak Lake and Power Creek, near Cordova, and wells in and near Cordova, Alaska. Many of these data were collected as part of a cooperative program with the city of Cordova. The purpose of this report is to present the data in a concise format for interested parties. Cordova is on the southeast shore of Orca Inlet in Prince William Sound (lat 60°33' N.; long 145°45' W.) at an altitude of approximately 90 feet (fig. 7). The limited development has occurred along the north shore of the west arm of Eyak Lake. The current population of Cordova is about 1,800. Commercial fishing and fish processing form the economic base for the community.

Alaska↗
USGS1977

A reconnaissance investigation of a large meromictic lake in southeastern Alaska

Redoubt Lake is one of the largest documented meromictic lakes in North America. The chemocline extends in depth from 80 to 100 m (meters) and the steepest gradient is between 98 and 100 m. The monimolimnion is anoxic, contains hydrogen sulflde, and has a salinity about two-thirds that of seawater. Turnover appears to introduce additional sodium chloride from the chemocline to the mixolimnion, but diffusion is probably the dominant mixing mechanism. Vertical profiles show a dichothermic temperature curve. A minimum temperature of 3°C in the chemocline is unexplained, but higher temperatures in the monimolimnion may be a result of solar radiation. At the lower limit of the chemocline there is a sharp decrease in pH, which could be due to bacterial action. Redoubt Lake is probably a relict fiord. The data presented herein support the hypothesis that the lake was gradually isolated from the sea by uplift. While seawater was entering the lake, it probably mixed with the freshwater in the mixolimnion and therefore the monimolimnion is less saline than seawater. Geologic and geophysical evidence support the speculation that significant amounts of saltwater inflow probably ceased about 650-800 years before the present.

Alaska↗
USGS1976

Limnological investigation of six lakes in southeast Alaska

Limnological data were collected from six lakes in southeast Alaska in 1974. The data include concentrations of major inorganic constituents, nutrients, selected trace metals, total organic carbon, and chlorophyll. Vertical profiles of specific conductance, temperature, dissolved-oxygen saturation, and pH were drawn. With the exception of Redoubt Lake, all of the lakes are very similar chemically. The small differences in chemical composition probably reflect variations in geology of the drainage basins, altitudes, and morphometric characteristics of the lakes. Productivity is so low in all the lakes that it was not possible to rank the lakes by relative productivity from the reconnaissance sampling. Redoubt Lake is meromictic, but the others are probably holomictic and dimictic. (Woodard-USGS)

Alaska↗