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Charles E. Sloan

Publications and source records attributed to Charles E. Sloan.

4 recordsLinked to original sources
USGS1980

Reconnaissance snow survey of the National Petroleum Reserve in Alaska, April-May 1979

Moderately low snowfall and an early and abrupt spring thaw resulted in removal of most of the snow cover from the National Petroleum Reserve in Alaska (NPRA) before the snow survey of April 30 through May 2, 1979. Logistical problems and lack of snow permitted sampling at only seven sites. The average snow depth (0.263 meter) was approximately 60% of that measured in the 1977 and 1978 surveys. Snow density in 1979 averaged 337 kilograms per cubic meter and water equivalent averaged 0.088 meter. These two values are about 110% and 70%, respectively, of values for those characteristics in 1977-78. The average temperature of -5.2 Celsius at the base of the snowpack was about 6 Celsius higher than in the previous surveys. Extensive recent slab avalanche activity was noted in the Brooks Range. (USGS)

Alaska↗
USGS1972

Some effects of a heated pipeline on ground-water flow in Alaska

The thaw bulb produced by a heated pipeline buried in a stream channel may intercept water confined in shallow unfrozen zones beneath a seasonally frozen layer. Resulting movement of ground water through the thaw bulb might produce quick conditions in the pipeline foundation materials. A digital model showed that such conditions are not likely to occur. Test drilling along the proposed route of the pipeline confirms this conclusion. An exception may be the situation in which the pipeline is buried in fine sand overlying a highly permeable coarse sand or gravel. The results of model studies demonstrate that the heated trench will focus ground-water discharge near the pipeline, especially in winter. Such discharge will increase the number and size of icings. Explosive icing mounds apparently result from high crystallization pressures that develop within a closed talik. The thaw bulb close to the buried pipeline relieves the pressure that leads to such conditions. Potential problems related to thaw-bulb enlargement by heat convection and thaw-instability of fine-grained materials are not treated in this analysis.

Alaska↗