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Charles E. Sloan

Publications and source records attributed to Charles E. Sloan.

8 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↗
USGS1979

Reconnaissance snow surveys of the National Petroleum Reserve in Alaska, April 1977 and April-May 1978

Reconnaissance snow surveys of the NPRA (National Petroleum Reserve in Alaska) were made in April 1977 and April-May 1978 to ascertain general snow characteristics and distribution patterns. Thirty-nine sites in 1977 and forty-one sites in 1978 were sampled to determine snow depth, density, structure, and snow-soil interface temperature. In addition, snow surface wind indicators were examined over most of NPRA. In April and early May of two consecutive years, the snow cover in NPRA was thin, wind-packed, and virtually continuous. The depth and water equivalent of the snow generally increased with altitude and with distance from the coastal plain. Snow depth on tundra ranged from less than 0.20 m (meters) near the coast to more than 0.90 m in parts of the Brooks Range. Snow density was relatively high in areas where wind slab was developed throughout the snowpack, and lower where there was less wind slab. In 1977, the coastal plain showed the greatest wind slab development and higher densities, averaging 310 kg/cu m (kilograms per cubic meter) on tundra, while the mountains and foothills had less wind slab and lower densities, averaging 270 kg/cu m. In 1978, with more local variation, snow density on the coastal plain averaged 330 kg/cu m on tundra and averaged 310 kg/cu m in the mountains and foothills. Water equivalent of the snowpack in 1977 ranged from less than 0.10 m in the coastal areas to more than 0.25 m in the Brooks Range, and averaged nearly 0.12 m on tundra for the entire area. Water equivalent of the snowpack averaged more than 0.13 m in 1978. Snow-soil interface temperatures in 1977 ranged from about -20C on the coastal plain, where the snowpack was thin and ambient air temperatures were low, to about -5C in the mountains and foothills where the snowpack was thicker and ambient air temperatures higher. (Kosco-USGS)

Open-File Report↗
USGS1972

Water-resources reconnaissance of Anaktuvuk Pass, Alaska

A hydrologic reconnaissance was made of Anaktuvuk pass in the central Brooks Range during the summer of 1971 to help develop a water supply for the village school. Winter icings and summer flow conditions in Contact Creek both indicate that ground water is present beneath the creek bed. A well-site area was selected in the channel of Contact Creek near the school where the prospects of obtaining a suitable ground-water supply seem best. In the event that wells are unsuccessful, water can be hauled from Eleanor Lake to the school. Chemical quality of water at Anaktuvuk Pass is excellent, but any source of water may be subject to bacterial contamination and would require treatment.

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↗
USGS1968

Generalized hydrology of prairie potholes on the Coteau du Missouri, North Dakota

This report presents all the information, obtained during the investigation, that lends itself to generalization. It describes conditions on that part of the Coteau du Missouri where there is little integration of drainage systems. The surface of the glacial drift in this region is dotted with shallow depressions known as prairie potholes that hold water for varying lengths of time. Precipitation directly on a pothole is the basic source of its water supply, but it is only about half the potential evaporation; therefore, potholes tend to go dry. Basin inflow from melting snow or rain occurs only when the soil is frozen or saturated, a condition so erratic in occurrence that seasonal or annual precipitation is of little value as an indication of basin inflow. Net seepage outflow occurs from potholes on the higher parts of the Coteau at very low rates, but it can amount to 20 to 30 percent of the total water loss from a pothole. Net seepage inflow occurs at the potholes on the lower parts of the Coteau. The phreatic surface (water table) tends to be a subdued image of the topography and is generally very near the land surface. The water surfaces of the potholes are part of the phreatic surface, and therefore they can be used to prepare a contour map of the phreatic surface; wells usually act as piezometers and thus are useless for such a purpose. Generally, potholes with water relatively low in dissolved solids have net seepage outflow, and those with water containing high concentration of dissolved solids have net seepage inflow. The direction of ground-water movement can therefore be inferred from the quality of water in potholes. The total salinity of water in a pothole is largely a function of the rate of ground-water flow and the relationship of seepage inflow to outflow. The species of emergent aquatic vegetation that grow in a pothole are directly related to the permanence and salinity of the water at the particular site of each species. The report contains a table of the common species that can be used as indicators of these conditions.

Circular↗