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Philip A. Emery

Publications and source records attributed to Philip A. Emery.

8 recordsLinked to original sources
USGS1971

Resistivity sections, upper Arkansas River basin, Colorado

A reconnaissance investigation of ground-water resources in the upper Arkansas River basin from Pueblo to Leadville is being made by the U.S. Geological Survey in cooperation with the Southeastern Colorado Water Conservancy District, and the Colorado Division of Water Resources, Colorado State Engineer. As part of the investigation, surface geophysical electrical resistivity surveys were made during the summer and fall of 1970 near Buena Vista and Westcliffe, Colo. (p1.1). The resistivity surveys were made to verify a previous gravity survey and to help locate areas where ground-water supplies might be developed. This report presents the results of the surveys in the form of two resistivity sections.

Colorado↗
USGS1967

Availability of ground water in York County, Nebraska

York County, an area of 575 square miles, is situated on an upland plain in southeast Nebraska. Although tributaries of the Big Blue River have eroded valleys into this plain, much of the original surface is still intact and is characterized by broad shallow undrained depressions. The economy is based almost wholly on agriculture, and corn is the major crop. More than 111,000 acres of cropland was irrigated in 1964 with water pumped from 1,240 wells. The upland plain is underlain to depths of 100-450 feet by unconsolidated deposits of Quaternary age. The upper part of this depositional sequence consists largely of wind-deposited clayey silt, and the lower part consists of stream-deposited sand and gravel. In part of the county, the sequence includes some glacial till also. The unconsolidated Quaternary deposits mantle the eroded surface of marine strata of Cretaceous age. The lower unconsolidated rocks of Quaternary age are saturated and constitute a highly productive aquifer throughout much of the county. Replenishment to this aquifer, derived principally from precipitation, is believed to average about 1.5 inches per year. As the quantity of ground water pumped per year greatly exceeds the average annual quantity of recharge, most of the. water used for irrigation is from storage. Consequently, water levels have been trending downward. A comparison of 1964 water levels in wells with water levels measured in 1953 shows that the water table declined more than 10 feet beneath 42 square miles. The ground water is of the calcium bicarbonate type, and, though hard, is chemically suitable for irrigation use on most soils in the county.

Nebraska↗
USGS1964

Geology and ground-water resources of Richardson County, Nebraska

Richardson County is in the extreme southeast corner of Nebraska. It has an area of 545 square miles, and in 1960 it had a population of 13,903. The county is in the physiographic region referred to as the Dissected Loess-covered Till Prairies. Major drainage consists of the Big Nemaha River, including its North and South Forks, and Muddy Creek. These streams flow southeastward and empty into the Missouri River, which forms the eastern boundary of the county. The climate of Richardson County is subhumid; the normal annual precipitation is about 35 inches. Agriculture is the chief industry, and corn is the principal crop. Pleistocene glacial drift, loess, and alluvial deposits mantle the bedrock except in the southern and southwestern parts of the county where the bedrock is at the surface. Ground water is obtained from glacial till, fluvioglacial material, terrace deposits, and coarse alluvial deposits, all of Pleistocene age--and some is obtained from bedrock aquifers of Pennsylvanian and Permian age. Adequate supplies of ground water are in many places difficult to locate because the water-bearing sands and gravels of Pleistocene age vary in composition and lack lateral persistence. Perched water tables are common in the upland areas and provide limited amounts of water to many of the shallow wells, Very few wells in bedrock yield adequate supplies, as the permeability of the rock is low and water that is more than a few tens of feet below the bedrock surface is highly mineralized. Recharge is primarily from local precipitation, and water levels in many wells respond rapidly to increased or decreased precipitation. The quality of the ground water is generally satisfactory for most uses, although all the water is hard, and iron and manganese concentrations, in some areas, are relatively high. Ground water is used mainly for domestic and stock purposes.

Water Supply Paper↗