Geology topics

Wayne A. Van Voast

Publications and source records attributed to Wayne A. Van Voast.

4 recordsLinked to original sources

USGS2010

Ground-water flow related to streamflow and water quality

A ground-water flow system in southwestern Minnesota illustrates water movement between geologic units and between the land surface and the subsurface. The flow patterns indicate numerous zones of ground-water recharge and discharge controlled by topography, varying thicknesses of geologic units, variation in permeabilities, and the configuration of the basement rock surface. Variations in streamflow along a reach of the Yellow Medicine River agree with the subsurface flow system. Increases and decreases in runoff per square mile correspond, apparently, to ground-water discharge and recharge zones. Ground-water quality variations between calcium sulfate waters typical of the Quaternary drift and sodium chloride waters typical of the Cretaceous rocks are caused by mixing of the two water types. The zones of mixing are in agreement with ground-water flow patterns along the hydrologic section.

Water Resources Research↗

USGS1972

Water resources of the Minnesota River-Hawk Creek watershed, southwestern Minnesota

The Minnesota River – Hawk Creek watershed is located in southwestern Minnesota. The watershed has an area of 1,479 square miles and is drained along its southwestern edge by the Minnesota River (Minnesota Division of Waters, 1959). The major watercourse within the watershed is Hawk Creek, having a drainage area of 510 square miles. Other, shorter streams drain into the Minnesota River but are mostly ephemeral. The watershed has a gently undulating land surface formed on glacial deposits. Directly underlying the glacial deposits in most of the area are Cretaceous sedimentary rocks. Paleozoic and Precambrian rocks are also locally in contact with overlying glacial deposits. Beds of sand and gravel buried at various depths within the glacial deposits are generally thin and discomtinuous but are the most accessible and widely used aquifers in the watershed. Beds of poorly consolidated sandstone in the Cretaceous rocks are locally good aquifers, generally yielding softer water, but in lesser quantities, than aquifers in the overlying glacial deposits. In the eastern part of the watershed, aquifers in Paleozoic and Precambrian sedimentary rocks are capable of high yields to wells and contain water of similar quality to water in the overlying Cretaceous and glacial deposits.

Minnesota↗

USGS1971

Ground water for irrigation in the Brooten-Belgrade area, west-central Minnesota

Water for irrigation is needed to improve crop yields from sandy soils in the Brooten-Belgrade area. Ground-water supplies of sufficient quantity and suitable quality for irrigation are available in much of the area. Quaternary glacial drift, as much as 300 feet thick, is underlain by Precambrian crystalline rocks and possibly by Cretaceous sedimentary rocks. Sand and gravel aquifers are buried at various depths in the drift and can be located by test drilling. One buried aquifer, possibly capable of high yields, is within 250 feet of the land surface in the vicinity of Belgrade. Glacial outwash comprises the upper part of the drift in most of the project area and is locally more than 100 feet thick. The outwash is made up of crossbedded sand and gravel that is interbedded in places with silt and clay deposits and has a saturated thickness of as much as 65 feet. Locally, the transmissivity of the surficial aquifer is as much as 60,000 gallons per day per foot, but elsewhere is generally less than 30,000 gallons per day per foot. The aquifer should yield more than 300 gallons per minute and locally more than 1,000 gallons per minute to individual wells in much of the northern and southwestern parts of the area. Recharge to the surficial aquifer is almost entirely from precipitation. Significant ground-water losses occur as base flow and underflow, and through evaporation and transpiration. Water in the buried and surficial aquifers is of the calcium magnesium bicarbonate type and is of suitable quality for irrigation. An analog model, simulating yearly 30-day pumping periods and hypothetical volumes and distributions of withdrawals, showed the effects on the surficial aquifer of withdrawals of about 20,000 acre-feet per pumping season for 20 years. Predicted water-level declines caused by withdrawals of 20,000 acre-feet per pumping season were generally less than 5 feet in the surficial aquifer and years Predicted water-level declines caused by withdrawals of 20,000 acre-feet pumping season caused predicted water-table declines of more than 10 feet in large parts of the area and caused lake-level declines of as much as 8 feet. The model indicated that water removed from aquifer and lake storage accounted for less than 50 percent of all withdrawals; the remainder was accounted for by water recovered from stream base flow and by water diverted from evaporation and transpiration.

Minnesota↗

USGS1971

Ground water for irrigation near Lake Emily, Pope County, west-central Minnesota

In the Lake Emily area, thickness of the glacial drift ranges from about 200 feet to more than 400 feet. Within the drift are sand and gravel aquifers, some of which can yield adequate water supplies for irrigation. Outwash, as much as 60 feet thick, lies at the surface. The outwash has saturated thicknesses of more than 40 feet and transmissivities of more than 50,000 gallons per day per foot locally in the northern and western parts of the area. In the places of large saturated thickness and high hydraulic conductivity, the aquifer should yield more than 600 gallons per minute to wells. Theoretical maximum yields to wells in most of the area are more than 100 gallons per minute. Chemically, water in the buried and surficial aquifers is mainly of a calcium magnesium bicarbonate type and is suitable for irrigation. Calculated and estimated sodium adsorption ratios and salinity and boron concentrations are below the limits recommended by the U.S. Department of Agriculture.

Minnesota↗