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M. A. Crist

Publications and source records attributed to M. A. Crist.

4 recordsLinked to original sources
USGS1989

Procedure for evaluating observation-well networks in Wyoming, and application to northeastern Wyoming, 1986

A sequence of steps was developed for evaluating and modifying the existing, long-term, observation-well network in any part of Wyoming. The State was subdivided geographically into nine groundwater areas, including the northeastern Wyoming groundwater area, based on major structural features. Northeastern Wyoming was the first of the nine areas to be evaluated using these procedures. The stratigraphic units of Wyoming were grouped into five rock units on the basis of age, similar depositional environments, and water-yielding properties. Activities likely to affect groundwater in northeastern Wyoming were evaluated. The most important monitoring needs in the area are related to: (1) Oil-field waterflooding; (2) surface mining of coal; (3) increasing municipal use of groundwater, and (4) need for general resource information. The 18 observation wells in the existing (1986) network meet most of the needs identified. Seven additional wells need to be added to the network, whereas four wells in the network can be discontinued. Water level data from the 18 observation wells are presented by county. Maps and hydrographs are accompanied by brief discussions of information related to the records obtained. (USGS)

Water-Resources Investigations Report↗
USGS1983

Hydrologic conditions in the Wheatland Flats area, Platte County, Wyoming

The area includes about 260 square miles in central Platte County that consists of Wheatland Flats and a border region. Wheatland Flats is an area of about 100 square miles that is bounded by Chugwater Creek on the east, the Laramie River on the north, and Sybille Creek on the west. The southern boundary is approximately the southernmost limit of alluvial terrace deposits. Surface water diverted from the Laramie River along with ground water from wells is used to irrigate about 57,000 acres most of which are on and adjacent to Wheatland Flats. More than 200 wells are used for irrigation, industrial, and municipal supplies. The wells are completed in an upper aquifer consisting primarily of shallow alluvial deposits of Quaternary age and a lower aquifer, the Arikaree Formation of early Miocene age. Net water-level decline after approximately 20 years (1958-60 to 1979) generally is less than 10 feet in each aquifer , although declines of as much as 13 feet have occurred in the Airkaree Formation at specific locations. A digital model was used to simulate hydrologic conditions in the Wheatland Flats area. The model indicated that ground-water discharge to streams decreased by 10 percent from 1971 to 1978. Stream-discharge measurements are not available to verify the loss. However, it is reasonable to assume, on the basis of hydraulic-head decline in the aquifers, that there has been some ground-water contribution to the stream. (USGS)

Water-Resources Investigations Report↗
USGS1977

Hydrologic evaluation of the Arikaree Formation near Lusk, Niobrara and Goshen counties, Wyoming

The Arikaree Formation of early Miocene age is an aquifer of large areal extent and is composed of very fine grained, poorly bedded, loosely to moderately cemented sandstone and interbedded silt, limestone, and many concretionary layers. The area studied is about 800 square miles in southern Niobrara and northern Goshen Counties of Wyoming. Long-term average annual recharge to the aquifer from streams and precipitation is estimated to total about 24,270 acre-feet. Pumpage from public-supply and irrigation wells is estimated to have totaled about 48,000 acre-feet from 1938 through 1972. This pumpage did not cause any noticeable decrease in natural discharge and it is assumed there has been no significant change in ground-water storage. Pumpage is estimated to total about 39,500 acre-feet for the 3-year period 1973 through 1975. A digital model was developed to simulate the ground-water system in the Arikaree Formation. The model can be used to indicate the general effect of applying hydraulic stresses to the aquifer. (Woodard-USGS)

Water-Resources Investigations Report↗