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

Abstract

Prepared in cooperation with the Wyoming State Department of Economic Planning and Development. 16. Abstracts ^he 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. Th(area studied is about 800 square miles in southern Niobrara and northern Goshen Counties. Long-term average annual recharge to the aquifer from streams and precipiti tion is estimated to total about 24,270 acre-feet. Pumpage from public-supply and irrigation wells is estimated to have totaled aboi 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 : groundwater 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 groundwater system in the Arikaree Formation. The model can be used to indicate the general effect of applying hydraulic stresses to the system._____________ ____________________________________ 17. Key Words and Document Analysis. I7a. Descriptors Aquifer/ irrigation wells/ groundwater recharge/ transmissivity/ evapotranspiration/ specific yield/ discharge/ potentiometric surface/ seepage. 17b. Identifiers/Open-Ended Terms Digital model/ hydrologic system/ pumpage/ surface-and groundwater relationship 17c. COSATI Field/Group 18. Availability Statement No restriction on distribution.

Geologic and hydrogeologic characteristics of the White River Formation, Lance Formation, and Fox Hills Sandstone, northern greater Denver Basin, southeastern Laramie County, Wyoming

“…Hydrogeologic unit of Lines (1976) and Hoxie (1977Hoxie ( , 1979Hoxie ( , 1983 [Wheatland Flats, Dwyer, and Muleshoe Flat areas, Platte County, Wyo.] Hydrogeologic unit of Crist (1977) [ Hydrogeologic unit of Crist (1980) and Cooley and Crist (1981) [Laramie County, Wyo., and adjacent part of Colo.]…”