This data set consists of digital polygons of constant hydraulic conductivity values for the alluvial and terrace deposits along the Cimarron River from Freedom to Guthrie in northwestern Oklahoma. Ground water in 1,305 square miles of Quaternary-age alluvial and terrace deposits along the the Cimarron River from Freedom to Guthrie is an important source of water for irrigation, industrial, municipal, stock, and domestic supplies. Alluvial and terrace deposits are composed of interfingering lenses of clay, sandy clay, and cross-bedded poorly sorted sand and gravel. The aquifer is composed of hydraulically connected alluvial and terrace deposits that unconformably overlie the Permian-age Formations.

The hydraulic-conductivity values for alluvial and terrace deposits used in this data set were published in a steady-state ground-water flow modeling report. The aquifer boundaries along geological contacts were extracted from published digital geology data sets. Boundaries defining the geographic limits of the aquifer were digitized from a mylar map, at a scale of 1:250,000. The maps were published at a scale of 1:900,000. The hydraulic conductivity values are 104.5 feet per day for the alluvial deposits and 47.5 feet per day for the terrace deposits.

Ground-water flow models are numerical representations that simplify and aggregate natural systems. Models are not unique; different combinations of aquifer characteristics may produce similar results. Therefore, values of hydraulic conductivity used in the model and presented in this data set are not precise, but are within a reasonable range when compared to independently collected data.