Digital data sets that describe aquifer characteristics of the Enid isolated terrace aquifer in northwestern Oklahoma

This data set consists of a digitized polygon of a constant
recharge value for the Enid isolated terrace aquifer in
northwestern Oklahoma. The Enid isolated terrace aquifer covers
approximately 82 square miles and supplies water for irrigation,
domestic, municipal, and industrial use for the City of Enid and
western Garfield County. The Quaternary-age Enid isolated
terrace aquifer is composed of terrace deposits that consist of
discontinuous layers of clay, sandy clay, sand, and gravel. The
aquifer is unconfined and is bounded by the underlying
Permian-age Hennessey Group on the east and the Cedar Hills
Sandstone Formation of the Permian-age El Reno Group on the
west. Cedar Hills Sandstone Formation fills a channel beneath
the thickest section of the Enid isolated terrace aquifer in the
midwestern part of the aquifer.

The polygons boundary was digitized from a photocopy of a paper
map from a ground-water modeling thesis and report. The map
digitized was published at a scale of 1:62,500. The recharge
value reported in the ground-water modeling thesis and report
for the Enid isolated terrace aquifer is 2.3 inches per year.

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 recharge 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.