Digital hydraulic conductivity values of the Antlers aquifer in southeastern Oklahoma

This data set was created for a project to develop data sets to support
ground-water vulnerability analysis. The objective was to create and document a
digital geospatial data set from a published report or map, or existing digital
geospatial data set that could be used in ground-water vulnerability analysis.

This data set consists of digitized polygons of a constant hydraulic
conductivity value for the Antlers aquifer in southeastern Oklahoma. The Early
Cretaceous-age Antlers Sandstone is an important source of water in an area
that underlies about 4,400-square miles of all or part of Atoka, Bryan, Carter,
Choctaw, Johnston, Love, Marshall, McCurtain, and Pushmataha Counties. The
Antlers aquifer consists of sand, clay, conglomerate, and limestone in the
outcrop area. The upper part of the Antlers aquifer consists of beds of sand,
poorly cemented sandstone, sandy shale, silt, and clay. The Antlers aquifer is
unconfined where it outcrops in about an 1,800-square-mile area.

The hydraulic conductivity polygons were developed from the hydraulic
conductivity value used as input into a ground-water flow model and from
published digital data sets of the surficial geology of the Antlers Sandstone
except in areas overlain by alluvial and terrace deposits near streams. Some of
the lines were interpolated where the Antlers aquifer is overlain by alluvial
and terrace deposits. The interpolated lines are very similar to the aquifer
boundaries shown on maps published in a ground-water modeling report for the
Antlers aquifer. The constant hydraulic conductivity value used as input to the
ground-water flow model was estimated as 5.74 feet per day.

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.