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Digital data sets that describe aquifer characteristics of the Antlers aquifer in southeastern Oklahoma
This data set consists of digitized polygons of constant recharge values 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 recharge polygons were developed from recharge rates 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 recharge rates used as input to the ground-water flow model were 0.32 inches per year for the western portion of the aquifer and 0.96 inches per year for the eastern portion of the aquifer. 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.