ARC/INFO export and nonproprietary format files This diskette contains digitized aquifer boundaries and maps of of hydraulic conductivity, recharge, and ground-water level elevation contours for the alluvial and terrace deposits along the alluvial and terrace deposits along the North Canadian River from Canton Lake to Lake Overholser in central Oklahoma. Ground water in approximately 400 square miles of Quaternary-age alluvial and terrace aquifer is an important source of water for irrigation, industrial, municipal, stock, and domestic supplies. The aquifer consists of clay, silt, sand, and gravel. Sand-sized sediments dominate the poorly sorted, fine to coarse, unconsolidated quartz grains in the aquifer. The hydraulically connected alluvial and terrace deposits unconformably overlie Permian-age formations. The aquifer is overlain by a layer of wind-blown sand in parts of the area. Most of the lines in the aquifer boundary, hydraulic conductivity, and recharge data sets were extracted from published digital surficial geology data sets based on a scale of 1:250,000. The ground-water elevation contours and some of the lines for the aquifer boundary, hydraulic conductivity, and recharge data sets were digitized from a ground-water modeling report about the aquifer published at a scale of 1:250,000. The hydraulic conductivity values and recharge rates also are from the ground-water modeling report. 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 and 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.