Several types of geologic and hydrologic data were collected and compiled as part of the Central Midwest Regional Aquifer-System Analysis. The study described the hydrology of Cambrian-age through Cretaceous-age rocks in all of Kansas and Nebraska and parts of eight other states. Information from both water wells and petroleum wells was obtained from numerous State, Federal, and private sources. The completeness, quality, and distribution of the data varies considerably. Most data files contain data selected to represent the regional scope of the study. The log data file contains about 850 lithologic logs and about 750 geophysical logs. The hydraulic-head data file contains about 1 ,400 measured water levels and about 2,600 values of equivalent freshwater head derived from drill-stem-test analyses. The hydrochemical data file contains about 2,900 water quality analyses. The aquifer-property data file contains about 1,050 values. In addition to site-specific data, areal information in the form of model-data arrays is available for initial hydraulic head, transmissivity, and vertical leakance. These data describe the major geohydrologic units studied in terms of a three-dimensional grid, 28 rows x 33 columns x 5 layers. Parts of the hydraulic-head, hydrochemical, and aquifer-property data files are proprietary. The fluid-withdrawal data file was developed for study use only. Most other data described herein are available on magnetic tape from the U.S. Geological Survey in Lawrence, Kansas. (USGS)
