A computerized data base of geologic logs for selected deep wells in parts of Oklahoma, Texas, and New Mexico was prepared by the U.S. Geological Survey as part of the Central Midwest Regional Aquifer-System Analysis. At least one well per county in the study area was selected, and the geologic logs for the wells were entered into the data base. Summaries of the geologic logs are presented in this report. Geophysical logs were used for interpretation of the geologic logs, and a list of these geophysical logs also is presented. These geophysical logs are available for inspection at the U.S. Geological Survey office in Oklahoma City, Oklahoma.