The drilling history documents oil and gas wells in the Middle Miocene sequence as a whole and in 10-year intervals. The wells included in this interval are determined by completion date and by comparing the depth of the wells to structure contours of the Middle Miocene sequence. The data are provided in a single file (mm_prod.shp) as well as eight 10-year interval files covering 1920 through 1999. These datasets contain basic data and interpretations developed and compiled by the U.S. Geological Survey's Framework Studies and Assessment of the Gulf Coast Project. Other major sources of data include publicly available information from state agencies as well as publications of the U.S. Geological Survey and other scientific organizations. In cases where company proprietary data were used to produce various derivatives such as contour surfaces, the source is cited but the data are not displayed.