Petroleum industry in Illinois, 1966--oil and gas developments and waterflood operations

Illinois produced 61,982,000 bbl of crude oil in 1966, down 2.7% from 1965. Approximately 43,451,000 bbl, or 70%, of this production was from secondary recovery waterflood projects. The price of Illinois crude oil at the wells in 1966 was based on a gravity scale. In 1966, 1,260 new tests for oil and gas were drilled. They resulted in 674 oil wells, 3 gas wells, and 583 dry holes. In addition, 100 former dry holes were re-entered and completed as producers, 99 as oil wells and 1 as a gas well; 24 former producers were recompleted as oil wells in new pay zones. There were 319 new service wells drilled, and 371 oil wells were converted to service wells. Estimated crude oil reserves declined from 363.4 million bbl at the end of 1965 to 344.4 million bbl at the end of 1966. Twenty-two underground natural gas storage projects are in operation or being developed in Illinois. Sixty-nine new waterflood projects were added during 1966. These additions were offset by 50 abandonments and 29 projects dropped either for lack of data or because the information was combined with that of another project covering the same area.