The Ohio Geological Survey's Longyear Hydro-44 drill core rig operating on the site of an American Aggregate Corporation quarry lease near the town of Lytle, Warren County, Ohio. The Warren County Deep Core Hole project was the second continuously cored hole planned to be drilled into the Precambrian basement rock in Ohio. The Ohio Geological Survey expected to reach the Precambrian rock at a depth of about 3,400 feet. At that depth, the drill rig shown working here encountered a previously unknown massive sandstone formation underlying the Mount Simon Sandstone of Upper Cambrian rock. The core hole went 1,910 feet into this sandstone. This core DGS # 2627 went to a total depth of 5,380 feet at the drill site without reaching Precambrian [...]