Exploration in Pennsylvania during 1963 resulted in the discovery of 3 gas fields, 1 gas pool, and 4 deeper pools. Several old gas pools and fields were extended by development drilling. In the Youngsville-Sugar Grove oil field of Warren County, where 132 oil wells were drilled, daily production reached a high of 1,700 b per d of crude oil. Greatest density of deeper drilling was in northwestern Pennsylvania in the Medina (Lower Silurian) gas pools. There were 700 new wells drilled and 26 wells deepened. Oil pipeline runs totaled 5,014,000 bbls of crude oil; reserves were estimated at 91,734,000 bbls at the year end. Gas production totaled 92,340,000 Mcf, and reserves were estimated at 1,214,498,000 Mcf. The total reservoir capacity for storage of natural gas is 512,000,000 Mcf.