Exploration in Pennsylvania during 1959 resulted in the discovery of 1 new gas field, 6 new gas pools, extended several gas-producing areas, and established a new producing-depth record in the state. A number of important dry exploratory tests were drilled during the year. The second offshore well in Pennsylvania, in Lake Erie on Block No. 2, was plugged and abandoned after finding salt water in the Gatesburg (Upper Cambrian) formation. The Block No. 2 lease has been surrendered. A second well will probably be drilled on Block No. 1 lease during 1960. In the Seven Springs field, Somerset County, a new-pool wildcat was successful when Pa. Tract 75 No. 3 by Peoples Natural Gas Company found gas in the Onondaga chert (Middle Devonian) at 8,472 ft. This is the deepest produci g-depth record in Pennsylvania. The well produced 10,933 MCF of gas without fracturing at a rock pressure of 3,400 psi in 10 days, and is the discovery well in the Kooser pool. Fayette County had the only new-field discovery in 1959. The Mueller-Herr well No. 1 by Manufacturers Light & Heat Company found gas in the Onondaga chert on the Laurel Hill anticline, resulting in the discovery of the Ohiopyle field.

Deep exploration (Middle Devonian or older) found 1 new gas field and 5 new gas pools. Of the unsuccessful wildcats, 10 were new-field wildcats and 7 were new-pool wildcats. Two outposts were unsuccessful. There were 83 development gas wells completed and 14 dry holes. The greatest density of deep drilling operations was in the Clearfield County area where the production limits of three pools, which had formerly been considered to be separate, were merged into one long field, the Punxsutawney-Driftwood field, extending almost 50 miles northeast and southwest. 122 deep wells were completed in Pennsylvania in 1959, with a total footage of 850,025 ft. Of the 122 wells, 89 were gas wells and 33 were dry holes.

A new shallow-sand (Upper Devonian or younger) gas pool was discovered when the Earl Young well No. 1 was drilled by James Drilling Company in Clearfield County. Production was from the Fifth sand. As in 1958 the secondary-recovery projects in the Bradford Field and the development drilling in the gas fields dominated the shallow-sand drilling activity during 1959. In all, 628 shallow-sand wells were completed. Of these, 215 were gas wells, 10 were oil wells, 54 were dry holes, and 7 were drilled for underground storage. 342 were drilled in connection with secondary-recovery oil operations. In addition to the 628 new wells, 29 shallow-sand wells were deepened. The total footage of the new and deepened wells was 1,452,759 ft.

Oil production decreased from 6,471,680 bbls. in 1958 to 6,160,387 bbls. in 1959. Proved oil reserves were estimated at 113,858,000 bbls. on December 31, 1959. Gas production increased from 104,974,000 MCF in 1958 to 118,862,000 MCF in 1959. Gas reserves were estimated at 1,051,972,000 MCF at the end of the year. More than 68,000 bbls. of distillate were produced in 1959. Companies leased more than 2,000,000 acres for oil and gas exploration. The total footage drilled, both shallow and deep, was 2,302,784 ft.