In eastern Pennsylvania the stratigraphic sequence ranges in age from Early Cambrian to Early Pennsylvanian; in southeastern Pennsylvania, Triassic rocks are present also. It is estimated that the total section is more than 30,000 ft (9,140 m) thick adjacent to the Appalachian front in east-central Pennsylvania. Satisfactory reservoir rocks are present throughout the stratigraphic sequence, and adequate source materials are also evident.
Northeastern Pennsylvania (Pocono-Catskill region) is in the Appalachian Plateau province. Southeastern Pennsylvania is within the Valley and Ridge and Piedmont provinces. Many local structures are present in the report area.
All of the Pennsylvania oil and gas production- now is centered in western Pennsylvania. Only one small subcommercial gas pool has been discovered in eastern Pennsylvania in Lackawanna County.
The Pocono-Catskill region offers the best prospects for future production. The folded and faulted Valley and Ridge province is somewhat prospective, but the Piedmont province, including Triassic basinal rocks, is not a likely future petroleum province. Cambrian through Devonian strata are considered the most promising as reservoirs of undiscovered hydrocarbons in eastern Pennsylvania.
Nearness to the highly populated metropolitan areas along the eastern seaboard and the need for locating suitable structures for underground storage of natural gas offer some inducements for future petroleum exploration in eastern Pennsylvania.
Northern New Jersey is included in the report area. It does not appear to be as promising an area for future petroleum production as eastern Pennsylvania.
Figures & Tables
The geology of the entire United States, including the continental shelf and slope, was studied by petroleum geologists to determine its petroleum potential. Prospective areas of the 11 regions were assessed qualitatively and, usually, quantitatively.
The prospective basinal area covers approximately 3.2 million sq mi (statute; 8.3 million sq km) and contains approximately 6 million cu mi (25 million cu km) of sedimentary rock above basement or 30,000 ft (9,144 m). Other less prospective areas are, in the aggregate, large.
The prospective area has not been explored adequately. Many high-potential areas are indicated by the geology and extent of exploration, particularly in parts of Alaska, California, Colorado, Louisiana, Mississippi, Montana, New Mexico, North Dakota, Oklahoma, Texas, Utah, and Wyoming, and in parts of the offshore of Alaska, California, Louisiana, and Texas. The prospective Atlantic, Florida, and Alaska continental shelves, and the entire continental slope, barely have been touched by drilling, and other prospective areas and depths on land and the continental shelf remain largely unexplored.
Estimates of potential crude oil reserves of the basinal area only, exclusive of known reserves, range from 227 to 436 billion bbl of original oil in place. The potential probably exceeds the mean of 332 billion bbl. Approximately 32 percent of the oil in place would be recoverable at known rates of recovery. Ultimately, the rate of recovery may reach 60 percent.
Estimates of potential natural gas reserves exclusive of known reserves range from 595 to 1,227 trillion cu ft of recoverable natural gas. The gas potential also probably exceeds the mean of 911 trillion cu ft.
The ultimate petroleum potential of the United States, including known reserves, may exceed 432 billion bbl of crude oil, 1,543 trillion cu ft of natural gas, and 49 billion bbl of natural gas liquids.
Finding and developing the large petroleum potential will require a great amount of drilling because a significant percentage of the visualized undiscovered crude oil and natural gas is in stratigraphic traps, combination stratigraphic and structural traps, reefs, and complex structural situations. Estimates of future domestic demand call for accelerated exploration. To the extent that policies of industry and government militate against accelerated exploration, particularly drilling, a high percentage of the petroleum resources of the United States will not be reduced to possession.