J. Spivak, O. B. Shelburne, 1971. "Future Hydrocarbon Potential of Atlantic Coastal Province", Future Petroleum Provinces of the United States—Their Geology and Potential, Volumes 1 & 2, Ira H. Cram
Download citation file:
Although no fields have been found to date in the United States part of the Atlantic Coast north of Florida, large speculative reserves of oil and gas are believed to be present beneath the coastal plain, continental shelf, and continental slope. Speculative recoveries estimated from volume of sedimentary rocks are 13 billion bbl of petroleum and natural gas liquids and 74 trillion cu ft of gas. Ninety percent of these predicted reserves is offshore, and most accumulations are expected to be found north of Cape Fear.
The Atlantic Coastal province is an untested area. Onshore, there is one well per 390 sq mi (1,010 sq km). Offshore, there are no wells in the 118,000 sq mi (305,600 sq km) lying beyond inland waters.
Well control on the coastal plain has revealed a seaward-dipping and seaward-thickening wedge of Cretaceous and Tertiary rocks. The extension of this wedge can be extrapolated beneath the continental shelf and slope with the aid of seismic refraction data and sea- floor samples. Coarse continental clastic beds in updip exposures grade into finer grained clastic beds and increase in percentage of marine beds seaward. Carbonate beds predominate south of Cape Fear and clastic beds predominate northward. Potential hydrocarbon- bearing rocks range in age from Miocene to Early Cretaceous. Older sedimentary rocks with potential may be discovered offshore. The sedimentary sequence on the shelf averages 7,500 ft (2,290 m) in thickness and reaches 16,000 ft (4,880 m) off New Jersey. It continues to thicken beneath the continental slope and may exceed 30,000 ft (9,140 m) on the Blake Plateau. Onshore well data and offshore bottom samples indicate that most of the sediments were deposited in transitional or shallow-marine environments, which should assure the presence of potential reservoirs and source beds.
Figures & Tables
Future Petroleum Provinces of the United States—Their Geology and Potential, Volumes 1 & 2
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.