HOW MUCH OIL & GAS IS IN ANWR'S COASTAL PLAIN?
High potential. The high potential for significant discoveries of oil and gas in ANWR has long been recognized. Early explorers of the region at the turn of the century, found oil seeps and oil-stained sands. However, since ANWR was established in 1960, exploration in the region has been restricted to surface geological investigations, aeromagnetic surveys, and two winter seismic surveys (in 1983-84 and 1984-85). No exploratory drilling has been accomplished in the area except for one well commenced in the winter of 1984-85 on Kaktovik Inupiat Corporation and Arctic Slope Regional Corporation lands southeast of Kaktovik on the Coastal Plain.
Location to big finds. Although little oil and gas exploration has taken place in ANWR, the Coastal Plain is believed to have economically recoverable oil resources. The Coastal Plain lies between two known major discovery areas. About 65 miles to the west of the Coastal Plain, the Prudhoe Bay, Lisburne, Endicott, Milne Point, and Kuparuk oil fields are currently in production. Approximately 1.5 million barrels of oil a day are produced from these fields, representing 25% of our domestic production. To the east of the Coastal Plain, major discoveries have been made in Canada, near the Mackenzie River Delta and in the Beaufort Sea.
U.S. Geological Survey - 1980. In 1980, the U.S. Geological Survey estimated the Coastal Plain could contain up to 17 billion barrels of oil and 34 trillion cubic feet of natural gas.
U.S. Department of Interior - 1987. After several years of surface geological investigations, aeromagnetic surveys, and two winter seismic surveys (in 1983-84 and 1984-85), the U.S. Department of Interior (DOI), in its April, 1987 report on the oil and gas potential of the Coastal Plain, estimated that there are billions of barrels of oil to be discovered in the area. DOI estimates that "in-place resources" range from 4.8 billion to 29.4 billion barrels of oil. Recoverable oil estimates ranges from 600 million barrels at the low end to 9.2 billion barrels at the high end. They also reported identifying 26 separate oil and gas prospects in the Coastal Plain that could each contain "super giant" fields (500 million barrels or more).
U.S. Geological Survey - 1998. The most recent petroleum assessment prepared by the USGS in 1998 (OFR 98-34), increased the estimate for technically recoverable mean crude oil resources. (See Oil in the ANWR? It's Time to Find Out!)
Only drilling will tell. The geologic indicators are very favorable for the presence of significant oil and gas resources in ANWR, but the limited data means that there is a high level of uncertainty about how much oil and gas may be present. Consequently, current estimates represent the best scientific guesses. However, most geologists agree that the potential is on the order of billions of barrels of recoverable oil and trillions of cubic feet of recoverable gas and that these resources may rival or exceed the initial reserves at Prudhoe Bay. The validity of these estimates can be proved only by drilling exploratory wells. Authorization for exploration must be given by Congress and the President.
In 1996 the North Slope oil fields produced about 1.5 million barrels of oil per day, or approximately 25 percent of the U.S. domestic production. However, Prudhoe Bay, which accounts for over half of North Slope production, began its decline in 1988, and no new fields have yet been discovered with the potential to compensate for that decline.