Inc. seismic exploration crew,
Deadhorse, Alaska, 1981 Under the North Slope is an ancient seabed, which now contains large amounts of
petroleum. Within the North Slope, there is a geological feature called the Barrow Arch — a belt of the kind of rock known to be able to serve as a trap for oil. It runs from the city of
Utqiaġvik to a point just west of the Arctic National Wildlife Refuge.
Ira Harkey quotes
Noel Wien as stating that in the 1920s, "To keep warm and to cook with, the
Eskimo was burning hunks of dark stuff he just picked up on the ground all around his tent. This was oil from seepage under the tundra. The Eskimos had always known about the oil, long before there was any drilling for it." The North Slope region includes the
National Petroleum Reserve–Alaska (NPRA), which was established by President
Warren G. Harding in 1923 as an oil supply for the US Navy, though the presence of oil in the region had been known by American whalers for some time. In 2005 the USGS estimated that the Arctic Alaska Petroleum Province, encompassing all the lands and adjacent Continental Shelf areas north of the Brooks Range-Herald arch (see map) held more than 50 billion bbl of
oil and
natural-gas liquids and 227 trillion cubic feet of gas. Alaska North Slope (ANS) is a more expensive waterborne crude oil. Since 1987, Alaska North Slope (ANS) crude production has been in decline. As of 2020, the
U.S. Geological Survey estimated 3.6 billion barrels of oil and 8.9 trillion cubic feet of natural gas in
Mississippian through
Paleogene strata in the central North Slope of Alaska, which are undiscovered and technically recoverable. == See also ==