An example of modern oil field development on Alaska's North Slope

The U.S. Geological Survey (USGS) estimates that about 100 billion barrels of oil in-place resources, including undiscovered oil, underlies the North Slope of Alaska alone—a far cry from expectations early in the State’s oil history.

About 10 billion barrels of recoverable oil is estimated to underlie each of the two main areas bordering the central slope’s main producing area on the east and west: the National Petroleum Reserve-Alaska (NPR-A) to the west and the Coastal Plain, or 1002 area, of the Arctic National Wildlife Refuge (ANWR) to the east.

Limited oil and gas leasing is allowed in NPR-A, following a string of significant nearby discoveries west of the Prudhoe Bay area centered on Alpine field, which started up in late 2000.

In addition to the billions of barrels of discovered and undiscovered conventional oil, Alaska’s North Slope also holds over 20 billion barrels of extremely viscous oil that is technically recoverable—perhaps the largest unexploited heavy oil resource in the United States. Industry has only begun to tap this resource, and the key to large-scale economic recovery may be a carbon dioxide enhanced oil recovery scheme. An AEO project affirmed CO2 EOR as the best approach in developing a water-alternating-gas oil recovery process for the North Slope’s shallow, viscous oil reservoirs. The study also pointed to the added environmental benefit of CO2 EOR injection as a means of sequestering this greenhouse gas. See project description.