USGS Releases Estimate of Conventional Oil and Gas in Alaska Central North Slope

Assessment Also Includes Estimate for 8.9 Trillion Cubic Feet of Natural Gas

By Communications and Publishing January 23, 2020

USGS continues its estimates of technically recoverable oil and gas in Alaska's North Slope.

One of the most productive areas in the world for oil remains rich in the resource, according to the latest USGS assessment. The USGS estimates 3.6 billion barrels of oil and 8.9 trillion cubic feet of natural gas conventional resources in Alaska’s Central North Slope. This assessment does not include discoveries made by industry between 2013 and 2017.

“Alaska is synonymous with energy, and this assessment just reinforces that,” said USGS Director Jim Reilly. “The State of Alaska and its industry partners have responsibly produced billions of barrels of oil from Prudhoe Bay, and we think there are still billions more in this region that can be produced.”

click on image for full description — (Public domain.)

The assessment consists of six assessment units that range from significant oil resources to significant natural gas resources. Although the USGS assessed this region in 2005, increases in geologic knowledge and understanding of the rocks and resource potential allowed the USGS to focus more specifically on the six assessment units included in this estimate.

Alaska’s Central North Slope has long been known to be rich in oil and gas resources. The assessment area hosts most of the producing oil and gas fields in Arctic Alaska, and the 800-mile-long Trans-Alaska Pipeline spans most of the region.

Image shows a bar chart with two bars, one for the 2005 assessment and one for the 2020 assessment — In 2005, the USGS assessed some of the same areas as the 2020 assessment. In the 2020 assessment, mean oil is slightly lower, however about 2.1 billion barrels of oil was assessed in non-Federal areas outside NPR-A, mainly the Central North slope, as part of the 2017 Nanushuk – Torok assessment: https://pubs.er.usgs.gov/publication/fs20173088. In addition, more than one billion barrels of oil have been discovered in the Central North Slope since 2005 by industry.

The supergiant Prudhoe Bay field is within the assessed area, which lies between the National Petroleum Reserve-Alaska to the west, the Brooks Range to the south and the Arctic National Wildlife Refuge to the east.

Most of the lands in the Central North Slope are owned by the State of Alaska and Alaskan Native Corporations.

The resources estimated in this report are undiscovered, technically recoverable conventional resources. Conventional resources are those that have collected into discrete accumulations that can be produced using traditional production techniques. These are in contrast to continuous resources, which are those spread throughout a rock layer and typically require enhanced recovery techniques such as hydraulic fracturing to produce.

Image shows a tent camp in the foreground with mountains in the background — Oil-industry base camp at Galbraith Lake.

Undiscovered resources are those that have been estimated to exist based on geology and other data, but have not yet been proven to exist by drilling or other means. Technically recoverable resources are those that can be produced using today’s standard industry practices and technology. This is different from reserves, which are those quantities of oil and gas that are currently profitable to produce.

The new assessment of the Alaska Central North Slope may be found here. To find out more about USGS energy assessments and other energy research, please visit the USGS Energy Resources Program website and follow us on Twitter.