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U.S. Geological Survey
Fact Sheet 024-01 Online Version 1.0

The National Petroleum Reserve-Alaska (NPRA) Data Archive

By Kenneth J. Bird

The area currently known as the National Petroleum Reserve­Alaska was originally designated in 1923 as Naval Petroleum Reserve No. 4 (NPR­4). It was one of four U.S. regions thought to contain significant amounts of oil that were to be reserved for national crises. Geographic and geologic knowledge of the NPR­4 was only superficial in 1923. Earlier exploration, however, had shown that the region contained the ingredients necessary for oil accumulations to exist: source rocks, reservoir rocks, and geologic structures that could trap petroleum. Oil seeps on the coast and the size of the area (some 37,000 square miles, about the size of Indiana) reinforced the notion that significant quantities of petroleum were present.

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URL of this page: https://pubs.usgs.gov/factsheet/fs024-01/
Maintained by: Eastern Publications Group Web Team
Created 04/10/01
Last modified: 04/10/01 (krw)