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The National Petroleum Reserve-Alaska (NPRA) data archive

April 1, 2001

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.

Publication Year 2001
Title The National Petroleum Reserve-Alaska (NPRA) data archive
DOI 10.3133/fs02401
Authors K. J. Bird
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Fact Sheet
Series Number 024-01
Index ID fs02401
Record Source USGS Publications Warehouse