The Barrow gas fields, located a few miles south of Point Barrow, Alaska, on a northern extension of the Arctic coastal plain, constitute the most northerly producing area in the United States. The South Barrow gas field was discovered in 1949 under the exploration program supervised by the U.S. Navy. The East Barrow field proved productive in 1977, shortly before Congress transferred Naval Petroleum Reserve No. 4 (NPR-4) to the Department of the Interior and renamed it the National Petroleum Reserve in Alaska (NPRA).

The producing areas are regionally high near the intersection of two large structurally positive elements, the Barrow arch and the Meade arch. The section of sedimentary rocks above the metamorphic basement is thin in the producing fields, only about 760 m thick. The accumulations are structurally controlled and produce from a sandstone of Middle Jurassic age. The discovery wells were located on seismic anomalies that border a roughly circular "disturbed zone," of highly faulted rocks with erratic dips, that has been called an astrobleme or a cryptovolcanic structure. Additional untested seismic structures appear to be present in the area.

The older South Barrow field is the larger of the two fields, having original recoverable reserves of about 25 Bcf of gas. The newer East Barrow field has estimated recoverable reserves of about 12 Bcf of gas. The fields furnish fuel for facilities occupied by agencies of the federal government and the native village of Barrow. The costs of developing and producing the gas are high, but recent comparative studies have shown it to be the most economical fuel for the area.

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