Biogenic and thermogenic origins of natural gas in Cook Inlet basin, Alaska.

George E. Claypool; C. N. Threlkeld; L. B. Magoon

doi:10.1306/2f91944f-16ce-11d7-8645000102c1865d

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Biogenic and thermogenic origins of natural gas in Cook Inlet basin, Alaska.

George E. Claypool·C. N. Threlkeld·L. B. Magoon

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Abstract

Two types of natural gas occurrences are present in the Cook Inlet basin. The major reserves (1.8 × 10 11 m 3 ) occur in shallow (less than 2,300 m), nonassociated dry gas fields that contain methane with ^dgr 13 C in the range of -63 to -56 per mil. These gas fields are in sandstones interbedded with coals of the Sterling and Beluga Formations; the gas fields are interpreted as biogenic in origin. Lesser reserves (1.1 × 10 10 m 3 ) of natural gas are associated with oil in the deeper Hemlock Conglomerate at the base of the Tertiary section; associated gas contains methane with ^dgr 13 C of about -46 per mil. The gases associated with oil in the Hemlock Conglomerate are thermogenic in origin.

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American Association of Petroleum Geologists Bulletin Article

Source-reported bounding extent: 60.06806650089854° to 61.603912894724544° latitude; -152.8066533859104° to -148.73008290693286° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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George E. Claypool, C. N. Threlkeld, L. B. Magoon. 1980. Biogenic and thermogenic origins of natural gas in Cook Inlet basin, Alaska.. https://doi.org/10.1306/2f91944f-16ce-11d7-8645000102c1865d

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