Petroleum geology of Kodiak Shelf, Alaska.

Michael A. Fisher

doi:10.1306/2f919454-16ce-11d7-8645000102c1865d

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Petroleum geology of Kodiak Shelf, Alaska.

Michael A. Fisher

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Abstract

Organic geochemical data show that Cenozoic rocks on Kodiak Island, in Albatross basin, and under the continental slope generally contain less than 0.5 wt. % organic carbon. Moreover, kerogen from all rocks analyzed is predominantly (60 to 100%) herbaceous; woody and coaly kerogens are present in secondary (20 to 40%) amounts. Most strata in shelf basins are thermally immature; however, Eocene and Oligocene strata, which probably floor the shelf basins, are mature on the basis of comparison with coeval strata onshore. Eocene and Oligocene rocks have poor reservoir properties; the best reservoirs are probably in upper Miocene or Pliocene and younger rocks. Potential traps for hydrocarbons include Tugidak uplift, parts of Albatross Bank, structures in the central-shelf upli t, and Portlock anticline. Overall, unless hydrocarbon source rock properties improve offshore, gas and gas condensate are the most likely hydrocarbons to have been generated.

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American Association of Petroleum Geologists Bulletin Article

Source-reported bounding extent: 55.219278425030836° to 58.87849102063663° latitude; -157.04675941117267° to -148.41023346491082° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Michael A. Fisher. 1980. Petroleum geology of Kodiak Shelf, Alaska.. https://doi.org/10.1306/2f919454-16ce-11d7-8645000102c1865d

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