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The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 65 (1981)

Issue: 5. (May)

First Page: 909

Last Page: 909

Title: Morphology, Sedimentology, and Genesis of Three Large Submarine Canyons Adjacent to Navarin Basin, Bering Sea: ABSTRACT

Author(s): Paul R. Carlson, Herman A. Karl, Kenneth A. Johnson

Article Type: Meeting abstract

Abstract:

Three large submarine canyons cut deeply into the Bering Sea margin adjacent to the Navarin basin, a prospective petroleum province scheduled for leasing in 1984. These canyons, Navarinsky, Pervenets, and Zhemchug, Previous HitheadNext Hit in water shallower than 150 m, extend seaward as far as 230 km, and debouch onto extensive deep-sea fans at depths of 3,200 m. The three canyons are incised as deeply as 2,400 m into Neogene and older more lithified Paleogene rocks that make up much of Navarin basin. These canyons are apparently controlled by structures dating back to the Paleogene. Major cutting of the canyons probably occurred when lowered sea levels exposed the Bering shelf and allowed such large rivers as the Yukon to carry large amounts of sediment to the outer shelf. Slumping and the resulting turbidity currents are the most likely canyon-cutting processes. Seismic-reflection profiles across and down the canyons indicate that numerous slumps and well-developed cut-and-fill structures are present throughout the canyon systems. The large width of the modern Bering Sea shelf may have resulted in low rates of sediment accumulation on the outer shelf during present highstands of sea level. However, the presence of a few graded sand layers in 2 to 5-m cores recovered from the canyons and their fans suggest at least some occasional ongoing turbidity-current activity in these canyons. Extensive fields of sand Previous HitwavesNext Hit have recently been discovered at the heads of all three canyons. Preliminary interpretations of geophysical data indicate that these sand Previous HitwavesTop are relict feature that formed at times of lower sea level during glacial episodes.

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