Minimum distribution of subsea ice-bearing permafrost on the US Beaufort Sea continental shelf

Geophysical Research Letters
By: , and 

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Abstract

Starting in Late Pleistocene time (~19 ka), sea level rise inundated coastal zones worldwide. On some parts of the present-day circum-Arctic continental shelf, this led to flooding and thawing of formerly subaerial permafrost and probable dissociation of associated gas hydrates. Relict permafrost has never been systematically mapped along the 700-km-long U.S. Beaufort Sea continental shelf and is often assumed to extend to ~120 m water depth, the approximate amount of sea level rise since the Late Pleistocene. Here, 5,000 km of multichannel seismic (MCS) data acquired between 1977 and 1992 were examined for high-velocity (>2.3 km s−1) refractions consistent with ice-bearing, coarse-grained sediments. Permafrost refractions were identified along <5% of the tracklines at depths of ~5 to 470 m below the seafloor. The resulting map reveals the minimum extent of subsea ice-bearing permafrost, which does not extend seaward of 30 km offshore or beyond the 20 m isobath.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Minimum distribution of subsea ice-bearing permafrost on the US Beaufort Sea continental shelf
Series title Geophysical Research Letters
DOI 10.1029/2012GL052222
Volume 39
Issue 15
Year Published 2012
Language English
Publisher AGU
Contributing office(s) Woods Hole Coastal and Marine Science Center
Description L15501
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Geophysical Research Letters
Other Geospatial Beaufort Sea