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Abstract
Seismic reflection and refraction data were collected in generally ice-covered waters of the Canada Basin and the
eastern part of the Chukchi Continental Borderland of the Amerasia Basin, Arctic Ocean, during the late summers of
1988, 1992, and 1993. The data were acquired from a Polar class icebreaker, the U.S. Coast Guard Cutter Polar
Star, using a seismic reflection system designed by the U.S. Geological Survey (USGS). The northernmost data extend
to 78° 48' N latitude.
In 1988, 155 km of reflection data were acquired with a prototype system consisting of a single 195 cubic inch air
gun seismic source and a two-channel hydrophone streamer with a 150-m active section. In 1992 and 1993, 500
and 1,900 km, respectively, of seismic reflection profile data were acquired with an improved six air gun, 674 to
1303 cubic inch tuned seismic source array and the same two-channel streamer. In 1993, a 12-channel streamer
with a 150-m active section was used to record five of the reflection lines and one line was acquired using a three
air gun, 3,000 cubic inch source. All data were recorded with a DFS-V digital seismic recorder. Processed sections
feature high quality vertical incidence images to more than 6 km of sub-bottom penetration in the Canada Basin.
Refraction data were acquired with U.S. Navy sonobuoys recorded simultaneously with the seismic reflection profiles. In
1988 eight refraction profiles were recorded with the single air gun, and in 1992 and 1993 a total of 47 refraction profiles
were recorded with the six air gun array. The sonobuoy refraction records, with offsets up to 35 km, provide acoustic
velocity information to complement the short-offset reflection data.
The report includes trackline maps showing the location of the data, as well as both digital data files (SEG-Y) and images
of all of the profiles.
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