Arctic Oceanographic Measurements from Drifting Ice Islands. (1). Gravity Observations. (2).

Investigations in hydroacoustics and marine geophysics were conducted from two drifting ice stations, T-3 and Arlis II, in the Arctic Ocean. Long range sound propagation experiments were made over a number of paths between ice stations and also with icebreakers. The signals from explosives are trans...

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Bibliographic Details
Main Authors: Hunkins,Kenneth L., Talwani,Manik
Other Authors: LAMONT-DOHERTY GEOLOGICAL OBSERVATORY PALISADES N Y
Format: Text
Language:English
Published: 1971
Subjects:
Ice
Online Access:http://www.dtic.mil/docs/citations/AD0728803
http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0728803
Description
Summary:Investigations in hydroacoustics and marine geophysics were conducted from two drifting ice stations, T-3 and Arlis II, in the Arctic Ocean. Long range sound propagation experiments were made over a number of paths between ice stations and also with icebreakers. The signals from explosives are transmitted to great ranges in the Arctic surface SOFAR channel. The character of these signals is explained in principal by both ray and mode theory. Background noise is created by cracking and crushing of the ice cover. The sources and variability of the background noise are discussed. Geophysical investigations included navigation, ocean depth, gravity and magnetics. Marine geological investigations included bottom photography, nephelometry and coring. Improvement of accuracy of sea gravity measurements by consideration of the cross coupling and off leveling errors is discussed. The use of satellite navigation for increasing navigational accuracy and hence the accuracy of gravity measurements is described. (Author)