Opportunities and Priorities in Arctic Geoscience (1991) / Chapter Skim
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6 Logistic Realities and Opportunities
6 Logistic Realities and Opportunities
Pages 46-55
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From page 46... ...
The overriding problem for solid-earth geoscience in the Arctic Ocean Basin has, of course, been its inaccessibility to standard marine research vessels and drill ships. Recent cruises of icebreakers to high latitudes within the arctic ice pack and of Soviet nuclear icebreakers to the North Pole suggest that this barrier will soon be broken.
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From page 47... ...
INSTRUMENTATION The recent development of new geophysical instruments and the continuing reduction in size and weight of others will greatly advance solid-earth geoscience research in the Arctic. Important examples of such instruments are small digital recorders that can be deployed in long seismic refraction arrays on sea ice in late winter and spring, digital recorders capable of recording and processing 16 or more channels of seismic reflection data that are sufficiently rugged and compact to operate on sleds during field operations in the Arctic, gravity systems that can achieve accuracies of 3 or 4 meals from airplanes or helicopters, and long-range side-scan imaging and digital bathymetric mapping systems that can image and map the seafloor from submarines.
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From page 48... ...
AIRCRAFT Logistic Support Airplanes have been central to Arctic Ocean Basin research ever since personnel of the Soviet All-Union Arctic Institute' led by I.D. Papanin, used airplanes to establish a drifting scientific station on sea ice at the North Pole in 1937.
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From page 49... ...
49 Ice Floes and Ice Islands Ice stations on ice floes, especially on ice islands (tabular icebergs with high freeboard that are of glacial origin) , are ideal facilities for long-term oceanographic and weather observations in the central Arctic Ocean Basin.
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From page 50... ...
In this season, when the ice pack reaches its annual minimum position and icebreakers can penetrate it most easily, air cushion vehicles or amphibious craft that can traverse both open water and rough sea ice may be able to provide logistic support for seismic reflection, seismic refraction, and other geoscience studies from sea ice. Such vehicles, of which the amphibious ARKTOS, developed by Watercraft Offshore Canada, Ltd.
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From page 51... ...
The Polar class icebreakers in the United States and the Ermak class diesel and the Arktika class nuclear icebreakers in the USSR allow scientific investigation of the central Arctic Ocean Basin, whereas the earlier vessel classes could work only in the basin margins. Harbingers of this revolution are the cruise of the West German polar research vessel Polarstern to 86°22,N in 1987 to conduct multidisciplinary research; the voyages of the Arktika and Sibir to the North Pole in 1977 and 1987, during which geophysical data were collected; and the cruise of the Polar Star to the Northwind Ridge in 1988 to collect geophysical data and cores.
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From page 52... ...
Employment of one of these ships for a tourist cruise to the North Pole in 1990 and solicitations for passengers for a second cruise in 1991 suggests that Soviet nuclear icebreakers will be available for charter by western scientists seeking research platforms in the Arctic Ocean Basin. With the cancellation of the Canadian Polar 8 icebreaker, there will be no existing or prospective North American ship that alone can routinely support scientific work in the central Arctic Ocean Basin.
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From page 53... ...
Submarines are uniquely suited, however, for acquiring regional bathymetric, side-scan sonar and probably highfrequency, shallow-penetration seismic reflection data beneath the polar ice pack. Furthermore, there are no alternative platforms for acquiring such data uniformly over the entire Arctic Ocean Basin or even large subregions thereof, although ships may be more cost-effective for research in certain areas of the basin.
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From page 54... ...
Field experience suggests that the ratio of Cretaceous and Tertiary to Quaternary cores in the Arctic would increase significantly if piston core sites were chosen on ridge crests and slopes on the basis of bathymetric criteria or seismic reflection profiles, if ships or air-mobile coring stations were placed over specific stratigraphic targets, and if the improved coring devices now under development were able to obtain deeper subbottom penetrations. High-resolution seismic reflection data would be invaluable for achieving deeper stratigraphic penetration by identifying sampling sites where Quaternary sediment, which almost everywhere mantles bedrock in the Arctic Ocean Basin, is thin.
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From page 55... ...
Even with icebreaker support, existing drill ships-including the Ocean Drilling Program's JOIDES Resolution are not sufficiently ice strengthened to maneuver safely within the main polar ice pack. Sedimentary fill in the Canada and Makarov Basins ranges from 6 to 12 km or more, and its upper part is inferred to consist of Late Cenozoic turbidites that are of secondary interest for determining the environmental history of these basins.
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