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By J. R. Woolsey

In late 1988, the Committee for Coordination of Joint Prospecting for Mineral Resources in South Pacific Offshore Areas (CCOP/SOPAC), Suva, Fiji, consulted the Continental Shelf Division of the Marine Minerals Technology Center regarding low-tech, low-cost, reconnaissance sampling systems for a variety of nearshore needs. Materials of interest to several member island nations included silica and calcareous aggregate for cement manufacture, sand for beach replenishment, heavy minerals, and precious metals. A principal criteria of the system was that it be of low-tech design, and as far as possible, suitable for construction on the islands from available materials. It should also be operable with SOPAC personnel on island vessels of opportunity. The system selected to satisfy these requirements was a convertible drill of basic airlift design, capable of operating with easy modification as either a vibralift or airlift, depending on the desired application. The basic system included a drill pipe constructed of heavy duty 76 mm (3") black iron pipe, divided into three 3 meter sections (for ease of transport), fitted with an air intake manifold and bit at the lower end. A 25 mm (1") galvanized pipe assembled in three similar sections and clamped to the drill pipe served as a water jet to assist in cutting. Air was supplied to the manifold by means of a 12 mm (1/2") pipe also clamped along the length of the drill pipe. Suitable hoses supplied water and air to the upper ends of the respective pipes by means

Jan 1, 1989

By Brian D. Bornhold

A comprehensive multi-disciplinary marine geological survey of northwestern Graham Island, Queen Charlotte Islands, British Columbia, Canada was conducted by Offshore Survey and Positioning Services Ltd. of Vancouver, B.C. on behalf of the Geological Survey of Canada; Energy, Mines & Resources Canada, Pacific Geoscience Centre, Sidney, B.C. Canada during October 1984 and July 1985. The aim of the survey was to map both the surficial geology and geomorphology in order to identify and evaluate the nature of the nearshore sedimentation and recent tectonics including stability (slumps and scarps) seafloor faults (frequency and displacements) and both the classification and consistency of soil type boundaries and properties. Data was acquired by utilizing conventional indirect applied marine geophysical techniques including side scan sonar, precision echo sounding and complimentary soil sampling. During October 1984 a total of 320 line kilometres of data including 180 soil samples were acquired. During July 1985 a total of 300 line kilometres of data were acquired including 150 soil samples.

Jan 1, 1985