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GRAVIMETRY

At least two of a set of 4 quartz thermally stabilized model GMN-K gravimeters assembled in Russia by Vniigeofisika were running during multibeam lines and medium range transits. The sensors were mounted on gyroscopic platforms very close to ship's center of gravity. Their height above sea level was measured to be 0.7 m. The instruments had a resolution of 0.04 mGal, and were equipped with a circuitry to reduce noise due to high waves. In the ports of Durban and Abidjian (see Tab.5) the instruments were calibrated on known reference points with a portable gravimeter Lacoste and Romberg Mod.G-327.


Table 5: Gravimeter calibration.
DATE SITE REFERENCE SHIP
1996-03-07 Durban 979348.66 +/- 0.02 979352.32
1996-05-09 Abidjian    


Since the pattern of planned profiles was predominantly E-W, some N-S connecting lines were run for control. In addition, ship went to the Island of Bouvet crossing 1994 line pattern and repeating a 1994 station in anchor.


next up previous contents
Next: SEABED SAMPLING Up: MATERIALS AND METHODS Previous: MAGNETOMETRY   Contents
2008-01-01