Four quartz-stabilised russian NEFTEKIP, model GMN-K sea gravimeters were used in a noise-reduction configuration. The gravimeters had an accuracy of 1/2 mGal under accelerations of 100 Gal and the data was recorded digitally on a PC-based platform. Crossing lines were planned in order to obtain statistical parameters for optimum data reduction. In addition to this, two ground based measurments were taken in the port of Naples to serve as drift compensation and calibration points.