DEEP MAGNETIC SURVEY ENGINEERING METHOD USING LARGE-SIZED SURVEY FRAME WITH UNDERWATER SOUND RANGE FINDER

摘要

PROBLEM TO BE SOLVED: To provide a magnetic survey engineering method by which magnetic survey can be carried out efficiently by locating points showing magnetic anomalies with high accuracy even on the relatively deep sea bottom. SOLUTION: An A-frame 11 and a depth adjusting winch 17 are provided on a survey pontoon 12 so that a large-sized survey frame 10 which is provided with an underwater sound range finder and echo sounder, incorporated with a plurality of magnetic sensors, and is constructed by combining nonmagnetic pipes can be lifted up and housed in the pontoon 12. The frame 10 is lowered into the sea until the frame 10 approaches the bottom of the sea from the pontoon 12 to which the transceivers 30 and 9 of the range finder and echo sounder are attached and the sea bottom is magnetically surveyed by respectively towing the pontoon 12 and frame 10 with a towing ship 14 through ropes 15 and 16.