Procédé et système pour étalonner des électrodes d'un cable marin dans un système de surveillance électromagnétique marine

摘要

A marine electromagnetic sensor system includes a sensor cable (10) having at least one electromagnetic sensor (12) thereon. A first calibration electrode (13A) is disposed on the cable on one side of the sensor. A second calibration electrode (13B) is disposed on the cable on an opposite side of the sensor. A calibration power supply (15) is coupled to the first and second calibration electrodes. A measuring circuit is coupled to the sensor. A method for calibrating marine electromagnetic survey electrodes includes imparting electric current between calibration electrodes disposed at spaced apart locations on a cable deployed in the water. Voltages impressed across a pair of electrodes disposed on the cable between the calibration electrodes are detected in response to the current. A change in sensitivity of the at least one pair of electrodes is determined using the detected voltages.