Abstract
Near-bottom magnetic measurements provide us high-resolution magnetic anomaly. The high-resolution anomaly is valuable for the studies of the detailed magnetization structure of ocean crust and paleointensity recorded on the ocean crust. The measurements using a submersible have advantages to make the magnetometer system simple and to incorporate other observational results obtained by the submersible, such as seafloor pictures and samples that are informative for geology. A submersible usually moves at a height of several meters above seafloor, therefore the magnetic anomaly has a resolution of several meters. Magnetic measurements using the submersible Shinkai 6500 have been conducted several times, and experiences and scientific results have been accumulated. On the other hand, problems regarding the magnetic measurements were brought out. Because the submersible observation usually gives priority to geological observation, the navigation is not suitable for magnetic measurements. The restricted sensor position and the short track length are also disadvantages for the magnetic study. There is room for improvement in the magnetic calibration and operation. For the future, improvement of the measurement method is critically important. The near-bottom magnetic measurements with the submersible expand the range of the submersible study and provide additional information about lithology which may not be visible at the seafloor, and the seafloor age with a high resolution.
