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Marine Geology and Geophysics Group

Marine Geology and Geophysics Group

photo Marine Geology and Geophysics Group
Group Leader
Toshiya KANAMATSU

  • Research on seafloor deformation and structure, material and heat and fluid circulation below the seafloor through marine geological and geophysical observation
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Marine Geology and Geophysics Group

In 2011, a great earthquake of magnitude 9.0 (off the Pacifi c coast of Tohoku Earthquake) occurred with a maximum seismic intensity of 7, and a giant tsunami attacked the eastern coast of the Tohoku region. To clarify what happened in the Japan Trench and the detailed mechanism of the earthquake and tsunami, JAMSTEC started research immediately after the earthquake, and geological, bathymetric, and other studies revealed a large displacement of the seafl oor and movement of the slope on the landward side of the trench axis. Also, by capturing the Tsunami-induced magnetic field, we successfully identified the location where the short-period tsunami that is supposed to have caused the tsunami to become sohuge, occurred. On the other hand, the importance of understanding, from various angles, the situation of the seismogenic zone before
the earthquake occurred and what had happened in past earthquakes was recognized again. Accordingly, to understand the phenomena and past events around the plate subduction zone where great earthquakes and tsunamis occur, the Marine Geology and Geophysics Group focuses on phenomena, such as seafl oor variation, fluid and heat circulation below the seafloor and alteration of the oceanic crust at the time of an earthquake, and promotes research using a variety of techniques, such as geological, geomorphological, electromagnetic observations, gravity, and geomagnetism analyses. For this research, we perform observations using research ships, remotely operated vehicles and deep tow. We also focus on technology development, for example, we are now working on a new electromagnetic technique for improving the accuracy of fluid distribution imaging.


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A scene of marine geological and geophysical observation
To capture various phenomena around seismogenic zones, we perform research using a broad range of techniques, such as high-accuracy and wide-area mapping, sedment sampling, geophysical and electromagnetic observation.
A scene of submergence of OBEM.