July 3, 2000
Japan Marine Science and Technology Center


Deployment of Ocean Bottom Seismometers by the SHOUYOUin the Waters around the Isle of MIYAKE

The Japan Marine Science and Technology Center (CEO: Takuya Hirano) plans to conduct a series of maneuvering earthquake observations using ocean bottom seismometers (OBS) jointly with the Maritime Safety Agency and the Earthquake Research Institute of the University of Tokyo. The OBSfes are to be deployed between the isles of MIYAKE to KOHZU where a series of seismic activities has actively occurred since the 26th of June following a volcanic crisis at the isle of MIYAKE.

These OBS observations will be carried out in parallel with the other ocean bottom geosurveys by the Maritime Safety Agency. The objective is not only to provide seismic observation data to the organizations related to the prediction of earthquakes and volcanic eruptions, but to explicate, through high-precision observations, the crust stress releasing mechanism in the ocean bottom area where earthquake swarms are often occurring.

14 self pop-up type ocean bottom seismometers will be deployed by the g SHOUYOUh, one of survey vessels of the Maritime Safety Agency, in the period of July 7 to 9. Among these seismometers, eight of them are owned by the Maritime Safety Agency, 1 by the Seismic Research Institute of the University of Tokyo, and the rest of 5 (wide-band seismometers) by the Japan Marine Science and Technology Center, respectively. These seismometers will be recovered after the 1- to 2-month observations.

Today (July 3), the Maritime Safety Agency announced a press-release on this research project. On the 2nd of July, 6 seismometers from the Earthquake Research Institute, the University of Tokyo had already been installed in the subject area. In addition of the 14 additional instruments, total 19 seismometers will be deployed in and around the seismic swarm region except one recovered already for quick-look interpretation of the seismic activity.

Contact : H. Mikada, Deep Sea Research Department
Japan Marine Science and Technology Center
Tel: 0468-67-3982
Y. Taya, Public Relations Division, Administration Department
Tel: 0468-67-3806

Wide-band seismometer: Seismometers which can record wideband data ranging from several tens to 0.05 Hz or much lower frequency than the other ordinary types of instruments can.