Elucidation of the marine ecosystem fluctuation mechanism in the Sanriku offshore area
Period and Interval2015/04/03 - 2015/04/12
CategoryResearch Cruise
OverviewThe purpose of this cruise is to understand the impacts to marine ecosystems by the 2011 Earthquake off the Pacific coast of Tohoku) and Tsunami, and to contribute by marine science aspects to recover and rebuild of Sanriku fisheries activities. Target areas are sea bottom layers off Sanriku. This cruise is conducted under the TEAMS project, namely Tohoku Ecosystem Array of Marine Sciences. Detail investigation subjects are topographic surveys, mapping of scattered debris, distribution patterns and diversity of benthic organisms, seawater and sediments chemical and sediment components. Based on these data and samples, we will construct habitat map for ecosystem management in Sanriku areas.
In this cruise, we obtained acoustic data to fully understand the recent bathymetry, seafloor condition. To obtain higher accuracy data for correcting the current seafloor condition including marine earthquake debris, we used a towing side scan sonar with 120 kHz and 410 kHz acoustic signals. We could detect an anomalous object like a sunken ship at the depth of 900 m off Aomori prefecture, and obtained the detailed images in a submarine canyon off Otsuchi. Moreover, the synthetic aperture sonar (SAS) system developed by JAMSTEC was also used around the shallow area to obtain very fine acoustic images of seafloor. We also conducted the shipboard MBES survey.
Research Point Table
Polygon | Coordinates | 37.5,141.4605/37.5,143.5/40.5,143.5/40.5,142.3614/40.52233,142.3614 |
---|
|
Research Point Map & Track Chart Map & Point List
Results and Future PlanIn this cruise, we obtained acoustic data to fully understand the recent bathymetry, seafloor condition. To obtain higher accuracy data for correcting the current seafloor condition including marine earthquake debris, we used a towing side scan sonar with 120 kHz and 410 kHz acoustic signals. Moreover, the synthetic aperture sonar (SAS) system developed by JAMSTEC was also used around the shallow area to obtain very fine acoustic images of seafloor. We also conducted the shipboard MBES survey.