The Japan Agency for Marine-Earth Science and Technology (JAMSTEC), as part of the Integrated Ocean Drilling Program (IODP), deployed the Deep-Sea Scientific Drilling Vessel Chikyu for 54 days from April 1 to May 24 to conduct the Expedition 343 for Japan Trench Fast Drilling Project.
After this expedition, repair of the D/V Chikyu’s azimuth thrusters and annual inspection was completed on June 22, and the vessel will conduct an expedition to install the observatory assembly that was postponed during the previous expedition.
The Integrated Ocean Drilling Program (IODP)
IODP is an international marine research drilling program dedicated to advancing scientific understanding of the Earth by monitoring and sampling subseafloor environments. Through multiple platforms, scientists explore IODP’s principal themes: the deep biosphere, environmental change, and solid Earth cycles. IODP has been in operation since October 2003, funded jointly by the Japan Ministry of Education, Culture, Sports, Science and Technology and by the U.S. National Science Foundation. Additional support is provided by the 18-member European Consortium of Ocean Research Drilling, the People’s Republic of China, the Republic of Korea, Australia, India, and New Zealand.
Japan Trench Fast Drilling Project (Expedition 343)
This project aims to study the frictional properties of the plate boundary fault that is believed to have caused the Tohoku Earthquake and associated tsunami. The drilling site was in the ocean area east of the Ojika Peninsula, Miyagi Prefecture (Figure 1), where an extremely large displacement of the seafloor had been inferred by previous research. Drilling was conducted from April 1 to May 24, 2012, from the seafloor to depth of the plate boundary, 850.5 meters below the seafloor. Along with collecting physical data on the formations, core samples were collected from 648 to 844.5 m below the seabed surface including the plate boundary fault. The planned installation of the observatory assembly in the borehole to measure the frictional heat at and near the plant boundary fault was rescheduled to July of this year due to problems with the cable for the underwater video camera system that was necessary for this work.
Source: JAMSTEC, June 29, 2012