A research team comprising members from the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), the Earthquake Research Institute of the University of Tokyo, the Faculty of Science at Hokkaido University, the Graduate School of Science and Faculty of science at Tohoku University, the Graduate School of Science, Faculty of Science at Chiba University, the Course of Marine Resources and Environment, the Graduate School of Marine Science and Technology at Tokyo University of Marine Science and Technology, the School of Marine Science and Technology at Tokai University, the Disaster Prevention Research Institute at Kyoto University, the Graduate School of Science at the University of Hyogo, and the Graduate School of Science and Engineering at Kagoshima University announced on February 16 that they were launching their second emergency survey navigation after the 2024 Noto Peninsula Earthquake. They will be conducting research aboard the Hakuho Maru, a scientific survey boat owned by JAMSTEC. The research team will be collecting some of the ocean-bottom seismometers (OBSs) they installed in January as well as installing new measuring equipment.
On this survey trip, they will collect 26 of the 34 OBS units they installed in January as well as all of the two ocean-bottom electromagnetometers (OBEMs) installed then. Moreover, they will install 20 OBS and approximately 5 OBEM units. The navigation started on February 19 and ended on March 1 at Toyama Shinko Port. Acoustic communication is used to cut each OBS and OBEM unit loose from its weight, after which the units float to the sea surface where they are collected by the researchers. The rest of the measuring equipment, which will remain in the waters to collect more measurements, will likely be retrieved in the summer. The research team will analyze the data to reveal the actual state of the faults that triggered the 2024 earthquakes. They will also attempt to reveal the mechanism that activates earthquakes and/or tsunamis to determine the changes of the ongoing seismic activities.
The group will again board the Hakuho Maru for their planned third survey navigation, during which they will examine the structure of the earthquake source fault.
This article has been translated by JST with permission from The Science News Ltd. (https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.