魚群探知機エコーとGPS測位によるメタンプルーム位置特定

Abstract

In this study, the authors identified the position of a methane plume in the Joetsu Basin by analyzing echo sounder images and GPS data. First, the authors observed the methane plume echo imagery, obtained using a quantitative echo sounder during a research cruise aboard JAMSTEC research vessel “Natsushima” in August 2013. Then the authors conducted two research cruises aboard the Nagasaki University training ship “Nagasaki-maru” during May 2014 and May 2015. During the 2014 cruise, the authors observed methane plume echo images at the position identified from the 2013 cruise data. During the 2015 cruise, the authors performed sea bottom core sampling at the same position using the methane plume echo imagery, and successfully obtained a methane hydrate core sample from the seafloor at a depth of approximately 560 m.