Submarine topography in the east sea of Minami-Tori Shima Island, North West Pacific Ocean

Abstract

Japan Coast Guard has carried out the bathymetric surveys in the eastern sea of the Minami!Tori Shima Island, North West Pacific Ocean since 1998 to 2008. The precise bathymetric data acquired in these surveys reveal the details of the submarine topography, and clusters of small conical volcanoes were discovered. The cluster which is located at southeast of Minami!Tori Shima Island is the largest (80km x 50km) in this area. Almost all cones which belong to the cluster are hundred meters in height and less than 10km in diameter. Considering the size and the shape of the cones, the cones are considered not to be formed by landslide or hotspot. The morphological characteristics are very similar to petit spot volcanoes near Japan Trench, northwestern Pacific Plate. More than one cluster are found out on the survey area, therefore there is a possibility that more small cones cluster exist on (northwestern) Pacific Plate.