Confirmation of submarine fumarole off Yamagawa Port in Kagoshima Bay and their search method

Submarine fumaroles, 'Tagiri' in Japanese, located in inner Kagoshima Bay (Japan) have been frequently observed by a training ship Nansei Maru. The basic searching method is to keep the ship over the submarine fumaroles by finding bubbles spouting from them when a sea surface is relatively calm, or by finding a certain vertical echo-sounding image of bubbles originated to submarine fumaroles when a sea surface is rough condition. Similar echo-sounding images to 'Tagiri' have been obtained off Yamagawa Port located at a mouth of Kagoshima Bay. Submarine fumarole located off Yamagawa Port had been searched by a ROV. The fumarole discharge sand, water and bubbles. Additional bubbles spouted from small vents in the area. The biological and sedimentary environments around fumarole are widely different from the 'Tagiri' area. The submarine fumarole discovered by this project is located at 31 degree -11'.912N, 130 degree -40'.333E (WGS) and the depth is 49.4m.