Global Volcanism Program | Image GVP-12160
Sidescan Sonar imagery taken in 2003 shows South Sarigan seamount, rising to within about 184 meters of the sea surface 12 km south of Sarigan Island. It was the site of a short-term explosive submarine eruption in May 2010 that produced a plume of ash and steam to 12 km altitude. South Sarigan seamount shows an irregular summit with multiple peaks, including a possibly young cone at about 350 m depth, and flank morphology suggests it is a frequently active volcano.
Map courtesy Bill Embley and William Chadwick (NOAA: http://oceanexplorer.noaa.gov/explorations/03fire/logs/feb17/feb17.html)