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 Supply Reef
Bathymetric map of Supply Reef Seamount courtesy of NOAA.

Quick Facts

Supply Reef is a conical submarine volcano in the northern Mariana Islands that rises to within 8 m of the sea surface. The andesitic seamount lies about 10 km NW of the Maug Islands, the emergent summit of a submarine volcano that is joined to Supply Reef by a low saddle at a depth of about 1800 m. Several submarine eruptions have been detected by sonar signals originating from points very approximately located at distances of 15-25 km NW of Supply Reef. From the Smithsonian Global Volcanism Program.
Latitude: 20.13° N
Longitude: 145.1° E
Elevation: -8 (m) -26 (f)
Volcano type: Submarine
Composition: Andesite
Most recent eruption: 1989 CE