Sangihe Islands (Indonesia)
The Banua Wuhu submarine volcano in the Sangihe Islands rises more than 400 meters from the sea floor to form a shoal less than 5 meters below sea level. Banua Wuhu is an active submarine volcano. It is a parasitic element on the north western side of adjacent Mahenetang Island. Banua Wuhu is an intermittently emergent pustule of known volcanic and shallow hydrothermal activity. Gas bubbling, sub-surface sonic activity and venting of hydrothermal liquefied with temperatures around 50°C are known to occur on the zenith at around 10meters depth. A 90 meters high island was formed in 1835, but then dwindled to only a few rocks in 1848.