Shefa Province, Vanuatu
16.992 S, 168.592 E
summit elevation 521 m (Tongariki)
This unnamed caldera lies South of Tongoa. The exposed part of the rim is marked by the islands of Ewose, Buninga and Tongariki.
Little is known about this submerged caldera.
Eruptions may have occurred in the past 10,000 years.