Hunga Haʻapai

Hunga Tonga–Hunga Ha'apai is a submarine volcano in the South Pacific located about 30 km south of the submarine volcano of Fonuafoʻou and 65 km north of Tongatapu, Tonga's main island. It is part of the highly active Kermadec-Tonga subduction zone and its associated volcanic arc, which extends from New Zealand north-northeast to Fiji, and is formed by the subduction of the Pacific Plate under the Indo-Australian Plate. It lies about 100 km above a very active seismic zone.The volcano rises around 2,000 m from the seafloor and has a caldera which – on the eve of the 2022 eruption – was roughly 150 m below sea level and 4 km at its widest extent.