Niuafoou is a volcano located on an underwater ridge west of the line along which all the other volcanoes of Tonga are ranged. The island contains a steep-sided
caldera; its rim is over high. It rises to a height of at Mokotu. The coastline is rocky and steep, with only a few beaches, all of which are stony, with
black sand. The only landing place on the island is at the end of a
lava flow in
Futu, in the western part of the island. All the villages are in the north and east. Public places — like the post office, telecommunications station and airport (
Kuini Lavinia Airport) — are in
Angahā in the north; there is a high school in
Mua. The island ring encloses two lakes. The larger one,
Vai Lahi, is a
crater lake above
sea level, wide, and deep. It contains three islands and a submerged island that appears when the water level drops. Vai Lahi is separated from the smaller lake, Vai Siʻi (or Vai Mataʻaho), by a desolate landscape of sand hills. The inner walls of the crater lake, and the island's eastern and western slopes, are forested. Either one or both are
soda lakes.
Volcanic activity The island is an active volcano, and has erupted regularly since 1814. In 1853, an eruption destroyed the village of ʻAhau and killed 25 people. An eruption beginning in August 1886 destroyed buildings and crops and created a new island in the lake. Another in 1912 involved thirty active cones and threw lava to a height of . In 1929, an eruption destroyed the village of Futu, cut off the harbor, and killed all the vegetation on the western slopes of the island. In December 1935, an eruption centered on the Ahofakatau and Hina craters caused the evacuation of Belani and Togamamao, and produced a lava flow. An eruption in September 1943 destroyed crops but caused no loss of life. A serious eruption began on 9 September 1946, beginning with a series of tremors and then a lava flow which destroyed the village of Angaha, including the government buildings and the wireless station. The village of Aleleuta was also destroyed, and lava flows had left only one third of the island still habitable. When radio contact was lost, an
RNZAF aircraft on a flight to
Samoa was requested to investigate, and reported the eruption to the outside world. The eruption was followed by a series of violent earthquakes. While the inhabitants initially planned to stay, in mid-October the Tongan government issued a compulsory evacuation order. An initial attempt to evacuate the island using the New Zealand vessel
Matua failed, as the ship arrived before the inhabitants were ready. The island was finally evacuated on December 21. The inhabitants were resettled in
Nukuʻalofa, where land had been provided by Queen Salote. In 1948 they were resettled in
ʻEua. When they resettled, they named various places in ʻEua after the places they had known in Niuafoʻou. As a result, the two islands now have many of the same place names, and a comparison of names on the two islands shows where each group of settled. In 1958, about half of the population returned to Niuafoʻou, and the rest remained in ʻEua.
Geology It is an
shield volcano, with a broad lava shield capped by the remnants of a composite cone, which was destroyed during a
caldera-forming eruption. The lavas contain variable amounts of
subduction-related components inherited from the
Tonga subduction zone to the east in the
tholeiitic magma series. == History ==