To the east of the North Island the Pacific Plate is forced under the Indo-Australian Plate . The North Island of New Zealand has widespread back-arc volcanism as a result of this subduction . There are many large volcanoes with relatively frequent eruptions . There are also several very large calderas , with the most obvious forming Lake Taupo . Taupo has a history of incredibly powerful eruptions , with the Oruanui eruption approx. 26,500 years ago ejecting of material and causing the downward collapse of several hundred square kilometres to form the lake . The last eruption occurred and ejected at least 100 cubic kilometres of material , and has been correlated with red skies seen at the time in Rome and China . The associated geothermal energy from this volcanic area is used in numerous hydrothermal power plants . Some volcanic places are also famous tourist destinations , such as the Rotorua geysers
last eruption
Hatepe eruption
Geography of New Zealand