Volcanoes
Auckland straddles the Auckland Volcanic Field, which has produced approximately 50 volcanoes. These take the form of cones, lakes, lagoons, islands and depressions, and several have produced extensive lava flows. Most of the cones have been partly or completely quarried away. The individual volcanoes are all considered extinct, although the volcanic field itself is merely dormant.
Unlike the explosive subduction-driven volcanism in the central North Island, such as at Mount Ruapehu and Lake Taupo, Auckland's volcanoes are fueled entirely by basaltic magma. The most recent and by far the largest volcano, Rangitoto Island, was formed within the last 1000 years, and its eruptions destroyed the Māori settlements on neighbouring Motutapu Island some 700 years ago. Rangitoto's size, its symmetry, its position guarding the entrance to Waitemata Harbour and its visibility from many parts of the Auckland region make it Auckland's most iconic natural feature. Few birds and insects inhabit the island because of the rich acidic soil and the type of flora growing out of the rocky soil.
Auckland straddles the Auckland Volcanic Field, which has produced approximately 50 volcanoes. These take the form of cones, lakes, lagoons, islands and depressions, and several have produced extensive lava flows. Most of the cones have been partly or completely quarried away. The individual volcanoes are all considered extinct, although the volcanic field itself is merely dormant.
Unlike the explosive subduction-driven volcanism in the central North Island, such as at Mount Ruapehu and Lake Taupo, Auckland's volcanoes are fueled entirely by basaltic magma. The most recent and by far the largest volcano, Rangitoto Island, was formed within the last 1000 years, and its eruptions destroyed the Māori settlements on neighbouring Motutapu Island some 700 years ago. Rangitoto's size, its symmetry, its position guarding the entrance to Waitemata Harbour and its visibility from many parts of the Auckland region make it Auckland's most iconic natural feature. Few birds and insects inhabit the island because of the rich acidic soil and the type of flora growing out of the rocky soil.
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