Rotoiti Caldera
Volcanic caldera in New Zealand / From Wikipedia, the free encyclopedia
The Rotoiti Caldera is a postulated,[1] mainly infilled sub caldera of the Ōkataina Caldera based upon gravitational and magnetic evidence.[2] While bathymetry of Lake Rotoiti is consistent with volcanic vents being present,[3] they could be in an area of collapse subsidence outside the north western margins of the Rotoiti Caldera itself.[2][lower-alpha 1]
Rotoiti Caldera | |
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Ōkataina Caldera, Okataina Caldera, Haroharo Caldera | |
![]() The gray centred outline is the postulated Rotoiti Caldera.
Ōkataina deposits in the years after the Rotoiti eruption with darker shading of violet for more recent. Clicking on the map enlarges it, and enables panning and mouseover of name/wikilink and ages before present. Key for the volcanics is: '"`UNIQ--templatestyles-00000004-QINU`"' basalt '"`UNIQ--templatestyles-00000005-QINU`"' dacite '"`UNIQ--templatestyles-00000006-QINU`"' rhyolite / ignimbrite '"`UNIQ--templatestyles-00000007-QINU`"'█ Definite vents. '"`UNIQ--templatestyles-00000008-QINU`"' Ōkataina Volcanic Centre with its embayments '"`UNIQ--templatestyles-00000009-QINU`"' postulated sub calderas of Cole et al. 2009 onwards | |
Highest point | |
Coordinates | 38°10′S 176°30′E |
Dimensions | |
Length | 15 km (9.3 mi) |
Width | 15 km (9.3 mi) |
Geography | |
Country | New Zealand |
Region | Bay of Plenty |
Geology | |
Age of rock | approximately 50,000 years |
Mountain type | Caldera |
Volcanic region | Taupō Volcanic Zone |
It erupted 100 cubic kilometres (24 cu mi) of magma[5] that is used in the recent stratigraphy of much of the northern North Island.[6][7][8][9][10] It was formed in the larger paired eruption with the lesser Earthquake Flat vents linked by tectonic interaction across the length of the Ōkataina Caldera.[11][5] The series of eruptions was about 50,000 years ago, with the resulting widespread Rotoiti ignimbrite and several layers of Rotoiti/Rotoehu tephra/brecca/ash giving challenges in consistent dating.[lower-alpha 2][12][13][14][15][16]: 188–90 It was subsequently infilled by later eruptive activity to a depth of over 2 km (1.2 mi).[2] The paired eruptions may have erupted about 240 cubic kilometres (58 cu mi) of tephra.[17]