Mayor Island

Country: New Zealand
Subregion Name: New Zealand
Volcano Number: 0401-021
Volcano Type: Shield volcano
Volcano Status: Radiocarbon
Last Known Eruption: 5060 BC ± 200 years
Summit Elevation: 355 m 1,165 feet
Latitude: 37.28°S 37°17'0"S
Longitude: 176.25°E 176°15'0"E

The small 4-km-wide Mayor Island, also known as Tuhua, in the Bay of Plenty is the emergent portion of a 15-km-wide compound peralkaline lava shield constructed between about 120,000 and 35,000 years ago. A 3-km-wide composite caldera was formed in two or three collapse events, the last of which took place about 6300 years ago, and was accompanied by a plinian eruption that produced tephra deposits up to 70 cm thick on mainland North Island. Post-caldera eruptions generated a series of lava domes and flows emplaced from NNE-trending vents within the caldera that have filled it to depths of at least 180 m. The latest eruption of Mayor Island has not been dated, but was considered by Houghton et al. (1992) to perhaps have occurred only 500-1000 years ago.

[link to www.volcano.si.edu]