Mayor Island Volcano - John Seach

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Bay of Plenty, New Zealand

37.28 S, 176.25 E
summit elevation 355 m
Shield volcano

Mayor Island is a peralkaline volcano of Quaternary age located 26 km north of Tauranga, Bay of Plenty, northeastern New Zealand. 

The island is 4.5 km wide and is characterised by a breached caldera 3 km wide with steep walls which rise up to 200 m above the caldera floor. The island lies in a back-arc setting of a convergent plate margin, 100 km behind the Taupo Volcanic Zone.

The volcano contains a 3 km wide breached composite caldera surrounded by
steep walls rising to 250-350 m above sea level.

No historical activity is known but hydrothermal activity consists of hot springs at Oira and Orongatea bays.

Over the past 135,000 years there have been 35 episodes of eruptions and two caldera collapses. The volcano is noted for its wide range of eruption types which include -  Hawaiian, Strombolian, Plinian, Phreatomagmatic, and lava domes.

The most recent eruptions may have occurred about 1000 years ago, produced a series of small crystal-rich lava domes and flows, confined to the “C” caldera floor.

Mayor Island Volcano Eruptions

~1000 AD, 4390 BC ± 200, 6050 BC ± 75