Reporoa is a caldera. The only recent eruption was a phreatic explosion in about 1180 AD. The area of this eruption is now occupied by the Waiotapu thermal area, said to be one of the most beautiful in New Zealand.
Source of Information:
Simkin, T., and Siebert, L., 1994, Volcanoes of the World: Geoscience Press, Tucson, Arizona, 349 p.
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