Reporoa Caldera

Reporoa Caldera
Highest point
Elevation592 m (1,942 ft)
Coordinates38°25′00″S 176°20′00″E / 38.41667°S 176.33333°E / -38.41667; 176.33333
Dimensions
Length15 km (9.3 mi)
Width10 km (6.2 mi)
Geography
LocationTaupō Volcanic Zone, New Zealand
Geology
Rock age
Mountain typeCaldera
Last eruption1180 (?), 2005 hydrothermal

The Reporoa Caldera is a 10 km by 15 km caldera in New Zealand's Taupō Volcanic Zone located in the Taupō-Reporoa Basin. It formed some 280,000 years ago,:197 in a large eruption that deposited approximately 100 km3 of tephra, forming the Kaingaroa Ignimbrite layer. The ignimbrite sheet extends up to 15 km (9.3 mi) to the east.

In April 2005, a large hydrothermal explosion occurred near a cow paddock within the Taupō-Reporoa Basin, destroying some trees, temporarily blocking a nearby stream and creating a 50-metre crater at 38°32′02″S 176°10′19″E / 38.533832°S 176.172010°E / -38.533832; 176.172010. A similar explosion happened in the area in 1948, and smaller explosions have happened in the years between. At the time of the last eruption, it was believed to be within the caldera, but these recent eruptions are not technically within the now known area of the caldera.:197