Report on Whakaari/White Island (New Zealand) — 8 August-14 August 2012
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 8 August-14 August 2012
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Whakaari/White Island (New Zealand). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 8 August-14 August 2012. Smithsonian Institution and US Geological Survey.
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
The GeoNet Data Centre reported that scientists visited White Island on 9 August and observed an ash plume rising as high as 300 m from a new vent in the SW corner of the 1978/1990 Crater Complex. Black ash was depositing on the wall of the Main Crater to the W of the vent. The vent had started to build a tuff cone and there were impact craters around it created by ejecta from explosions. There was no sign of impact craters or blocks outside of the 1978/1990 Crater area. During 9-14 August volcanic tremor remained at low levels and a weak ash-and-steam plume rose a few hundred meters from the vent. The plume color changed between white and gray as the ash content varied. On 13 August the Alert Level remained at 2 (on a scale of 0-5), and the Aviation Colour Code was lowered to Yellow (second lowest on a four-color scale).
Geologic Background. The uninhabited Whakaari/White Island is the 2 x 2.4 km emergent summit of a 16 x 18 km submarine volcano in the Bay of Plenty about 50 km offshore of North Island. The island consists of two overlapping andesitic-to-dacitic stratovolcanoes. The SE side of the crater is open at sea level, with the recent activity centered about 1 km from the shore close to the rear crater wall. Volckner Rocks, sea stacks that are remnants of a lava dome, lie 5 km NW. Descriptions of volcanism since 1826 have included intermittent moderate phreatic, phreatomagmatic, and Strombolian eruptions; activity there also forms a prominent part of Maori legends. The formation of many new vents during the 19th and 20th centuries caused rapid changes in crater floor topography. Collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project. Explosive activity in December 2019 took place while tourists were present, resulting in many fatalities. The official government name Whakaari/White Island is a combination of the full Maori name of Te Puia o Whakaari ("The Dramatic Volcano") and White Island (referencing the constant steam plume) given by Captain James Cook in 1769.