Report on Whakaari/White Island (New Zealand) — 1 January-7 January 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 January-7 January 2020
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2020. Report on Whakaari/White Island (New Zealand). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 1 January-7 January 2020. Smithsonian Institution and US Geological Survey.
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
On 6 January GeoNet reported that White Island remained in an elevated state of unrest. Very hot steam and gas emissions continued to rise from the 9 December vents, causing incandescence to be recorded on near infrared cameras. Volcanic tremor decreased to low levels on 14 December 2019 and remained low. Sulfur dioxide emission rates were at normal levels. Continuing movement of the back-crater wall W of the 1914 landslide deposits was detected and will continue to be monitored. Small amounts of ash sometimes rose from the active vent due to wall collapses, as on 23 and 26 December. The Volcanic Alert Level remained at 2 and the Aviation Color Code was lowered to Yellow.
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.