Report on Whakaari/White Island (New Zealand) — 19 February-25 February 2020
Smithsonian / US Geological Survey Weekly Volcanic Activity Report,
19 February-25 February 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, 19 February-25 February 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 19 February GeoNet reported that White island remained at an elevated state of unrest, confirmed by two overflights of the island for visual observations and data collection. Results from a gas data showed a steady decline on both carbon dioxide and sulfur dioxide flux, though levels were still slightly elevated. Thermal infrared data indicated that the fumarolic gases and the five lobes of lava in the main vent remained very hot at 660 degrees Celsius. A small pond of water had formed in the vent area and small-scale jetting was occurring, similar to September-December 2019 activity. The Volcanic Alert Level remained at 2 and the Aviation Color Code remained at Yellow.
Geological Summary. 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.