Report on Whakaari/White Island (New Zealand) — 30 January-5 February 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 30 January-5 February 2013
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2013. Report on Whakaari/White Island (New Zealand). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 30 January-5 February 2013. Smithsonian Institution and US Geological Survey.
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
On 30 January GeoNet Data Centre reported that White Island's "hot lake" had dried up and a small tuff cone was forming on the former floor of the lake. The active vent continued to eject bursts of mud, rock, steam, and gas 50-100 m high. This activity along with the seismic activity was intermittent. Gas measurements taken during an overflight showed that the levels of volcanic gases emitted from the volcano were slightly higher than the levels measured the previous week: carbon dioxide gas flux increased from 1,800 to 2,000 tons/day, sulfur dioxide flux increased from 366 to 600 tons/day, and hydrogen sulfide flux was 19 tons/day (previously 15 tons/day). During 30-31 January seismicity changed to continuous tremor and remained at a high level. The Aviation Colour Code remained at Orange (second highest on a four-color scale) and the Volcanic Alert Level remained at 1 (on a scale of 0-5).
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.