Report on Whakaari/White Island (New Zealand) — March 1983
Scientific Event Alert Network Bulletin, vol. 8, no. 3 (March 1983)
Managing Editor: Lindsay McClelland.
Whakaari/White Island (New Zealand) No eruptive activity; B-type events increase
Please cite this report as:
Global Volcanism Program, 1983. Report on Whakaari/White Island (New Zealand) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 8:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198303-241040.
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
Aerial inspection by NZGS personnel on 10 March revealed no evidence of eruptive activity since 7 January. A white steam plume was rising to about 600 m altitude from the SE part of 1978 Crater. For 200 m to the N, there were moderate emissions from vents in deep gullies and from two fumaroles. Very little emission was originating from Donald Mound. Most of the Mound was covered with yellow sublimates, but a central zone was gray.
Since 7 January the number of low-frequency (B-type) events has increased, especially 9-15 February (more that 25/day; maximum, 42) and 22 February-4 March (more than 21/day). High-frequency (volcano-tectonic) events usually numbered fewer than 5/day, except for 6 on 29 January, 7 on 6 February, and 10 on 21 February. Wide-band seismic events were recorded on 19 and 24 February, and 2 and 6 March. They lasted 4-40 minutes with peak-to-peak amplitudes up to 70 mm.
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.
Information Contacts: B. Scott, NZGS, Rotorua.