Report on Whakaari/White Island (New Zealand) — January 1988
Scientific Event Alert Network Bulletin, vol. 13, no. 1 (January 1988)
Managing Editor: Lindsay McClelland.
Whakaari/White Island (New Zealand) Seismicity increases; tephra columns
Please cite this report as:
Global Volcanism Program, 1988. Report on Whakaari/White Island (New Zealand) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 13:1. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198801-241040
37.52°S, 177.18°E; summit elev. 294 m
All times are local (unless otherwise noted)
Eruptive activity from vents within 1978 Crater continued through January. In early December a marked increase in the number of A-type (high-frequency volcano-tectonic) earthquakes occurred, with events frequently numbering more than 5/day. The magnitude of larger events was ~2.5. E-type explosion/eruption earthquakes were recorded most days; amplitudes ranged from 20 to 200 mm. Eruption columns associated with 3 of the events were reported (table 6).
|Date||Time||Description of Activity|
|02 Dec 1987||0257||Roar heard by observers on boat in Crater Bay.|
|02 Dec 1987||0626||600-900-m-high eruption column observed and photographed from Crater Bay, White Island.|
|27 Dec 1987||1823||900-1,500-m-high eruption column observed from Pukehina (65 km SW).|
|31 Dec 1987||1439||Tall eruption column reported by several observers on Bay of Plenty coast.|
During a 14 January visit, ash emissions from both Hitchhiker vent (in Congress Crater, on the E side of 1978 Crater) and the November 1987 vent (on the W edge of the 1978 Crater floor) were observed. Enlargement had occurred at both vents since the November 1987 visit; the new vent was estimated at 10-15 m in diameter. The proportion of non-altered andesitic material in the tephra increased, but no magmatic material was recognized.
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.
Information Contacts: B. Scott, NZGS Rotorua.