Report on White Island (New Zealand) — 22 January-28 January 2014
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 22 January-28 January 2014
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2014. Report on White Island (New Zealand). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 22 January-28 January 2014. Smithsonian Institution and US Geological Survey.
37.52°S, 177.18°E; summit elev. 321 m
All times are local (unless otherwise noted)
On 22 January, the GeoNet Data Centre reported that the Volcanic Alert Level for White Island remained at 1 and the Aviation Colour Code remained Green. Since a moderate eruption on 11 October 2013, seismicity had remained at low levels while gas flux was elevated. Sulfur dioxide flux ranged from 133 to 924 tonnes per day, higher than levels before 2012 when daily averages were less than 300 tonnes. The level of the water in Crater Lake continued to rise, and was about 5 m deeper than in late 2013. Temperature measurements with a recently acquired thermal Infrared camera confirm that hot gases were rising from vents on the lava dome; temperatures at the vents were 200-330 degrees Celsius, and over 400 degrees at one vent.
Geologic Background. Uninhabited 2 x 2.4 km White Island, one of New Zealand's most active volcanoes, is the 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 summit crater appears to be breached to the SE, because the shoreline corresponds to the level of several notches in the SE crater wall. Volckner Rocks, four sea stacks that are remnants of a lava dome, lie 5 km NNE. Intermittent moderate phreatomagmatic and strombolian eruptions have occurred throughout the short historical period beginning in 1826, but its activity also forms a prominent part of Maori legends. Formation of many new vents during the 19th and 20th centuries has produced 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.