An observation-gas flight confirms the active vents at White Islands volcano, New Zealand are continuing to emit a minor-moderate steam and gas plume, GeoNet reported on December 12, 2022. The Volcanic Alert Level (VAL) remains at 2.
On December 6, 2022, GNS Science volcanologists completed a gas and observation flight. They observed the normal minor-moderate gas and steam plume at the island, which is originating from several sources behind the crater lake, GeoNet’s Duty Volcanologist Cameron Asher noted.1
The observation-gas flight measured a low discharge rate of sulfur dioxide (SO2) of 273 ± 11 tonnes/day and 787± 178 tonnes/day of carbon dioxide (CO2). These outputs have not changed substantially from the October 14 levels.
“Our observations have confirmed a lowering of the lake level on the island,” Asher said.
“Our North Rim web camera remains obscured. Our previous Volcanic Activity Bulletin in October mentioned rare observations of ash emission from Whakaari. There have not been any observations that support continued ash emission or other eruptive activity.”
The VAL remains at Level 2 (moderate to heightened unrest) and the Aviation Color Code remains at Yellow, acknowledging the current level of activity, but also continuing to acknowledge the greater level of uncertainty in our interpretation due to the current lack of consistent, useful real-time data.
“As the weather allows, we will continue the frequent gas and observation flights over the island until we can service our on-island equipment and power supplies. We have access to webcam images from the island which are greatly obscured by wind-blown muddy ash, but still provide some level of visual monitoring between our flights.”
An impulsive, short-lived eruption occurred at the volcano at 01:11 UTC (14:11 LT) on December 9, 2019.
At the time of this sudden eruption in December 2019, there were 47 people visiting the volcano of which 22 died, either in the explosion or from injuries sustained. The bodies of two people were never found.
Geological summary
Uninhabited 2 x 2.4 km (1.2 x 1.5 miles) White Island, one of New Zealand’s most active volcanoes, is the emergent summit of a 16 x 18 km (10 x 11.2 miles) submarine volcano in the Bay of Plenty about 50 km (31 miles) 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 (3.1 miles) 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. The collapse of the crater wall in 1914 produced a debris avalanche that buried buildings and workers at a sulfur-mining project.2
1 Whakaari/White Island: Minor-moderate steam and gas emissions continue. Volcanic Alert Level remains at Level 2 – GeoNet – December 12, 2022
2 White Island – Geological summary – GVP
