Volcanic Alert Bulletin WI 2016/04
10:45 am Saturday 30 April 2016; White Island Volcano
Volcanic Alert Level remains Level 2
Aviation Colour Code remains Orange
Heightened volcanic unrest continues at White Island (Whakaari). During an aerial inspection on Friday the site of Wednesday’s eruption was seen for the first time; a new crater has formed in the north east corner of the 1978/90 Crater Complex. Gas output is slightly elevated but well within the range of recent measurements. Preliminary analysis of the eruption deposit suggests that no or little new magma (lava) was ejected. Seismic activity remains low. The Volcanic Alert Level remains at Level 2.
During an aerial inspection on Friday to measure the gas output and photograph the active crater area it was possible to confirm the location of the vent that erupted on Wednesday evening. A new crater has formed in the north-east corner of the 1978/90 Crater Complex. No vent was visible in this area before Wednesday. Significant collapse has occurred around the area and post-eruption landsliding is also present. Hot translucent gas has been emitted from the new vent.
The gas measurements confirm no significant change in the long-term gas output from the volcano. Volcano earthquake activity remains low.
Laboratory analysis of the eruption deposit collected from the web camera site on the north rim has confirmed that most of the ash is strongly hydrothermally altered old rock material. No evidence of new, juvenile magma was found. This suggests that no new lava material has been erupted and that the eruption was likely driven by steam and gas, like the eruptions in 2012 and 2013.
There is currently no indication that activity is either increasing or decreasing at White Island. The heightened state of volcanic unrest remains (Volcanic Alert Level 2). GNS Science volcanologists are continuing to monitor the volcano and further bulletins will be released as required.
April 30, 2016. White Island , New Zealand :
Source : Geonet ,Agnes Mazot