Vanuatu Volcano Alert Bulletin n°5 - Vanua Lava Activity (7 June 2018)

from Government of Vanuatu
Published on 07 Jun 2018 View Original


Thursday June 7th 2018

15°24’0”S 167°50’0”E Summit 4908ft (1496m)
Current Vanuatu Volcano Alert Level:** Level 2**

**Ambae volcano is in the major unrest state. The Volcanic Alert Level is lowered to Level 2 **.

Ambae volcano activity becomes stable. The current volcanic activity is consistent with Volcanic Alert Level 2. The Danger Zone for life safety is now limited at 2 km radius from the active vent and areas located in the Yellow Zone (See Map below).

Observations in May 2018 confirm that the eruptive activity occurred in March until April has dropped. There is no explosions and volcanic cloud emitted are white color, means only steam. A small scale eruption in Lake Voui has ceased.

The presence of ash that has fallen on Ambae during the last eruption will continue to change the behavior of streams and creeks when it rains. The creeks and streams can produce floods and carry a lot more debris (sands, gravel and boulders). The flow path of streams and creeks could change due to the flood debris. Landslide may occur at some areas during heavy rain fall.

These observations and the analysis of seismic data confirm that the volcano activity is in the major unrest state. The volcano activity consist of ongoing emission of steam and/or volcanic gases. The local population and visitors can smell the volcanic gas while approaching the volcano.

Significant impact of ashes and gases emission to villages at Ambae started in March, when the Volcanic Alert level was raised to Level 3. Observations of the current activity are consistent with the Alert Level 2 activity. Level 2 indicates _‘Major unrest; Danger is now at 2 km around the volcanic vents and areas inside the Yellow Zone’ _. **The possibility that the Ambae volcano activity escalate to the level of minor eruption is moderate to low **.

Ambae volcano is a very large volcano and is frequently active. A large-scale eruption about 400 years ago built a volcanic cone in the summit crater and the crater is now filled by Lake Voui; the modern active vent area underlies Lake Voui. Historic activity is poorly known, but there is documented activity in 1530, 1670, 1870, 1915 and 1966. All documented activity has been from the summit crater (Lake Voui) except for the 1670 activity, which included a flank eruption producing lava flows at Ndui Ndui. The current eruption episode started in 1991, with eruptions in 1995, 2005, 2016 and 2017. The current eruption is focused in the summit crater and there are no indications of activity elsewhere on Ambae Island for now.

Advise to all tourism agencies, local authorities, people of Ambae and the general public **not to access the Danger Zone which is now about 2 km radius from the eruptive vents. Volcanic gases are expected in this area. Villages in the Yellow Color may continue to expect change in streams and creeks flows during rain fall **(See map below). Villages from Ambae island may experience impacts of volcanic gases especially those exposed to prevailing trade winds direction. (Please see the Volcano key Messages at the link below):

The Vanuatu Meteorology and Geohazards Department will continue to closely monitor this volcano activity. More information will be provided as available.

_For further information, please contact Geohazards Division at the Vanuatu Meteorology and Geohazards Department at or 24686 _.