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Vanuatu Volcano Alert Bulletin n°8 - Ambae Activity (August 31st 2022)

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

The volcanic activity on Ambae Island is continuing in the major unrest state. The Volcanic Alert Level remains at Level 2.

The volcanic activity on Ambae is continuing in the major unrest state, with a lower level of activity, consistent with the Volcanic Alert Level 2. The Ambae Volcanic Alert Level was in Level 2 since 14th December 2021. New analysis suggest that the volcanic activity is likely to pursue in this lower level of activity of major unrest state but could increase to a high level of activity of major unrest state. Volcanic hazards remain at the summit area and creeks (e.g., remobilization of remaining ash from 2017 and 2018 eruption and current activity)..

The danger zone for life safety at the summit area remains limited in the Danger Zone A (See Ambae caldera safety map below). This danger zone (Danger Zone A) is about 2 km radius from the 2017-2018 active vents. An additional danger zone is within areas of flowing creeks during heavy rain.

Latest seismic and observation data from the monitoring system confirmed the ongoing volcanic activity and the cone built up (at end December 2021) inside Lake Voui remains. The volcano continues to emit volcanic gas and possible ashes that is quasi contained within Lake Vui. These observations of the current activity is consistent with the activity of the Ambae volcano under Volcanic Alert Level 2 indicating ‘Major level of unrest; the Danger area remains at 2 km around the volcanic vents and within the area of flowing creeks. With this current volcanic activity, it is a useful reminder that eruptions can occur at any level of unrest with little or no warnings.
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 that crater is now filled by Lake Voui; however, the modern active vent area is now within the volcanic cone that grew in 2017-2018. 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 2017-2018 eruption episode started in 1991, with eruptions in 1995, 2005, and 2016 leading to the 2017-2018 activity.

All tourism agencies, local authorities, people of Ambae and the general public are advised that with the current volcano activity, the danger zone (Danger Zone A) remains at the summit about 2 km radius from the 2017-2018 active vent. In addition, the presence of remaining volcanic ashes elsewhere in the island (deposited during the 2017/18 eruption), can be mobilized by rainfall. The villages located near flowing creeks (dangerous flow zones) can continually expect changes in stream behavior and larger than normal flow rates during heavy rain fall. People of Ambae Island need to be aware of the dangerous water flows while approaching these creeks during heavy rains.
More information about the volcanic hazards can be found on the website:
https://www.vmgd.gov.vu/vmgd/index.php/geohazards/volcano/volcano-info/resources

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

Note : « Posted sign » : Signs will be installed later at the locations shown on the above image.

For further information, please contact Geohazards Division at the Vanuatu Meteorology and Geohazards Department at geohazards@meteo.gov.vu or 24686.