Weekly Report 19 – 26 May 2017

Activity at the Soufrière Hills Volcano remains low.

The seismic network recorded four volcano-tectonic earthquakes this week.

Several measurements of the SO2 flux were made on 16, 18 and 19 May with the help of a team from the University of Manchester and INGV, Italy. The measurements were made using an ultra-violet spectrometer traversing beneath the gas plume in either the helicopter or a vehicle. A total of 30 traverses were carried out over the three days, giving an average SO2 flux of 232 tonnes/day. This is a provisional result and the data, along with other gas data collected at the same time, is still being analysed. However, it is felt that this estimate is more accurate than the lower values reported in November 2016 and January 2017.

Pyroclastic flows can occur at any time without warning on any side of the volcano, including Gages from where they can travel rapidly into Plymouth. Tracks across the Belham Valley can be destroyed or heavily modified by flash flooding or lahars, and caution should be exercised crossing the valley during and after rainfall.

The Hazard Level is 1. There is no public access to Zone V, including Plymouth. Maritime Zones E and W are daytime transit only between sunrise and sunset (boats may sail through the zone but must not stop). Anyone who ignores these restrictions is liable to be prosecuted.

This report along with additional information on the Soufrière Hills Volcano and the Hazard Level System can be found at the MVO website: www.mvo.ms. You can also follow @mvoms on both Facebook and Twitter.