Montserrat Volcano Observatory

Morning Report
Special Report 07:00 28 November 1996
The alert level was upgraded from AMBER to ORANGE early this morning.

The situation at the volcano is extremely serious, and could escalate further during the next few hours. A major collapse of the Galways Wall, part of the southern crater wall, could expose hot, gas-rich magma from low down in the dome, and cause a lateral blast to the south of the volcano. There would be very little or no warning of this event.

There was an increase in the level of activity at the Soufriere Hills Volcano early this morning. Between 01:39 am and 03:00 am, an intense and continuous seismic signal was recorded at all stations in the network. This signal was caused by debris flows in the Whites river and both pyroclastic flows and debris flows in the Tar River valley. The debris flows were associated with heavy rainfall. Further activity occurred between 5 am and 6 am, although this was of lower intensity that the firstperiod.

A helicopter inspection of the volcano was carried out at first light. Material from the base of the Galways Wall has been washed down the Whites river to the sea, where a small delta has built up. The Galways Wall itself remains in about the same condition as yesterday, although the uppermost part of the wall was not visible due to low cloud. It is still unstable, and further collapses could occur at any time. There has also been some debris flow activity in the Tar River valley, where erosion of the pyroclastic flow deposits has exposed some hot material, leading to vigorous steam venting. New pyroclastic flow deposits were observed extending to about one km from the foot of the October 1st dome. A small pyroclastic flow also occurred at 06:00 am.

A total of 16 VT earthquakes were recorded by the seismic networks overnight, indicating that the VT swarm is still continuing. Rockfall activity from the October 1 dome has increased since 11 pm last night, although most of the rockfalls were small.

The scientific team stress that the situation at the volcano is extremely serious this morning, and could escalate with little notice. Residents of Montserrat should follow the advice given on Radio Montserrat. In particular, zones A and B are very dangerous and should not be entered under any circumstances.

Montserrat Volcano Observatory