Montserrat Volcano Observatory


Morning Report
Report for the period 16:00 4 January
to 07:00 5 January 1997
The current alert level is ORANGE


Rockfall activity continued overnight and is still at a relatively high level. The peak in rockfall activity occurred between 7 and 10 pm yesterday evening. There have been very few volcano-tectonic earthquakes overnight, suggesting that the short-lived swarms reported yesterday have died out again. A period of continuous tremor on all stations was recorded for about 1.5 hours after midnight this morning, possibly indicating a return to the pattern of banded tremor seen several times over the past 3 weeks.

Visibility is poor this morning, with the crater area covered by clouds.

The high level of rockfall activity suggests that the lava dome within English's Crater is growing rapidly, and a collapse of part of the dome may occur soon, producing pyroclastic flows and ash. Should the collapse be very large, then an explosive eruption is possible, in the same way that it followed a major dome collapse on September 17/18. All residents of Montserrat are reminded of the potential hazards from the volcano during dome collapses and explosive eruptions, which include pyroclastic flows, falling rocks and ash. MVO scientists cannot predict how large any particular collapse is going to be but will be able to tell when one is under way. That and all other information relating to the current activity will be passed to the authorities and the public immediately, and everyone is asked to stay alert over the next few days.


Montserrat Volcano Observatory