Government Information Service

The Volcanic Explanation
For The 24 Hour Period Ending 7 AM On Wednesday March 05, 1997
A Presentation Of The Government Information Services
In Conjunction With The MVO.

The current alert level is AMBER


The activity at the Soufriere Hills Volcano over the last 24 hours has been at a low level. The seismic station has recorded another earthquake swarm which lasted for most of yesterday morning (Tuesday). The swarm consisted of 22 volcano-tectonic earthquakes and 42 hybrid earthquakes which stopped early in the afternoon.

In addition there were about 20 rockfall signals which produced very small ash clouds. One of these early this morning (Weds) caused ash which drifted westwards over Plymouth.

Some EDM measurement was made yesterday. This consists of bouncing a beam of light off a reflector on the mountainside. Results show that the measured line between Upper Amersham and Lower Amersham shortened by 2.1 cms since February 19 and the line between Lower Amersham and Chances Peak steps has lengthened by 2.2 cms during the same period. These lines show that there is no long term deformation of this part of the volcano.

This morning there is little visibility of the dome because of low cloud cover, however scientists at the MVO are warning that the volcano is very active and dangerous. The lava dome is now larger than ever before with both its height and volume growing all the time. The extrusion rate is estimated at 4 cubic metres per second.

The dome has a very steep eastern face and it is expected that there will be pyroclastic flows in the near future down this face. Residents are therefore asked to remain vigilent and tune in to Radio Montserrat for updates.

Ash levels in the Plymouth area are described as hazardous and everyone is urged to wear their dust masks when in this area.

Government Information Service