Government Information Service

The Volcanic Explanation
For The 24 Hour Period Ending 7 AM On Monday April 28, 1997
A Presentation Of The Government Information Services
In Conjunction With The MVO.

The current alert level is AMBER

The Volcanic Explanation is written by the Government Information Services in Montserrat at 8 am each morning of the week. It contains information from the Montserrat Volcano Observatory (MVO) up to 7 am the same morning. The explanation attempts to explain the activity at the volcano for the preceding 24 hours in a non technical nature. GIS attempts to put the explanation on line immediately it is completed, however sometimes it is difficult to get on line and therefore it is sometimes late being received. If (as sometimes happens) it is impossible to get on line within 24 hours of the publication of the explanation, the report is not sent and is incorporated into the next day's. Thank You!

The activity at the Soufriere Hills Volcano has been very quiet for the last 24 hours with occassional rockfall signals and pyroclastic flow signals being received at the seismic stations.

In addition there were quite a few long period earthquakes recorded by the stations, some of these led to rockfalls from the dome.

For most of the last 24 hours visibility of the dome has been very poor because of low cloud cover, however there was a brief period yesterday (Sunday) when there was some observation possible from the helicopter. The small pyroclastic flows of the weekend only travelled as far as the road to Galways Soufriere and it was also noted that the gully cut into the north of Galways Wall on April 24th has now been filled back in with debris.

The GPS survey of Saturday of the north of Montserrat showed no significant movement of the points measured, thus there is no deformation taking place.

Some ash samples were taken over the weekend from different spots and these will be sent to Britain for testing. It is estimated that about an eigth of an inch of ash was deposited in Plymouth during the last week. Everyone is urged to wear their dust masks when visiting ashy areas.

The alert level remains at AMBER which means that Zone A remains a "no go" area as the Tar River Valley and White River Valley are extremely dangerous. Zones B and C should only be visited in daylight hours for essential activities and anyone entering should have a rapid means of exit and remain vigilant and listen to ZJB Radio.

Government Information Service