Government Information Service

The Volcanic Explanation
For The 24 Hour Period Ending 6 PM On Sunday December 22, 1996
A Presentation Of The Government Information Services
In Conjunction With The MVO.

Activity at the Soufriere Hills Volcano shows renewed growth of the October 1st dome (dome # 2) which could cause pyroclastic flows in the Tar River Valley area. In addition there is still serious deformation of Galways Wall which could collapse with little or no notice.

The new infra red equipment was used during last night and it showed that the October 1st dome is very active in a number of places around the dome. Quite a few ashclouds were generated during the course of today (Sunday) and some of the ash dropped in Plymouth.

Helicopter inspections during the day confirmed this renewed activity at the October 1st dome and in addition a number of rockfalls have occurred at the Galways Wall recently.

During today there were only a few volcano-tectonic earthquakes recorded but there were sixteen long period earthquakes. Repetitive hybrid earthquakes were recorded throughout the day and activity at this level has not been seen since last April this is probably an indication of dome growth.

Some EDM measurements were made today on the Castle Peak lines they showed a shortening of about 6 centimetres which is a high rate of deformation, however these types of changes have been seen in the past.

At the MVO today, Dr Willie Aspinall left for England and Dr Simon Young resumes the role of chief scientist until January when Lloyd Lynch returns from the Seismic Research Unit.

Government Information Service