Government Information Service

The Volcanic Explanation
For The 24 Hour Period Ending 7 AM On Monday January 27, 1997
A Presentation Of The Government Information Services
In Conjunction With The MVO.

Once again the level of volcanic activity at the Soufriere Hill Volcano has remained at a low level for the last 24 hours.

The seismic activity has been dominated by three swarms of volcano - tectonic earthquakes (VT's) and some rockfall signals. The VT's usually indicate that magma is trying to reach the surface from low level depths below the volcano's crater. The last of the VT swarms ended very early this morning (Monday).

There were good views of the dome yesterday and it was observed that further growth has occurred in the last few days. The scar left by the January 20th collapse of the dome is now filling back in. There is a new extrusion visible and it has reached the height of the scar rim and is composed of large blocks.

There have been further landslides from Galways Wall area and new cracks have appeared in it. In addition on Sunday scientists went via helicopter to the top of Chances Peak to measure the width of the two large cracks across the crater rim between Chances Peak and Galways Wall, one of the cracks has opened by a further 7 cms during the last few days which is a significant increse. Scientists will continue to monitor this area very carefully over the next few days and weeks.

Some EDM measurements were taken on Sunday from O'Garro's to the reflector on Chances Peak, the line has shortened by about 4 mm since the last measurement in December.

The visibility this morning is poor because of low cloud cover however there seems to be high level of steam emmission from the vicinity of the base of Castle Peak and the upper north eastern section of the dome.

The alert level remains at ORANGE, and the W.H. Bramble Airport is open as normal. The Tar River Valley and Long Ground areas are very dangerous and should be kept well clear of.

Government Information Service