Government Information Service

The Volcanic Explanation
For The 24 Hour Period Ending 6 PM On Saturday 30 November, 1996
A Presentation Of The Government Information Services
In Conjunction With The MVO


The activity at the Soufriere Hills Volcano increased over the last 24 hours. Since early this morning (Saturday) there has been a swarm of some 20 volcano-tectonic earthquakes, these VT's as they are better known as were all located at depths of less than two kilometres below the surface of the crater. They usually signify that magma is trying to reach the surface and fracturing rock in the process.

Other activity today includes 4 rockfall signals and one long period earthquake.

Scientists today have been monitoring the Galways Wall once again from the helicopter. Their inspections show that very little disintegration has occurred over the past 24 hours but the wall remains very unstable with severe fractures clearly visible. Further avalanches from the Galways Wall could happen at any time and a major collapse of this wall could expose hot, gas filled magma and trigger an explosion. This has the potential to damage a large area of St Patricks and surrounding areas in the south.

The October 1st dome is still growing and further rockfalls and pyroclastic flows are likely down the southeastern and northeastern sides. Steaming continues from a number of places on the dome most notably in the southern area close to Castle Peak.

Some electronic distance measurement (EDM), which entails bouncing a beam of light off a reflector on the side of the mountain, was carried out today. Results show a shortening of the lines to Castle Peak.

The MVO scientists today have been working with colleagues around the world to see what would happen if the Galways Wall were to collapse. The foremost expert in the world on crater rim walls, Dr Barry Voight of the U.S.A. will arrive in Montserrat on Monday to help with this work.

Government Information Service