Montserrat Volcano Observatory


Daily Report
Report for the period 16:00 11 October
to 16:00 12 October 1996
The current alert level is AMBER


Some views of the October 1 dome have been obtained today, and it seems to be about the same height as yesterday. Several rockfalls were observed, indicating that dome growth continues. Seismic activity remains low.

Six small rockfall events were recorded by the seismic network today. There have been no other seismic events, apart from some moderate tremor that was recorded on the Gages station from 0120 to 1200 today. This tremor was stronger than any recorded recently, but was only seen at the Gages station. The cause of this tremor is a bit of a mystery, but it is thought to be due to movement of water and steam within the volcano.

Visibility was poor for most of the day, but some views of the October 1 dome were obtained from Whites this morning. Regular small rockfalls were observed from the east face of the dome. The dome does not appear to have grown since yesterday, but it is possible that current dome growth is concentrated on the western side of the new dome, which cannot be seen in cloudy conditions.

GPS measurements were made on the network which straddles the volcano. The work is still continuing, but should be completed soon, and the results will be available in a couple of days. The network was last measured just after the 17/18 September explosion.

The installation of the new network of seismometers is nearly complete, although some problems with transferring data from the stations in the east to the Observatory by telephone have still to be resolved.

The eastern face of the October 1 dome is quite steep, and large rockfalls and possibly pyroclastic flows may occur during the next few days. The volcano remains highly active, and pyroclastic flows could trigger another explosive eruption with very little warning. Everyone who enters the evacuated zone must remain alert and be ready to move at short notice. Individuals who go beyond the Long Ground area into the Tar River valley are risking death. All residents of Montserrat are urged to become familiar with the new alert system and evacuation procedures.


Montserrat Volcano Observatory