Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 19 October
to 16:00 20 October 1996
The current alert level is AMBER

The level of activity at the volcano has been slightly lower today, although a rockfall at 1135 was the largest recorded since the explosion.

There were only five volcano-tectonic earthquakes, a decrease compared to previous days. Most of these events occurred between 2345 last night and 0145 this morning. The VTs were located at depths of less than 2 km beneath the crater. Eleven rockfall signals were recorded, and two of these had sharp, long-period starts that are associated with small explosions.

The most significant event today was a large rockfall at 11:35. This rockfall was heard by scientists at Harris's and on Perches Mountain, although no ash cloud could be seen because of low cloud. Viewing conditions have been good at times, but no clear views of the October 1 dome were obtained.

No COSPEC measurements were possible due to unfavourable weather conditions.

A GPS survey was conducted on the network that spans the north of the island. The results are currently being processed. The preliminary results from the survey of the network around the volcano carried out last weekend show no major changes since the last time the network was measured in September.

Aerial photographs of the fan at the bottom Tar River valley were taken from the helicopter this afternoon. These will allow more accurate mapping of the current fan area.

The volcano remains in an active and highly dangerous state. Further activity, possibly leading to an explosive event could occur with little warning in the near future. 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.

Montserrat Volcano Observatory