Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 31 October
to 16:00 01 November 1996
The current alert level is AMBER

Activity at the volcano has been at a higher level today due to an intense VT earthquake swarm, although few rockfalls or other seismic signals were recorded. Visibility was very poor most of the day and the summit of the volcano was obscured by low cloud until late this afternoon.

Sixty six volcano-tectonic earthquakes occurred during the period, all of which occurred in a swarm which started at 00:27 on 1 November and was continuing at the end of the reporting period. These events were all located at shallow depth beneath the crater. Their amplitude is somewhat variable but generally higher than other similar events over the past week or so. Six rockfall signals occurred during the period, and five long-period events were also recorded. One regional event located about 35 km north of Montserrat was recorded at 02:17 on 01 November.

The viewing conditions were very poor for most of the day. However, some views into the crater were obtained from the helicopter late in the afternoon. The central summit area of the 1 October dome has increased in elevation, and has at least one stubby spine on it. Deposits from rockfalls and small pyroclastic flows extend to about the level of the Tar River Soufriere within the canyon, considerably further than two days ago. This information suggests that the dome is still growing at a similar rate to the past month.

An EDM survey was completed on the radial lines from Amersham to Dagenham, Upper Amersham and Chances Peak Steps during today; the results show that the Lower to Upper Amersham line continues to be erratic whilst the others show trends indicating the target sites are stable.

No COSPEC measurements were made today due to inclement weather conditions.

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