Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 10 June
to 16:00 11 June 1996

Activity at the Soufriere Hills volcano continued at a moderate level over the period under review. The activity, which is now mainly concentrated on the north and north-west section of the dome, is still dominated by small to moderate-sized rockfalls.

Small to moderate rockfall signals continue to dominate seismicity at the volcano. There were 87 of these events during this reporting period. The largest rockfalls occurred at 18:23 on 10 June and 12:53 and 15:40 on June 11. There were five hybrid events and 12 long period earthquakes. All of these seismicity counts are at slightly higher levels than over the past few days. A regional earthquake of magnitude 5.2, located 95 miles south-south-east of the Dominican Republic was also recorded on the local network. There have been brief periods of intermittent low-amplitude broadband tremor throughout the reporting period.

Observations of the dome were made under variable viewing conditions from the helicopter this afternoon. The moat area behind the Gages Wall was completely filled to the rim with debris and some larger blocks were seen in upper Fort Ghaut. Some activity were also seen on the north-eastern side of the dome. The top and southern sections of the dome were obscured by passing clouds.

EDM measurements were made today on the eastern triangle. No further change to yesterdays movement of 5 millimetres was detected at the Castle Peak reflector today.

COSPEC measurements of the SO2 gas concentration in the volcanic plume were not carried out today. The measurements for yesterday's traverses ranged between 40 and 69 tonnes per day, a lowering of levels from the past few days.

Scientists at the Montserrat Volcano Observatory remain very concerned about the current state of the volcano and the dangers to people and property on both the eastern and upper western flanks of the volcano. Visits to the evacuated zone should be kept to an absolute minimum. The Tar River, Long Ground and Whites areas remain extremely dangerous. The upper Fort Ghaut and Gages Village areas are now also extremely dangerous and the road between Lee's Estate and Ryners Village has been closed. People should not enter these areas under any circumstances. If they do, they put themselves at direct risk of serious injury or hideous death.

Montserrat Volcano Observatory