Montserrat Volcano Observatory

Weekly Report
Report for the period 5 p.m. 11 June 1999
to 5 p.m. 18 June 1999

The level of activity at the volcano was at a lower level this week than over the previous reporting period.

A total of 120 rockfall signals and 29 volcano-tectonic earthquakes were recorded over the last week.

The main event of the week occurred on 17 June at 5:57 a.m. when pyroclastic flows were once again sourced from the area of the dome above Tuitt’s Ghaut. The main body of the flow travelled down the Tar River reaching the sea on the delta, and minor amounts of material were deposited in Tuitt’s Ghaut and White’s Ghaut. The ash cloud from this event travelled to the west and north-west, and light ash fall was deposited in Salem and Old Towne. This deposit contained a combination of very fine ash and small fragments of rock from the dome.

Correlation spectrometer measurements have continued this week. Values for the sulphur dioxide flux on 14, 15, 16 and 18 June were 230, 370, 170 and 400 tonnes per day respectively.

Residents of Montserrat are advised to keep listening to ZJB Radio Montserrat for information in case of any changes in the state of the volcano.

Montserrat Volcano Observatory