Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 31 August
to 16:00 01 September 1996

Activity at the Soufriere Hills volcano during this reporting period continued at about the same rate as during the previous 24 hours, with small- to moderate-sized rockfalls from the eastern flank of the lava dome dominating the activity.

Ninety two (92) rockfalls, 4 long-period, 21 hybrid and 107 volcano-tectonic earthquakes were recorded. Although rockfalls occurred throughout the reporting period, there was a period of near-continuous rockfall activity from 22:50 on 31 August to 02:00 on 01 September which was also probably associated with small pyroclastic flows in the Tar River valley. Most of these rockfalls and /or small pyroclastic flows were associated with small ash clouds which were blown on the wind towards the northeast, resulting in light ashfalls in the Long Ground, Whites, Trants, Bramble Airport and Harris' areas. The volcano-tectonic earthquakes occurred as two swarms from 20:06 to 22:40 on 31 August and 08:18 to 11:00 today. These VTs were located at shallow depths beneath English's Crater and are probably associated with the movement of magma from shallow depths to the surface as the process of dome growth at the Soufriere Hills volcano continues. Intermittent low-amplitude broadband tremor was also recorded at most of the stations closest to the Crater throughout the reporting period.

Although the volcano was covered by clouds during most of the day, there were brief periods when the clouds lifted and the dome could be seen clearly. Vigorous steaming was observed from several areas of the dome. The rockfalls and small pyroclastic were from the eastern flank but runoffs were generally not very long, i.e., most were less than about 1km.

COSPEC and EDM measurements were not attempted today.

Further rockfalls and pyroclastic flows will occur but all indications at the moment are that the pyroclastic flows will be confined to the Tar River Valley area. However, areas affected by associated ashfalls will obviously depend on the direction and strength of the wind at the time. People in areas affected by ash falls should exercise great care when driving. Dust masks should be worn in ashy environments.

The Tar River Valley and surrounding areas are now extremely hazardous, and should not be entered under any circumstances. We urge individuals who continue to ignore this advice to think very seriously before making trips to these highly hazardous zones.

A series of short-duration, seven-a-side, football matches were played today at Salem Park amongst four teams: the Montserrat Volcano Observatory, The Royal Montserrat Police Force, The Adventist Trendsetters and the Combined team. The Combined team emerged as champion after defeating Police. Unfortunately, the MVO lost all the three games it played but we will do better the next time.

Montserrat Volcano Observatory