Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 02 May
to 16:00 03 May 1996

Activity at the Soufriere Hills volcano during this period has continued at roughly the same level observed during the previous 24 hours. Rockfalls and associated ash clouds continue to be produced.

Seismic activity changed during the reporting period. The low-amplitude broadband tremor that has dominated the seismicity over the last few days changed in character at around 17:00 on 02 May, from near-continuous to intermittent. The small hybrid earthquakes reappeared at about the same time, then gradually increased in number, from one every two or three minutes at the start to about one every minute by the end. The size of these events also increased. There was a further period of near-continuous tremor from 14:30 until 16:00 on 03 May. Several rockfalls were recorded throughout the reporting period, none of them very large. The small long period earthquakes that have been recorded recently declined to zero during the 24 hours. One small VT earthquake was recorded at 15:38, but could not be located.

The eastern EDM triangle was measured today. The results continue to show only very small changes, consistent with slow deformation of the volcanic edifice. The GPS receiver was deployed for an extended period at Farrell's lookout in order to obtain an accurate position for that benchmark. The height of the top of the dome was measured at 2,983 ft, an increase of 36 ft since yesterday.

Further COSPEC measurements were made today but the data is still being processed.

Visibility was poor for much of the day, but observations were possible at times in the morning and afternoon. Rockfall activity was concentrated mainly in the northern and northeastern sectors of the dome. Most of these were associated with ash clouds which were blown on the wind towards the west, resulting in the deposition of very small amounts of ash in the Upper Gages and Amersham areas. The dome continues to grow. Steve Sparks leaves the island today. During his visit he has established a programme to map the lava dome and contributed much to the interpretation of the current situation.

The MVO still views the situation at the Soufriere Hills Volcano with grave concern and the scientists continue to urge that visits to the evacuated zone be kept to a minimum. The Tar River, Long Ground and Whites areas are extremely dangerous and should not be entered under any circumstances.

Montserrat Volcano Observatory