Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 03 March
to 16:00 04 March 1997
The current alert level is AMBER

Activity at the volcano has continued at a low level for the last 24 hours although another earthquake swarm was recorded. Only the lower flank of the dome was visible for most of the day and no good views were obtained of the summit area.

An earthquake swarm consisting of volcano-tectonic and hybrid events occurred between 4:53 am and 1:40 pm today. The swarm was less intense than the last one recorded two days ago and consisted of 22 volcano-tectonic and 42 hybrid earthquakes. Most of these events occurred during the swarm. Eighteen rockfalls were recorded, the largest of which produced very small ash clouds which did not extend further than the summit area. No long period events were recorded.

EDM measurements were conducted on radial lines between upper and lower Amersham and between lower Amersham and Chances Peak steps. The line length between upper and lower Amersham shortened by 2.1 cm since the last measurements were made on 19 February. In contrast, line lengths between lower Amersham and Chances Peak steps lengthened by 2.2 cm during the same period. These lines continue to show no long term trends which indicate deformation of this part of the volcano.

No COSPEC measurements were made today.

A long occupation of a GPS line between the Farrells crater wall and Harris Lookout was conducted during the past 24 hours. Such long occupations increase the accuracy of the measurements and gives a better fix on station locations.

The volcano remains active and potentially dangerous. The dome is currently larger than ever before, and shows signs of becoming more active. The situation could worsen over a period of a few hours, and so it is dangerous to spend the night in the evacuated areas. People entering Zone C are reminded to remain alert at all times, and spend the minimum possible time in the evacuated zone. Residents should be reminded that at this current level of alert persons should not be permanently residing in Zones A, B or C. The ash levels in Plymouth can be hazardous, and so it is essential to wear a mask when there is ash in the air. The Tar River Valley and the upper Galway's area are very dangerous and should not be entered at any time.

Montserrat Volcano Observatory