Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 01 March
to 16:00 02 March 1997
The current alert level is AMBER

Activity at the volcano has continued at about the same level during the last 24 hours, with another earthquake swarm being recorded. Some reasonable views of the dome today allowed observation of continued growth of the January dome, and a view of the dome last night showed that, in addition to the active area on the south-eastern flank of the January dome, some small areas of the October dome were glowing red.

The swarm of earthquakes that started yesterday morning at 1.56 am ended at 6.19 pm yesterday evening. A second swarm of volcano-tectonic and hybrid earthquakes began at 11:30 pm last night and continued until 11:00 am this morning. A total of 27 volcano-tectonic earthquakes and 109 hybrid events were recorded during this reporting period, most of these occurring during the swarms. Thirteen rockfall signals were recorded during the reporting period. Most of these produced only small ash clouds which drifted to the west of the volcano depositing ash on Chances Peak and surrounding areas. There were no long period events, and no periods of tremor were recorded.

A view of the dome from Whites last night revealed three red hot chutes in the south-east face of the January dome. In addition there was a possible line of weakness visible in the October dome defined by a shallow, southerly dipping line of red hot fumaroles on its northern face. Reasonable visibility of the dome from the airport in the morning allowed some views to be obtained. It was thought that the height of the dome had increased since yesterday's observations, although no measurements were made. Later in the day attempts were made to view the dome from the helicopter but visibility had deteriorated markedly, and no good views were achieved.

COSPEC measurements were made on 6 traverses along the western side of the volcano this afternoon and results are currently being processed. Results from yesterday's runs show an average flux of sulphur dioxide of 165 tonnes/day. The weekly rainwater and ash samples were collected from sites to the west of the volcano today.

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