Montserrat Volcano Observatory


Daily Report
Report for the period 6 pm 19 November
to 6 pm 20 November 1997


Seismicity today has continued to be dominated by rockfall signals, although there have also been a lot of very low amplitude hybrid earthquakes. Early this afternoon there was an episode of vigorous ash venting that caused a plume of ash to reach 3000 feet high.

Between 16:00 yesterday and 16:00 today there were 20 long-period earthquakes, 71 hybrid earthquakes and 77 rockfall signals. The hybrids were of very low amplitude and only triggered those stations nearest the volcano, they were scattered approximately evenly throughout the day with a maximum concentration of 6 an hour

The level of ash in the atmosphere in St Peter's and in St John's, as averaged over the last 24 hours, remained low.

The dome is still growing and the growth area may switch rapidly at any time. Although the main activity is currently in the south-west sector of the volcano, further pyroclastic flows are likely in any of the ghauts around the volcano.


Montserrat Volcano Observatory