Montserrat Volcano Observatory

Daily Report
Report for the period 6 pm 17 February
to 6 pm 18 February 1998

Volcanic activity has continued to follow the cyclic pattern of the past few weeks with elevated periods characterised by an increase in rockfall activity and continuous low amplitude volcanic tremor.

Peaks in activity occurred between 2am - 4am this morning and 12pm - 2pm this afternoon. During this second period there was a moderate sized pyroclastic flow down the Galways side of the volcano. A thick ash cloud from this event was observed over Plymouth.

Between 16:00 yesterday and 16:00 today there were 18 long period earthquakes, 7 volcano-tectonic earthquake and 65 distinct rockfall signals. The largest of the volcano-tectonic events was located approximately 4km below the top of the dome.

Work carried out today included setting up a GPS base station at Hermitage on the Eastern flanks of the volcano. This will provide continuous measurements of the ground deformation in this area.

Dust levels at all of the monitoring sites remained low today.

Montserrat Volcano Observatory