Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 11 May
to 16:00 12 May 1997
The current alert level is AMBER

Activity has continued at a low level during the past 24 hours, with a continuation of rockfall and small pyroclastic flows from the dome, and some long-period earthquakes.

The broadband seismic network recorded 100 rockfalls, which is a slight increase since yesterday. The number of long-period earthquakes was about the same, with 30 recorded. There were two small hybrid and no volcano-tectonic earthquakes. The number of long-period earthquakes in the last two weeks has been higher that at anytime in the last year. The long-period earthquakes are thought to be due to gas movement within the volcano, probably close to the surface.

The visibility has been very poor today, and only one brief glimpse of the dome was possible.

Visits were made today to the crater rim at Farrell's and Chances Peak, to plan the installation of new equipment. A tiltmeter and a seismometer will be installed in a hut on Chances Peak in the next few days, and new EDM reflectors and a tiltmeter are planned at Farell's.

EDM measurements were made at Amersham and Chances Steps, and these showed no significant changes since the last measurements.

The volcano remains dangerous, and only essential visits should be made to the evacuated zone. People should wear masks when in the ashy areas. The Tar River and White River valleys are extremely dangerous, and should not be entered under any circumstances.

Montserrat Volcano Observatory