Montserrat Volcano Observatory

Daily Report
Report for the period 6 pm 6 January
to 6 pm 7 January 1998

Activity at the volcano today was very similar to that of yesterday. Between 16:00 yesterday and 16:00 today there were 35 hybrid earthquakes, 55 rockfall signals, 9 long-period earthquakes and a small volcano-tectonic earthquake. The poorly developed cyclicity of recent days appears to have continued today, although its style has changed so that the 6 to 8 hour peaks are less sharp.

Cloud continues to mask the upper parts of the dome. However, rockfall activity on the southwestern flank of the volcano suggests continued rapid dome growth in the Galway's sector. Visual observations of the area where the Galway's Soufriere used to be show that new rock fall material is already filling up the depression left after the Boxing Day dome collapse and landslide. Activity on other sectors of the dome seems to be at a low level.

A single line GPS survey was undertaken today between Harris Lookout and Hermitage. The results show a shortening on this line of 1.1 cm (half an inch) since mid-December. This rate is high relative to what it was for most of last year, and further surveys will be undertaken to ensure close monitoring of this deformation.

Various field activities have been undertaken by MVO over the past couple of days. These have included maintenance of seismic stations, the start of installation of the remote camera and weather station on the Centre Hills and installation of blast meters to measure the force of pyroclastic flows. These activities will continue over the coming days and weeks to ensure that the monitoring capability is kept at an optimum level. Residents of Montserrat should thus not be unduly concerned at the higher than normal helicopter usage.

Professor Barry Voight arrived on Montserrat this morning for a visit to help assess the Boxing Day collapse and install new monitoring equipment.

Air quality at all monitoring stations across the island is good today.

People should remain alert and listen to Radio Montserrat for further information.

Montserrat Volcano Observatory