Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 23 January
to 16:00 24 January 1997
The current alert level is ORANGE

As during the previous 24 hour period, the volcano has remained in a quiet state, with the seismic activity dominated by two volcano-tectonic earthquake swarms. There has been poor visibility all day, and no views of the crater area have been possible.

A total of 54 volcano-tectonic earthquakes were recorded, in two swarms between 4:54 pm and 7:08 pm last night and 3:06 am and 05:25 am this morning. The second swarm was more severe than the first. Most of these earthquakes were small, occurring at depth shallower than 2 kilometres beneath the crater. Nine hybrid and five long-period earthquakes were also recorded.

The Gages seismic station recorded two flash floods that came down Fort Ghaut this morning at 3:17 am and about 2:00 this afternoon. The floods caused more material to be deposited in the lower reaches of the Ghaut in Plymouth. Ash laden floods were also reported in White's Ghaut and other ghauts south of Fort Ghaut.

MVO fieldwork today has been hampered again by low cloud and rain. Observers at Whites this morning were not able to see the top of the dome, and thus it is not possible to confirm if the rapid dome growth has continued since most of the dome was last seen. Rock samples were taken from the delta. COSPEC measurements and a Gravity survey were taken but the results are not ready for publication.

All the signs are that the current phase of activity has continued, with dome growth in the south-eastern sector of the dome. Further pyroclastic flows are likely in the next few days. Although the dome is likely to collapse in small chunks, producing small to large pyroclastic flows, a major collapse can not be ruled out. Should this occur, another explosion similar to that of September 1996 could result. It is however expected that there would be several hours of high level pyroclastic flow activity before any explosion. Zone E, which includes Cork Hill and the airport, remains safe.

Montserrat Volcano Observatory