Montserrat Volcano Observatory

Morning Report
Report for the period 4 pm 14 September
to 7 am 15 September 1997

Activity has continued to remain at an elevated level. Overnight there have been a number of VT earthquakes, a small hybrid swarm between 8:30 pm last night and 12:30 am this morning, several long-period earthquakes and a number of rockfall and pyroclastic flow signals.

The main period activity began at around 8:30 pm last night with the onset of the hybrid earthquake activity. Although the swarm comprised only about 20 events, some of the individual events were as large as any seen during the eruption so far. Following the end of this swarm rockfall and pyroclastic activity increased until about 2 am this morning. Following this period, activity has been relatively low although there have been some isolated rockfalls and pyroclastic flows.

The summit of the volcano is in cloud this morning.

The dome continues to grow faster than it sheds material. A large collapse could occur without warning and might lead to explosive activity. Pyroclastic flows from a large collapse can now get into the Belham Valley very easily and may reach the Belham Bridge or beyond. The Belham Valley might become filled with material very quickly, which could allow the flows to reach the Old Towne and Friths areas and the associated surges to get to Salem.

The southern part of Montserrat is extremely dangerous and all areas south of the Nantes River should be evacuated. Residents of Montserrat should remain vigilant and listen to Radio Montserrat for information. Ash masks should be worn at all times in ashy conditions.

Montserrat Volcano Observatory