Montserrat Volcano Observatory

Morning Report
Report for the period 4 pm 19 August
to 7 am 21 August 1997

Activity at the volcano remains at a high level. After a period characterised by rockfalls and small pyroclastic flows throughout yesterday afternoon and evening, hybrid earthquakes began at around 10 pm. This resulted in a swarm of events which lasted until around 2 am. Activity then peaked in a series of rockfalls and pyroclastic flows. The largest pyroclastic signal was recorded at around 2:30 am this morning.

There have also been signals recorded by the seismic network which are due to regional earthquakes. MVO are awaiting confirmation of location of these events from the Seismic Research Unit in Trinidad.

Further explosions may take place with little or no warning. These may be more intense and longer lasting than those already experienced. If explosions do occur, people should seek shelter under as strong a roof as possible and have a helmet or head protection available. After an explosion small rocks and ash can be expected to fall everywhere on the island. Ash and falling rocks make driving hazardous. Ash is present in the atmosphere and masks should be worn outdoors.

Pyroclastic flows are expected on all flanks of the volcano, and so at no time is it safe to enter the exclusion zone, including the Belham river valley. Access to the exclusion zone is completely restricted. The areas south of the Nantes River have been evacuated over night. Everyone should remain vigilant and continue to listen to Radio Montserrat for any announcements.

Montserrat Volcano Observatory