Montserrat Volcano Observatory

Morning Report
Report for the period 4 pm 11 October
to 7 am 12 October 1997

There was an explosion at 5:57 pm yesterday evening (October 11). This was associated with pyroclastic flows down Gages Valley, Tyer's Ghaut, Tuitt's Ghaut and the Tar River Valley. This event produced a wide column which was blown toward the north and north east. Fallout from the co-ignimbrite ash cloud generated by the pyroclastic flows and the main plume occurred over much of Montserrat. Low amplitude tremor continued for approximately 90 minutes after the explosion.

The volcano has been relatively quiet for the remainder of the reporting period. Overnight there have been a small number of hybrid earthquakes and some rockfall signals recorded by the seismic network.

Further explosions are expected and, although these will probably be similar in size to those experienced already, longer explosions fuelling more vigorous pyroclastic flows are a distinct possibility. There has been little seismic activity before the last few explosions and no warning is expected before further events. All residents remaining in Frith, Old Towne and Salem are thus urged to move out as soon as possible.

After an explosion, fallout can occur anywhere on the island. People should shelter in a strong building and wait for the fallout to end. If this is not possible then hard hats or other suitable protection should be worn. Avoid driving during or immediately after ashfall if at all possible. The roads are very ashy this morning and drivers should be very careful. The wearing of ash masks is recommended at all times. Everyone is advised to keep listening to Radio Montserrat for information on the activity.

Montserrat Volcano Observatory