Montserrat Volcano Observatory

Morning Update
Report for the period 16:00 06 September
to 07:00 07 September 1996

Activity at the Soufriere Hills volcano during the night continued at about the same relatively low level as observed during the previous reporting period. A swarm of volcano-tectonic and hybrid earthquakes was recorded yesterday 06 September from 17:06 to 21:23. Preliminary calculation of the locations of some of these events places them at shallow depths beneath English's Crater. The number of rockfalls, which were mainly small- to moderate-sized, remained relatively low, with the largest being recorded at 22:22 on 06 September. This was probably associated with a small pyroclastic flow and ash cloud. Intermittent low-amplitude broadband tremor was recorded at the stations closest to the Crater. A moderate-amplitude broadband signal which was recorded at the Gages seismic station for more than 40 minutes from 03:51 this morning was due to flash flooding in Fort Ghaut.

Visibility was very poor during the early morning period because of low cloud cover on the volcano.

Further rockfalls and pyroclastic flows will occur but all indications at the moment are that the pyroclastic flows will be confined to the Tar River Valley area. However, areas affected by associated ashfalls will obviously depend on the direction and strength of the wind at the time. Extreme care should still be taken when driving in ash affected areas. Dust masks should be worn at all times in ashy environments.

The Tar River Valley and surrounding areas are extremely hazardous and should not be entered under any circumstances.

Montserrat Volcano Observatory