Montserrat Volcano Observatory

Morning Update
Report for the period 16:00 10 September
to 07:00 11 September 1996

Activity at the Soufriere Hills volcano during the night continued at about the same level as that observed during the previous reporting period. Seismicity was dominated by volcano-tectonic earthquakes which occurred in two swarms from 17:25 to 20:00 yesterday 10 September and from 04:30 to the end of this update period. Preliminary estimates suggest that these events are located below the Crater at shallow depths, similar to other recent VTs. Several small- to moderate-sized rockfalls were also recorded. Intermittent broadband tremor occurred throughout the update period.

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