Montserrat Volcano Observatory

Morning Report
Report for the period 4 pm 13 September
to 7 am 14 September 1997

Activity has remained at an elevated level overnight, with rockfall and pyroclastic flow signals dominating the seismic records. A period of enhanced rockfall and pyroclastic flow activity occurred between 11 pm last night and 2 am this morning. Numerous large pyroclastic flow signals were recorded during this period. Activity has remained at a relatively high level following this period which occasional large pyroclastic flow signals. As reported yesterday, some of these events are preceded by long-period earthquakes. The northern flanks of the volcano are thought to be the most likely area where these flows were occurring. Other seismic signals have been at very low levels during the night.

The summit of the volcano is in cloud this morning. A helicopter flight is planned for later this morning to assess the extent of the pyroclastic flows which have occurred overnight.

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.

Rod Stewart left the island yesterday evening after a 3 week working holiday at MVO. Rod played a key part in Team Seismic during his visit.

Montserrat Volcano Observatory