Montserrat Volcano Observatory

Daily Report
Report for the period 5 p.m. 5 November
to 5 p.m. 6 November 1998

There was elevated activity at the volcano during the last twenty four hours. During this period there were 28 rockfall signals, 18 volcano-tectonic events and 1 hybrid event.

There was a major collapse of the dome at 9.17 pm on Thursday evening. This eruption generated a large pyroclastic flow which reached the sea after descending the White River valley at Galways. This event produced a surge cloud which climbed over the northern slopes of Fergus Mountain in an almost similar fashion to the Boxing Day event but it did not cross over into St.Patricks.

The main pyroclastic flow arrived at the coast as two lobes, the larger portion exiting the valley mouth of the White River whilst a smaller over-spill lobe was deposited across the northern wall of the valley.

During this same eruption a small pyroclastic flow descended the ghaut at Gingoes and travelled a distance of approximately three kilometres to Brodericks.

The eruption produced a vertical ash column which rose to a height of 20000 feet and it drifted off to the north west. The prevailing wind conditions were such that there was no significant ash fall on Montserrat.

These pyroclastic flows were entirely associated with a major collapse of that fractured portion of the dome which abutted Chances Peak and to which reference was made in the reports of last week. There now exists, a deep chute between Chances Peak and the dome which most likely will facilitate further collapses of the dome into Galways or Gingoes. Geological sampling was done on the deposits which were produced on Thursday night as well as that which was produced at Tar River last Tuesday.

Residents of Montserrat are advised to keep listening to ZJB Radio Montserrat for information relating to any further developments in the state of the volcano.

Montserrat Volcano Observatory