Montserrat Volcano Observatory

Daily Report
Report for the period 16:00 14 November
to 16:00 15 November 1996
The current alert level is ORANGE.

Activity at the volcano has been low during the past 24 hours, with the latest volcano-tectonic earthquake swarm ending yesterday evening. Despite the low level of activity, the scientists remain highly concerned about the possibility of dome explosions.

The volcano-tectonic earthquake swarm ended at 21:51 yesterday, having lasted for 20 hours. The swarm comprised 41 earthquakes, located at shallow depths beneath the crater. This swarm was the smallest recorded since the level of activity increased on 01 November. However, the largest VT, recorded at 21:32 last night, was larger than any recent earthquake, and had a magnitude of about 2.5 on the Richter scale. Other seismic activity has been scarce today, with only a few small rockfalls and two small long-period earthquakes.

The viewing conditions at the volcano were variable today, and allowed good views of the October 1 dome from the helicopter. There has been a noticeable increase in the size of the dome since yesterday. New, light-coloured, blocky material has appeared on the northern side, along with some material on the south side of the new dome. The top of the dome is blocky with several small, stubby spines. Vigourous steaming was observed from the southern part of the scar and near Castle Peak.

EDM measurements were carried out today on the eastern triangle between Long Ground, Whites and Castle Peak. No changes in line length were detected since the triangle was last measured yesterday.

A GPS survey was completed on the western side of the volcano. As usual, the results will take some time to process.

Scientists at MVO remind everyone that the volcano is still in a very dangerous state and all residents should follow the recommendations laid out in the alert procedures and listen to Radio Montserrat. The recent earthquake swarms, combined with slow dome growth, represent a new type of activity at the volcano, and thus we cannot be sure what will happen during the next few days and weeks. A rapid escalation to explosive activity is possible at any time. The Tar River and Long Ground areas remain especially dangerous and anyone entering these areas is putting themselves at risk of death.

Montserrat Volcano Observatory