Montserrat Update 001
Date: Wed, 19 Jul 1995 10:51:23 MST
From: Global Volcanism Network
Subject: Soufriere Hills, Montserrat
The following report from the Smithsonian Institution's Global
Volcanism Network on 19 July 1995 is preliminary and subject to
change as additional information is received.
Montserrat, West Indies
16.72 N, 62.18 W; summit elev. 915 m
The Associated Press reported a "full alert" on the island of
Montserrat Tuesday (18 July) after a light ashfall. The director
of an emergency operations center told AP that no mass evacuation
was planned, but two schools had been set aside as refugee
centers for those living near the volcano who wanted to evacuate.
The Synoptic Analysis Branch of NOAA saw no evidence of a plume
on satellite imagery.
The following information is from a telephone report to GVN on
the morning of 19 July from Richard Robertson at the Seismic
Research Unit, University of the West Indies, Trinidad. Based on
his conversations with Montserrat residents, this eruption
appears to have been a small phreatic event with minor ashfall
being spread around the island by local winds. The UWI maintains
two seismic stations on Montserrat. Seismicity has been elevated
for the past three years, and an earthquake swarm was recently
recorded. William Ambeh and Lloyd Lynch have been dispatched
from UWI to confirm the activity. They will prepare a report for
the GVN Bulletin upon completion of their investigation.
Soufriere Hills volcano has grown on the N flank of the older
South Soufriere Hills volcano at the S end of Montserrat Island.
The summit area consists primarily of a series of lava domes
emplaced along a ESE-trending zone. The youngest dome, Castle
Peak, is located in English's Crater, which is breached to the E.
Block-and-ash flow and surge units associated with dome growth
predominate in flank deposits. The capitol city of Plymouth lies
on the coast, ~4 km W of the summit.
An active fumarolic area, named Galways Soufriere, is located on
the S flank of Soufriere Hills. There have been no reported
historical eruptions, but some undated deposits and the cone have
a young appearance. A radiocarbon date of ~320 BP from a
pyroclastic-flow deposit is significantly younger than other
radiocarbon dates from the volcano, but could result from the
latest activity of Castle Peak.
Global Volcanism Network | Phone: 202-357-1511
Museum of Natural History, MRC 129 | Fax: 202-357-2476
Smithsonian Institution |
Washington, DC 20560 USA | Internet: mnhms017@SIVM.SI.EDU