Sample Reports on Volcanic Activity

Following are some sample reports on volcanic activity on Montserrat
as circulated by Midge Kocen and/or Tony Glaser to the MNI-INFO Members:

. . . The Electronic Evergreen, courtesy of GEM Radio Network
From Mon Feb 24 13:18:02 1997
Date: Sat, 22 Feb 1997 12:50:22 -0400
From: Midge Kocen 

Via MNI-INFO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Over the last week the activity at Soufriere Hills Volcano in Montserrat
has been at a low level. This has led to a reduction of the alert level
from ORANGE to AMBER and the publication of a new risk map.

Residents are now allowed daytime access to all areas except Zone A which
is the closest zone to the volcano and the most dangerous. However
residents are urged to have a rapid means of exit from unsafe zones, a
transistor radio so that they can keep tuned to Radio Montserrat for
updates and a dust mask for times of ashing and for when cleaning up.

In the evening there is no access to Zones A, B, and C as these are under
curfew from dusk to dawn. Scientists are informing residents that the
activity has reached a plateau at the volcano and that everyone who needs
access into the unsafe zone should take the opportunity now whilst the
activity is quiet.

However scientists also warn that there will be increased activity soon as
the dome is very steep and unstable. A survey of the dome completed mid
week shows that it is now the largest it has ever been, in the region of 40
million cubic metres and growing at the rate of 3 cubic metres per second.

There have been swarms of volcano-tectonic and hybrid earthquakes during
the week and these have led to rockfalls and small pyroclastic flows. There
have been some small ashclouds blown westward by the prevailing winds
leading to minor ash falls.

The Galway's Wall also shows evidence of further deterioration and small
pyroclastic flows have reached the Upper Galways area traveling a distance
of about 1 kilometre.

Most of the activity is on the south eastern face of the dome and on clear
nights glowing magma can be clearly seen. Major pyroclastic flows are
expected to travel down the Tar River Valley from this south eastern face.

The estimated shelter population is now 800 and so far Government has
constructed over 60 family unit homes to take people from shelters. More
are to be started shortly.

Public Works continue to clear Fort Ghaut in Plymouth of Volcanic debris
which has been deposited there by recent heavy rains causing flooding.

The first phase of the Emergency Jetty at Little By in the North of the
Island was finished this week. It is being constructed by British Funds and
is designed as a re-supply jetty and evacuation facility in case of closure
to Port Plymouth.

(GIS Montserrat 21 February 1997)

Midge Kocen                        ()
Midget Services 	            ()
Plymouth, Montserrat 		      ()
West Indies	                        ()_
                             /\   __   / \ Soufriere Hills Volcano
                            /  \ /  \ /   \
                           /    \    /     \

. . . The Electronic Evergreen, courtesy of GEM Radio Network
From Mon Feb 24 13:19:04 1997
Date: Sat, 22 Feb 1997 13:04:38 -0500 (EST)
From: Tony Glaser 
To: Montserrat E-mail group 
Subject: mvo evening report (fwd)

Via MNI-INFO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sorry this is late, my local service provider was off-line for about 18
hours for scheduled maintenance.

Tony Glaser

---------- Forwarded message ----------
Date: Fri, 21 Feb 1997 17:45:51 -0800

Montserrat Volcano Observatory

Montserrat, W.I.

Report for the period 16:00 20 February to 16:00 21 February 1997

The alert level is Amber.

The level of activity at the volcano has remained the same, with a
continuation of earthquake swarms.  There were few visible changes to the

Seismic activity has been dominated by two swarms of earthquakes, with a
total of 261 hybrid and 100 volcano-tectonic earthquakes recorded.  The
first swarm was from 3:44 pm to 11:43 pm yesterday, and the second from
8:45 pm to 2:31 pm today.  Both swarms were similar to the swarm earlier
yesterday, with volcano-tectonic earthquakes followed by repetitive hybrid
earthquakes. The established pattern continues, with about 14 hours
between the swarms.  The first swarm was slightly less intense than the
second, with 121 hybrids and 137 hybrids, respectively.  At it's maximum,
the second swarm had hybrid earthquakes at a rate of one per minute, and
afterwards developed into a short period of low-amplitude, continuous
tremor.  Otherwise, the level of seismic activity was low, with only 18
rockfalls recorded.  As usual, the earthquakes were too small to be felt. 

Visibility was mixed during the day.  There were a few small pyroclastic
flows around midday, coinciding with the hybrid earthquakes.  A helicopter
inspection of the dome revealed few changes in the last two days.  Some
deep gullies have developed at the top of the eastern face, and a small
fan of fresh debris has developed on the north-east side of the dome. 
There continue to be gradual changes to the top of Galway's Wall, with
fresh rockfall deposits almost reaching to the road at Galway's Soufriere. 

The extensometer across the crack near the Galway's Wall, to the east of
Chances Peak, has shown some changes in the last few days, coincident with
swarms of volcano-tectonic earthquakes.  The crack which is monitored
continuously, has widened by between 3 and 10 mm at the same time as the
last three earthquake swarms.  This indicates that slow deformation of the
wall continues, and is related to the earthquake swarms. 

No EDM or GPS measurements were made today.

The dome is currently larger than ever before, and further dome collapses
and pyroclastic flows are expected.  These will probably follow the recent
pattern, but a change in the activity could occur at any time.  Visitors
to zone C are reminded to remain alert at all times, and spend the minimum
possible time in the evacuated zone.  Ash levels in Plymouth are
hazardous, especially during dry, windy weather, and so it is essential to
wear masks in areas affected by ash.  Flash floods could cut off access to
areas south of Fort Ghaut; visitors should leave that area when it rains. 
The Tar River Valley and the upper Galway's area are very dangerous and
should not be entered at any time. 

16:00, 21 February 1997 ?? 

first version: March 2, 1997; file:/~ehem/car/islands/mts_sample_repts.html;

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