Date:         Fri, 25 Nov 1994 20:29:03 MST
From: Boris Behncke 
Subject:      More on Merapi

According to press reports today (25 Nov 1994), the number of persons
killed in the 22 Nov Merapi eruption has now reached 37. This makes the
eruption MerapiŃs worst disaster since 40 years (64 deaths in 1954), and
the first to produce fatalities since 3 deaths in 1969. The press widely
reported 28 deaths in a November 1976 eruption; however, the few
reports on that event (e.g., Bulletin of Volcanic Eruptions 16) do not
mention fatalities.
Yesterday, German news papers carried a few spectacular (partly color)
shots of the pyroclastic flows descending the S flank of the cone. It is
noteworthy that on these photos there is absolutely no vertical eruption
column but large, dense plumes rising obliquely from succeeding pyro-
clastic flows. The repeated reporting of extensive burns on the victims
and of the incineration of vegetation and buildings suggests that the
event has been characterized mostly, if not exclusively, by the generation
of pyroclastic flows by the collapse of (part of the) large lava dome that
has been growing episodically on the summit since early 1992. Just one
month ago, Voight and others (GSA Abstracts and Programs Oct 1994)
warned that the dome had grown in a highly unstable position, not only
threatening the areas on the SW flank (that have been the major target of
pyroclastic flows since 1961), but also areas that have not experienced
such events since decades (such as the S flank now devastated). All in
all, the present disaster much resembles the June 1991 Unzen pyroclas-
tic flows that were caused by the collapse of a growing lava dome. The
reporting of "lava flows" as one of the destructive agents is certainly
incorrect.
Whether the fatalities are due to a lack of warning because the dome
collapse occurred quite instantaneously or to human ignorance in the
face of danger (some press reports indicate that some of those killed
had not respected "warnings" and remained in the high risk zone) is not
yet known. However, it is a sobering fact that so many were killed at
one of worldŃs most notorious volcanoes that had no less than 5 fatal
eruptions earlier in this century, including 1370 deaths in 1930.

Boris Behncke, Kiel
(bbehncke@geomar.de)