Date:         Thu, 8 Dec 1994 09:07:28 MST
From: Boris Behncke 
Subject:      Merapi still active

The recent discussion on this net about the Merapi eruption gives
evidence that there might well be of you out there interested in the
following about more recent Merapi activity:

The eruption of Merapi is continuing. German newspapers (e.g.,
Frankfurter Allgemeine) today (6 Dec) report that on Sunday (4 Dec),
there were 18 eruptions of "lava"; however, none of the flows reached
inhabited areas. This almost certainly means that there were new pyro-
clastic (not lava) flows derived from a lava flow that is being extruded
on the S flank of the volcano (as reported recently by the DHA,
Geneva). The lava flow itself should be expected to be highly viscous
and therefore must be restricted to the very summit area, or to a breach
on the upper S flank that may have formed during the intense activity
of 22 Nov.
If so, Merapi would just be repeating a pattern seen several times
before during this century, like, for example, in 1930. The current
eruption has so far been quite typical, with the exception of the
change of direction (the last eruption to affect a sector other than
the W to SW sector occurred in 1954, towards the N and NW
The emplacement of a lava flow on the oversteepened upper flank
poses the high risk of more, and larger, pyroclastic flows towards the
newly-stricken direction. It has repeatedly been the case (e.g., in 1961)
that after the opening of a new summit breach, a large lava dome has
grown to fill that depression, and then, after several months of vig-
orous growth, it collapsed.

Boris Behncke