Rit (Vísindafélag Íslendinga) - 01.07.1962, Qupperneq 84

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tionship between dipping breccia layers and covering lavas
is found in many cases. A likely explanation seems to be the
change from subaquatic to subaerial conditions (cf. for in-
stance Bláfell p. 92).
At the south end of the wall further important details can
be studied, Fig. 41. The lower main mass is an unstratified
breccia, closely similar to that of the north corner. Here we
find whole bombs, crumbled but not disintegrated bombs,
crumbled bombs drawn out and distorted, and bomb “ghosts”,
Fig. 41. Hrafnabjörg, southern wall.
X = place where disintegration of bombs was studied; Y = yellow
tuff layer that can be traced vertically down along the dislocation
breccia at Ieft.
and finally bomb fragments where no trace of the original
bombs are left. It is clear that here we have a mass formed
by the crumbling of bombs through the movement of the
mass as a whole. Predominant are the basalt fragments (with
sparse small phenocrysts), 5—10 cm in diameter, mostly
with glass coating left on one side, although sometimes the
glass crust is worn off; further there are glass fragments and
the glass flour formed in the crumbling process. And in addi-
tion there are bombs in the various stages of crumbling and
disintegration.
At the north end of Hrafnabjörg we have, as stated, an ori-
ginal stratified tuff-breccia which merges into an unstrati-