Jökull - 01.12.1978, Síða 25

Fig. 4. The relative distribution of stones
and boulders on the surface of Raudhóla-
sandur.
Mynd 4. Hlutfallsleg þekja hnullunga og .stór-
grýtis á Rauðhólasandi.
Miklafell an ice thickness of 300—400 m is
inferred. The question rises whether the
jökulhlaup at Raudhólasandur was caused by
the Miklafell eruption. Fig. 7 shows a topo-
graphic profile from Raudhólasandur to
Miklafell, and profiles of some Vatnajökull
outlets, supposed to be similar to the retreat-
ing Lateglacial ice in this area. About 20 km
Fig. 5. The proportion of basaltic and hya-
loclastite boulders on the surface of Raud-
hólasandur.
Mynd 5. Hlutfall basalt- og móbergsstórgrýtis á
yfirborði Rauðhólasands.
from the margin, the Vatnajökull outlets have
become 300—600 m thick. This may support
the hypothesis that the Raudhólasandur and
Miklafell were synchronous.
No direct continuation of marginal deposits
can be seen towards west or southwest from
Raudhólasandur. Glacial striae show that the
ice front was lying somewhere between
Raudhólar and Raudafell, and to the north of
Ásbjarnarhnjúkur (Fig. 1). Remnants of a
distinct end moraine were found to the west of
the river Vestari-Jökulsá. The material in the
ridges is rather fine grained till with almost no
boulders. There is no reason to doubt that
JÖKULL 28. ÁR 23