Jökull - 01.12.1956, Blaðsíða 16

Fig. 13. The moraine
hillocks Kvíárhólar.
To their left the slope
of Kviármýrarkambur.
Photo S. Thorarinsson
16 Sept. 1955.
(Ives ancl King 1955, p. 478). My impression
from a short visit in 1945 was that these
“moraines” might be early postglacial dead ice
moraines. There is no doubt that they are
prehistoric, but nothing more can as yet be
said with certainty about their age. Also here
a tephrochronological study woulcl probably
prove useful for dating the moraines.
Finally it should be mentioned tliat shortly
W of the road between Svínafell ancl Sandfell,
ab. 2 km in front of the present snout of Fall-
jökull, there are prehistoric terminal moraines
called Rasshólar. They could be of the same
age as the moraines in Morsárdalur and Staclar-
dalur.
The conclusions cjuoted at the beginning of
this paper, viz. that the moraines which were
formed during the advance of the glaciers
around the northernmost Atlantic in the 18th
and 19th centuries mark their maximum extent
in historical and probably even in postglacial
time, are in my opinion still valid for the bia;
outlets of Vatnajökull, but the tephrochrono-
logical studies in Oræfi related in this paper
support the view that some of the outlets of
Oræfajökull advanced in early Subatlantic.
Time as far ancl even a little further than
in the 18th and 19th centuries. The reason
why the outlets of Vatnajökull proper did not
in early Subatlantic Time advance as far as the
outlets of Öræfajökull, compared with their re-
cent advances, might then simply be that at
the end of the Postglacial Warm Period Vatna-
jökull proper was proportionally more reduced
in area than the higher and more alpine Öræfa-
jökull (cf. Eythórsson 1951 a). The rising of the
firn line during the Warm Period liad a greater
reducing effect on the big Vatnajökull outlets
with their relatively flat spoonshaped intake
areas than it hacl on the steep alpine Öræfa-
jökull outlets. But we must also take into con-
sideration that Öræfajökull is an active volcano,
as that may have affected its outlet glaciers.
REFERENCES:
Ahlmann, H. W:son: 1933. Scientific Results of
the Swedish-Norwegian Arctic Expedition.
Part VIII. Glaciology. Geogr. Ann. Stockh.,
15: 161-216, 312-348. Stockholm.
— Glaciological Research on the North At-
lantic Coasts. R. G. S. Research Series No 1.
London.
Bárdarson, G. G.: Islands Gletscher, Vísindafál.
Isl. 1. Reykjavík.
Eythórsson, }.: 1935. On the Variations of
Glaciers in Iceland. I. Drangajökull. Geogr.
Ann. Stockh.
— 1949. Variations of Glaciers in Iceland 1930
-1947. Journ. Glaciol., 1: 250-252. Cambr.
— 1951 a. Þykkt Vatnjökuls. Jökull, 1: 1—6.
Reykjavík.
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