Náttúrufræðingurinn - 1990, Page 58

6. mynd. Berghlaup sem féll haustið 1972 í Jökulsárgili vestan við Sólheimajökul. Hlau-
purðin er afmörkuð á myndinni. Mynd tekin 10. nóvember 1976. A rock slide that fell in
Jökulsárgil at Mýrdalsjökull, South Iceland in 1972. The picture is taken in November
1976 and shows the scar in the mountain slope and the rock slide across the glacier.
Ljósm. photo Oddur Sigurðsson.
Ólafur Jónsson 1976. Berghlaup. Rœktun-
arfélag Norðurlands. Akureyri. 623 bls.
SUMMARY
Möðrufellshraun, a rock slide or a
moraine
by
Oddur Sigurðsson
Orkustofnun
Grensásvegi 9
IS-108 REYKJAVÍK
Iceland
In a newly published popular handbook
on the nature and history of Iceland (ís-
landshandbókin 1989) a certain geomorph-
ological phenomenon - here exemplified
by Möðrudalshraun - is explained as be-
ing cirque-glacier moraines. In an older
and thorough study by Ólafur Jónsson
(1976) Möðrufellshraun is explained as be-
ing a rock slide.
The present author analyzes the glaci-
ological conditions needed to account for
the existence of the cirque-glaciers and
finds that these have not been present in
the region during Post-glacial time, which
is the age of the discussed phenomenon.
The new explanation is thus found to be in
error.
No arguments have been put forward to
justify the need for a new explanation and
the old one, a rock slide, is still considered
to remain valid.
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