Náttúrufræðingurinn - 1984, Side 74

SUMMARY
Sealevel changes in central
south Iceland
by
Einar H. Einarsson,
Skammadalshóli, Mýrdal,
V-Skaftafellssýslu
In central south Iceland, i. e. along the
coastline from Holtsós at Mýrdalssandur,
no traces of raised beaches are observed.
In front of the numerous gullies in this
area, which are eroded into the hyalo-
clastite bedrock, no gravel deltas are found.
This is thought to be so, because the sedi-
ments, which the rivers carried with them,
were deposited in the sea, which thus must
have been at lower level than the mouths
of the gullies when pleistocene ice-sheet
was melting. In several places along the
coast, e. g. at Stóra-Borg, and Dyrhólaey
the land has been subsiding, at least since
time of settlement, i. e. from the 9th cent-
ury A.D.
In the area under discussion, the eastern
volcanic zone in Iceland reaches the sea. It
is proposed here that the volcanism has
been intense enough to compensate for the
reduced weight on the land when the
pleistocene ice-sheet disappeared, so no
isostatic uplift occurred as did elsewhere in
Iceland.
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