Asker. Kvartærgeologisk kart 1814 I - M 1 : 50 000. Beskrivelse.

SKRIFTER
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90
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Forfattere
Nordahl-Olsen, Torkill
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Utgivelsesår
1989
Publikasjonstype
Utgivelsesår
1989
Summary
The superficial deposits within the area of map-sheet Asker, southeastern
Norway, are classified and described. The areas above the upper marine limit
(c. 220 m a.s.l) are dominated by exposed bedrock or a thin and discountinuous
cover of till. In the main valleys, below the upper marine limit, fine-grained
sediments dominate. These are commonly overlain by sandy and gravelly marine
shore deposits. Only small glaciofluvial deposits exist, mostly near the heads
of the main valleys. Weathering material overlies most of the Cambro-Silurian
bedrock along the inner part of Oslofjorden. Ice movements and the course of
the deglaciation have been reconstructed. The oldest ice movement was towards
south-east (with Oslofjorden as the confluence area). During the deglaciation
of the mapped area, there was only one main glacial event (the Aker Moraine
event) marking advance or half of the ice-front. The Aker Moraine is dated to
c. 9800 years B.P. Short accounts are given on shorelines, shorelevel displacem
nt and pollen analyses.
Kommune
OSLO
BÆRUM
ASKER
NESODDEN
Fylke
VIKEN
Tilgjengelig
NGU-biblioteket