Rit (Vísindafélag Íslendinga) - 01.06.1923, Page 109

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first had receded considerably below this line and after-
wards rose again up to 40 — 50 m., in which case this
boundary must indicate the upper limit of a separate sub-
sidence of the land or a rise of the sea.
Some observations are also mentioned which seem to
indicate that there have been two distinct risings of the
sea level. For example, the clay strata in some marine
terraces below the 40 — 50 m. line are divided in two, being
separated by fairly thick strata of gravel and sand (Figs. 1
& 7). But at present there is not enough material in hand
to decide this with certainty.
5. Beach-peat and indications of a rise in the sea-
level in recent times, (pp. 65—68).
ln this chapter is discussed the beach-peat found between
high- and low-water marks in the beach of Faxaflói (Akranes,
Borgarnes, Seltjarnarnes, Álftanes and Garðskagi). This peat is
covered by beach, marine gravel and sand, and underneath
it are also old marine strata. It contains twigs and roots of
birch and willow and distinct remains of other land plants.
When this peat was formed the sea-level must have been
at least 4 —5 m. lower than at present, (equal to the differ-
ence between high and low water). Since then the sea-
level has been raised and reached its present height, and
the sea has covered the submerged peat with gravel and sand.
6. Changes in the sea-level in present times, i.e.
since Iceland was inhabited, (pp. 68—77).
According to the information collected by the author, it
is the common opinion that the sea-level is getting lower,
or the land is rising, on the north coast of Iceland (in
Húnaflói) and at the west coast (in Vestfirðir) and the
northern and inner part of Breiðifjörður. On the other hand
it is said that on the south coast of Breiðifjörður (Snæfells-