Rit (Vísindafélag Íslendinga) - 01.06.1923, Blaðsíða 104

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b) Marine strata by Pverá (river) and in Örnólfsdalur,
(pp. 11-20).
Along the Þverá, raised terraces, formed by gravel, lami-
nated clay and sand, are very common. The clay terraces
mostly extend to 20 — 30 m. above sea-level and gravel
and sand terraces to 40 — 50 m. above sea-level. At the en-
trance to Örnólfsdalur there are ridges of sea worn gravel
that appear to have been formed by the action of the sea.
They reach to about 100 m. above sea-level. In the clay
terraces by the Þverá old shells are found in the follow-
ing five places, 10 — 25 m. above sea-level: Neðranes (or
Hamrendar) (the species enumerated on pp. 11 — 13); Hjarð-
arholtslandbrot (pp. 15 — 16); Kaðalstaðir (p. 16); Bugar (p.
17); and Steinar (pp. 17 — 18).
c) Marine formations along the river Hvitá, (pp. 20 — 24).
Marine terraces of laminated clay, gravel and sand are to
be found along the Hvítá as far as Hvítárdalur, 40 — 50 m.
above sea-level. At Deildartunga, on the south bank of the
river, the grave! plains or raised terraces, covered with sea-
worn gravel, reach to about 80 m. above sea-Ievel. The
author discovered some marine fossils in three places, 14 — 30
m. above sea-level, in terraces that extend up to 20 — 35 m.
above sea-level. (The species are enumerated on pp. 21—23).
d) Marine deposits by Reykjadaisá and Geirsá (rivers),
(pp. 24-26).
The sea must once have penetrated Reykholts valley,
very probably as far as the farm Giljar, where marine ter-
aces are common by the riverside, 30 — 50 m. above sea-
level. The author discovered the highest ancient tidemark
on the mountainside above the farm Stóri-Kroppur, where
marine terraces of stratified gravel are found 80 — 85 m.
above sea-level and above them a broad surf-formed ledge
in the solid rock (rock-terrace), about 115 m, above sea-level.