Rit (Vísindafélag Íslendinga) - 01.07.1962, Qupperneq 37

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changed its course, which has saved them from Pleistocene
erosion.
At the southern end of Bakkabrúnir the Young sediments
and the covering lavas extend across the river (Víðidalsá)
and are seen in the eastern wall of its gully where the river
Bergsá joins in a large waterfall from the east. Following
the Bergsá above the waterfall, Fig. 19, we first trace the nor-
mal Young basalts for a while (a). Then the rock is hidden
on a 50 m stretch, whereupon we meet (on the north side of
the river) the uplifted Young sediments (b), and then at
a clear fault (f3) at which a small waterfall occurs come
i
Fig. 19. Section along Bergsá.
Explanation in the text.
basalts of reverse magnetization (c). These are, in my opi-
nion, the basement of the Young roc.ks. These basalts are
seen to be covered by a thick coarse conglomerate which in
tum is covered by a columnar lava of reverse magnetization.
This displacement at f3 is younger than the Young rocks and
it is suggested that the relative sinking of the left side has
saved the Young rocks from disappearance, while on the
higher right side they are completely lost, if the thick conglo-
merate and its basalt cap do not in reality helong to the
Young rocks.
The observations here related suggest that the Young rocks
at Bakkabrúnir may belong to the lower part of the Young
volcanism, possibly corresponding to the section at Bríkar-
kvísl, and that their present level has been much influenced
by later tectonic movement. It is at any rate questionable
that the young lavas here flowed from the Heaths into the