Rit (Vísindafélag Íslendinga) - 01.07.1962, Qupperneq 164

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have developed on Langahlíð in the uplifted position. These
valleys mtist, I think, be considered as older than the uplift.
We then have to add the erosion period to the post-tectonic
time and it seems very difficult to avoid the conclusion that
the dolerite goes hack to the Gúnz-Mindel interglacial at
least. But as long as precise knowledge of the time of the
magnetic transition from reverse to normal is lacking the date
of the dolerite remains uncertain. Ahsolute dating of the dole-
rite and the transition in Skagi would be of fundamental
geomagnetic importance.
Clear traces of the strandplane stage are not seen on the
Reykjanes peninsula; the strandplane underlies the dolerites
and is here below sea-level.
In the Southern Lowlands the situation is complicated and
a discussion will be postponed for a while.
Going farther east we have an unbroken low plain in front
of high scarps all the way from Landeyjar to Homafjörður.
Considerable parts of this are probably due to relatively late
marine erosion and should be comparable with the strand-
plane on the south side of Snæfellsnes which we have dis-
cussed earlier. But with Homafjörður we reach again dipp-
ing older basalts and here the wide plane is most naturally
referred to the strandplane stage; the height is here generally
below 20 m, only individual remnants reach about 40 m. The
strandplane is further quite clear in the areas Lón, Álfta-
fjörður, the mouth of Berufjörður but farther north it is not
conspicuous.
In the area of Younger rocks from Thistilfjörður to Tjör-
nes tracing is difficult because of coverage with very young
lavas and because of movement.
2. Signs of higher base levels.
In the tuff-breccia mountains to the east of the Southern
Lowlands we find clear signs of higher base levels and we
shall first consider these although in most other respects we
are leaving this area outside our present study.
Skaftártunga, Sí'Öa, Fljótshverfi. Above the Síða district