Rit (Vísindafélag Íslendinga) - 01.06.1967, Side 33

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DISCUSSION
Thorleifur Einarsson: It has proved difficult to trace the
origin of Pleistocene sediments in Britain. Is it easier to trace
the origin of the much older sediments?
Trausti Einarsson: The main point is the recognition of a
southern sea bordering on a northern land; that tells the ori-
gin of the sediments.
Thorleifur Einarsson: The Beringland area has been con-
tinental since at least Mesozoic and was only submerged
some 3 million years ago. How does this fit with a west drift
of Greenland and N. America?
Trausti Einarsson: We must restrict our present discussion
to the Scandic area; the evidence found here should he judged
hy its own merits.
S. Thorarinsson: Drift is a fact hut we cannot discuss the
causes here. Would the second tectonic phase in Iceland not
have been contemporaneous with the uplift of Scandinavia
and other mountains around the Scandic?
Trausti Einarsson: Most likely. The geomorphologic history
of Norway seems quite similar to that of Iceland. In this case
the tectonic phase affected a much more extensive area than
the Ridge.
K. Saemundsson (written comment): Prof. T. Einarsson
claims that the geology of Iceland is best explained if we as-
sume four main phases: 1. The building up of the Tertiary
(and in part Quaternary) plateau; 2. Breaking up of the
plateau into several variously tilted hlocks; 3. Subsequent
peneplanation; 4. Second tectonic phase involving the forma-
tion of the present graben structures of Iceland.
I think this hypothesis is not tenable. The following objec-
tions could be raised.
1. The results obtained by Dr. Walker in eastern Iceland
are not in agreement with prof. T. Einarsson’s view. This is
most important because eastem Iceland is the only part of