Greinar (Vísindafélag Íslendinga) - 01.01.1977, Blaðsíða 130

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extensive ice caps, there would not be a global cooling ((96),
(97)), which could explain the lack of indications of the Gond-
wana Ice Age in areas other than Gondwana. The mid-Pacific
polar region would not necessarily have expressed itself geo-
logically as a cold region.
Thus the arc-planes themselves would, in this theory, be
of Hercynian or possibly still earlier origin — if the pole posi-
tion was not much different, — while the Hercynian trends,
and possibly these planes, would influence Mesozoic and Alpine
trends.
The Pacific stress-pole given above, is 50° or 5500 km SE
from the magnetically found pole for the Carbo-Permian. It
would be interesting to see the result, if the paleomagnetic
material were sifted in accordance with the criteria given in
Chapter 4. As it happens, the unsifted paleomagnetic material
shows, in general, a movement of the Pacific North Pole to-
wards the present axis of rotation. This indicates that not all
the paleomagnetic material has been hopelessly falsified by
viscous movement of the vector of rock magnetization due to
strong crustal stresses under burial. But the claim is, never-
theless, valid that paleomagnetic material should be correct-
ed for effects of the stress and burial history of a rock in
question.
On the present theory, the submarine ridges now existing,
would mainly be an inherited structural feature from Her-
cynian time. Later stress fields, first in the Lower Tertiary
and finally much later, in the Pleistocene strong stress fields
revived the structural feature, and especially the rugged forms
should be taken to be of Pleistocene age. The revival of old
structure is not a new concept in geology.