Greinar (Vísindafélag Íslendinga) - 01.01.1977, Blaðsíða 119

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Hercynian and Mesozoic orogeny along western Norway would
have been greater.
The sediments along Norway joined the fate of the east
coastal American ones of a similar age: they subsided in steep
steps down to the floor of a deep sea, the Norwegian ones down
to a 4 km deep one, most likely in the general sea-floor sub-
sidence at the end of the Oligocene, whereas Norway had been
uplifted and tilted eastward earlier in the Oligocene, as in-
ferred in Chapter 2, on the basis of the morphologic com-
parison with Iceland. The tilt of Norway deprived the coast
of sediments in the Oligocene (cf. Chapter 2), and on through
the Upper Tertiary. The material that now goes to the west,
remains at the ends of long and deep f jords, and a northward
current must cause longshore drifting of the finer material
towards the Barent Sea, but we lack here a peninsula to match
Florida, probably the transport of coarse material is too small
to form here such a peninsula.
We now turn our attention to southern Europe and Asia.
These continents furnished huge amounts of material to a
southern border-area. This material is now found in the
Alpine-Himalayan range.
But in Burma, there is a very significant turn of the oro-
genic belt to the south, continuing along Sumatra, Java, New
Guinea and farther. The greatest significance of this is the
fact, that in this trend the Alpine orogeny closely follows
Hercynian and Mesozoic orogenic belts, which go on to eastern
Australia and New Zealand.
In this connection, we also remark that the Alpine sharp
bend in southern Alaska follows closely a Mesozoic and Her-
cynian trend, all tracable for some distance out into the
Aleuten arc. This island arc thus begins as an orogenic arc
of several geological epochs, but is now mainly visible as a
young volcanic island arc. This arc as a whole is then hardly
independent of old structure. Rather, it must be determined
by an old stable shore line.
The mentioned repetition of orogeny is most easily under-
stood, as in the above discussed case of the east coast of