Page:The origin of continents and oceans - Wegener, tr. Skerl - 1924.djvu/81

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GEOLOGICAL ARGUMENTS
57

explained in the present position of the blocks. Nevertheless, a complete comparison is not without interest. We find the fragments of an extensive basaltic sheet on the northern margins of Ireland and Scotland, in the Hebrides and Faroe Islands: it then changes via Iceland to the Greenland side, where in particular it forms the great peninsula bordering in the south on Scoresby Sound, and then continues farther along the coast up to latitude 75° N. Wide flows of basalt are also found on the coast of Western Greenland. At all these places coals containing land-plants occur in similar manner between two basaltic flows, whereby a former land connection has been concluded. The same result is yielded by the distribution of the terrestrial Devonian “Old Red” deposits in America from Newfoundland to New York, in England, Southern Norway and the Baltic provinces, and in Greenland and Spitsbergen. In their sum-total these discoveries give a picture of an area, united and continuous at the time of deposition, which to-day is broken up—according to former ideas, by the submergence of intermediate portions, but according to the displacement theory, by fissuring and drifting apart.

In this connection the similar occurrence of unfolded Carboniferous deposits on one side at 81° N. in north-eastern Greenland and on the opposite side in Spitsbergen is also worth mentioning.

The expected correspondence in structure also exists between Greenland and North America. According to the “Geological Map of North America” of the United States Geological Survey, numerous intrusive pre-Cambrian rocks occur in the gneiss-complex near Cape Farewell and north-west thereof. These are to be found again on the American side exactly at the corresponding places, namely, on the north side of the Straits of Belle Isle.