Page:The origin of continents and oceans - Wegener, tr. Skerl - 1924.djvu/130

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104
THE ORIGIN OF CONTINENTS AND OCEANS

equator of the early Tertiaries, the Carboniferous equator consists of a girdle of mountain folding (“Karbon-ring” of Kreichgauer), which certainly points to especially favourable conditions for the formation of bogs, since it contains the great coalfields referred to. It will be noticed, however, that the belt of folding of Kreichgauer deviates enormously in North America, and also in Australia, from the “Karbon-äquator,” and that in South America, which is cut through by the latter, such a mountain region is quite absent. Also the position of the equator does not fit in with the climatic evidences. By the comparison of this map with that drawn from the standpoint of the displacement theory (Fig. 17), it is clear that the zone of equatorial rains can only be truly represented in the latter.

The chronological sequence of the great occurrences of coal harmonizes with the position of the South Pole derived from the glacial deposits. Tropical coal occurs in the Carboniferous, also in Spitsbergen, and according to Andersson, amounts to more than two-thirds of its total coal resources. But this coal is Lower Carboniferous (Culm). It lies about 90° from the traces of ice-action in Togoland, the Congo and Brazil, the formation of which we also placed in the Lower Carboniferous. The plant remains, here also, are tropical, just as the corresponding ones in North-east Greenland at 81° latitude and on Melville Island. We are manifestly still dealing with the zone of equatorial rains of the Lower Carboniferous. On the other hand, the coals of the chief girdle of coal measures are in the main later; the Chinese coals are partly placed in the Lower Carboniferous (Shantung and Southern Szechwan), partly in the Upper Carboniferous (northern slopes of the River Nanshan), partly in the Permian (Shansi, Chihli, Manchuria), or even in the Trias (Hunan).[1] In Europe

  1. F. Frech, “Die Kohlenvorräte der Welt,” Finanz- und Volkswirtschalftl. Zeitfragen, Heft 43. Stuttgart, 1917.