Page:The origin of continents and oceans - Wegener, tr. Skerl - 1924.djvu/78

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THE ORIGIN OF CONTINENTS AND OCEANS

up to the present there had to be assumed a submerged central portion that would be longer than the visible ends known to us, a fact which Penck felt a considerable time ago to be a difficulty. Several isolated elevations of the sea floor lie along the line of junction of the points of fracture which have been considered up to the present to be the tops of the submerged chain. According to our idea, they are fragments from the margin of the separating blocks, the detachment of which is easily explicable in such zones of tectonic disturbances.

Immediately to the north in Europe are folded ranges of a still older mountain system which was thrown up between the Silurian and Devonian and now traverses Norway and Scotland. E. Suess called it the Caledonian System. Andrée[1] and Tilmann[2] have dealt with the question of the extension of this system of mountain folding into the “Kanadische Kaledoniden” (Termier), that is, into the Canadian Appalachians, which were folded already by Caledonian movements. Naturally the agreement is not prejudiced by the fact that this Caledonian folding in America was again affected by the Armorican folding described above, which only happened here in Europe in the Hohes Venn and the Ardennes, but not in the northern part of the continent. The portions of these Caledonian folds which have been in contact are to be sought for in the Scottish Highlands and Northern Ireland on one side, and in Newfoundland on the other.

In Europe, just north of the Caledonian System,

  1. K. Andrée, “Verschiedene Beiträge sur Geologie Kanadas,” Schriften d. Ges. z. Beförd. d. ges. Naturwiss. zu Marburg, 13, 7, p. 437. Marburg, 1914.
  2. N. Tilmann, “Die Struktur und tektonische Stellung der kanadischen Appalachen. Sitzber. d. Naturwiss., Abt. d. Niederrhein. Ges. f. Natur-. u. Heilkunde in Bonn, 1916.