Page:The origin of continents and oceans - Wegener, tr. Skerl - 1924.djvu/98

72 rupture, has become most strongly curved by this process of movement; the inclusions of sima were squeezed out by it. The islands are basaltic, and one of them (Zawadowski Island) still shows volcanic activity. Moreover, according to F. Kühn, the late Tertiary Andean folding is absent on the whole chain of the South Antillean curve, whilst the more ancient folds are known in South Georgia, South Orkneys, etc. These peculiarities are readily explained by the displacement theory, for if the folding in South America and Graham Land was actually produced by the westerly drift of the blocks, it must have ceased in the South Antillean curve at the time when the latter remained stationary.

In this connection the Permo-Carboniferous glacial phenomena which are found everywhere on the southern continents could be adduced to prove the displacement theory, for they form—in a similar manner to the Old Red in the Northern hemisphere—the fragments of a single land-mass which can be explained much more easily by the displacement theory than by that of the submerged bridging-continents, because of their great distance apart. However, this phenomenon will be described in more detail in the, because it is first and foremost a question of climate.