West and transported so far westwards at least as the 18th meridian. With the continental disruption hypothesis in mind, could they not possibly have been carried much further westwards still?”
We find further agreement, as already mentioned, in the directions of the ancient folds which traverse the whole of these great gneiss plateaus. For Africa, we can refer to the map taken from Lemoine, given in Fig. 8.[1]
_-_figure_08.jpg)
Fig. 8.—Trend lines in Africa, after Lemoine.
It was prepared for other purposes, and therefore does not show very clearly the facts which we need; nevertheless, it does show them. There are two more or less distinct chief directions of strike in the gneiss massive of the African continent. The older north-easterly strike predominates in the Sudan, and is to be observed in the straight, similarly directed upper course of the Niger, as far as the Cameroons. It cuts the coast at an angle of about 45°. South of
- ↑ P. Lemoine, “Afrique occidentale,” Handb. d. Regionalen Geologie, vol. vii, 6a, Part 14, p. 57. Heidelberg, 1913.
