Nepheline-bearing Lavas and Intrusive Rocks from South of the Zambezi River, with a Note on an Outcrop of Karroo Lavas in the Buzi Valley, Portuguese East Africa

Abstract

In reviewing the tectonic features of a portion of Portuguese East Africa, south of the Zambezi, one of the present writers alone (2), and also in conjunction with Capt. R. C. Wilson (1), advanced the view that the surface topography had to some extent been affected by the same movements which were associated farther north with the Rift Zone period of Eastern Africa. This opinion was arrived at from the consideration of the physiography, the observation of definite faulting in places, especially in western Sheringoma on an extension of the Nyasa-Shire line, and also of volcanic occurrences elsewhere in significant positions.