The Early Cretaceous and Miocene Peneplains of Nyasaland, and their Relation to the Rift Valley

Abstract

In that part of Central Africa lying to the west and south of Lake Nyasa various ancient peneplains have long been known (in (9)), but there has hitherto been available but little evidence whereby their relations to each other and to other more distant peneplains could be established. West and north-west of the lake, for example, there is the “4,000—foot” plateau, out of which rises the 7,000–8,000 ft. plateau of the Nyika and neighbouring highlands (see Fig. 1; also physical map in in (9)); and south of the lake, in Southern Nyasaland, the Kirk Mountains plateau (5,000 feet) overlooks the Shire Rift Valley from the west, whereas on the eastern side the eastward tilted Shire Highlands plateau is surmounted by the Zomba plateau (6,000 feet) and the Mlanje plateau (7,000 feet); the summit levels of the Mlanje Mountains, at 9,000–10,000 feet, probably indicate another ancient surface.