To the Pliocene period the marine deposits of the Sahel of Algiers and of the Sahel Jijelli must be attributed; also the lacustrine marls and limestone of the basin of Constantine, and the ancient alluviums of the basins and depressions which bear no relation to the existing valleys.
The recent deposits of the Transvaal may be considered to be insignificant. They include the gravels and alluviums of the present streams and the almost ubiquitous red sand of aeolian origin.
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