Arid and semi-arid areas are lacking in fossils for the reconstruction of the Quaternary climate. Therefore, sediments from ephemeral rivers are a welcome climatic archive in Namibia. Restrictions concerning the palaeoclimatic evidence lie in the fact that the sediments examined usually reflect the climate of the upper reaches of the rivers rather than the local climate. The upper reaches may belong to a different climatic zone or (damp) altitudinal zone of vegetation. In order to rule out such allochthonous influences in the study of the climatic history of the escarpments between the edge of the Namib Desert and the savannah, research is limited to sediments in basins and valley floors which are not subject to such influences. Research in the Opuwo basin has extended knowledge of the recent Quaternary climatic history of northern Namibia into the period since ca. 60 ka. The sedimentation of the basin floor pediments began with the deposition of fluvial sands. From ca. 55 ka, desert loess was blown in the course of aridification, but this was washed away from the pediments towards the centre of the basin by ca. 45 ka. Surface runoff was sometimes strong enough to transport gravels and sands. Thus geomorphological activity in this period also differed from the drier period which set in around 45 ka. It was characterised by the exclusive sedimentation of desert loess, even on the pediments at the basin's rim. There are a total of three cambic regosol soil formation phases. However, as there are no indications of new clay formation or eluviation the climate can only have been slightly more humid during their formation.
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