The Brandberg West Formation of the Damara Sequence in the lower Ugab River area consists of a basal portion of interbedded siliciclastic and calcareous sediments, and an overlying sequence of blue-grey marbles. The sedimentary features preserved in the basal portion of the formation suggest accomulation by mass flow processes. This conclusion is . supported by the turbiditic character of the underlying and overlying siliciclastic formations. The blue-grey marbles are, however, hemipelagic deposits which accumulated in a periplatform environment.