Three major tectono-stratigraphic units are distinguished in the upper Black Nossob River area, east of Okahandja. The Ekuja-Otjihangwe Nappe Complex, which is the lowermost unit, is made up mainly of pre-Damara basement with a relatively thin cover of lower Damara Sequence metasedimentary and metavolcanic rocks. Most of the cover rocks are correlated with the Vaalgras Subgroup of the Southern Margin Thrust Belt, but in addition one outcrop of metasediments belonging to the Kudis Subgroup was also found. Furthermore, a unique succession of syntectonic metaconglomerate, marble, and minor schist, which has been named the Hochberg Formation, occurs just below the Hochberg Thrust, which separates the Ekuja-Otjihangwe Nappe Complex from the overlying Khomas Zone. The Khomas Zone is subdivided into two tectono-stratigraphic units, of which the Onjona-Vrolikheid Fold Complex is the lower unit and the Onyati Mountains Schist Belt is the upper unit. The Onjona-Vrolikheid Fold Complex is essentially composed of coarse-grained quartzites and marbles as well as some schists, all belonging to the lower Damara Sequence, but a few outcrops of basement gneiss were also found in the south. In addition ultramafic rocks fringe the Ekuja-Otjinhangwe Nappe Complex in the east, but tectonically they appear to occur at the base of the Khomas Zone. The Onyati Mountains Schist Belt consists of the Kuiseb Formation of the upper Damara Sequence, which is a very thick succession of pelitic, semi-pelitic and psammitic schists with some amphibolites, calc-silicates, and minor marble. Syntectonic granite-pegmatites have intruded the Kuiseb schists in the north.