The area comprises portions of the Central and the Okahandja Lineament Zones of the Damara Orogen which are separated by the Okahandja Lineament, and rocks of the Abbabis Complex and of the Damara Sequence are exposed. The Abbabis Complex includes metamorphic rocks of sedimentary and intrusive origin, viz. quartzite, schist locally including pebbles, and marble, as well as the Ricksburg granite, a granodiorite, an augengneiss and orthoamphibolite. The Damara Sequence begins with gritty quartzite of the Etusis Formation of the Nosib Group. This is unconformably overlain by the Swakop Group. Rocks of the Ugab Subgroup are absent, and the succession begins with pebbly schist of the Chuos Formation which form, however, only two small outcrops. The Karibib Formation is well developed; it includes the basal Omusema Member, consisting of up to 500 m thick amphibolite derived from basaltic lava, and the overlying carbonate rocks known as the "Karibib marble". Because of intense plication, the thickness of the marble cannot be determined; it is, however, known to decrease considerably from north to south.