Abstract
The 450 km long and 40-50 km wide Namaqualand pegmatite belt, synonymous with the Orange River pegmatite belt (ORPB), consists of > 30 000 individual pegmatites that intruded the Namaqua Sector of the Mesoproterozoic Namaqua-Natal Metamorphic Province (NNMP) in Southern Africa at ca. 1 Ga. The central part of the belt is characterised by the occurrence of NYF pegmatites, classified as mineralised, herewith referred to as complex (Witkop, Koegab, Sidi-Barrani) and regular, referred to as simple (WD-S-, CD-S-, ED-S) pegmatites located in the western, central and eastern domains of the Kakamas Domain. The classification of the pegmatites in this study is based on their field appearance including size, zoning and proportion of rare element-bearing minerals. Complex pegmatites are enriched in REE-U-Th-rich mineral phases, are large in scale in the field (up to tens of meter’s thick) and show a heterogeneous texture. Simple pegmatites are those that contain minor concentrations of REE-U-Th-rich mineral phases, are of smaller scale (up to few meter-thick) compared to complex pegmatites and mostly show a relatively homogeneous texture...
M.Sc. (Geology)