the Dwyka Group

Glacial deposits of the Dwyka Group between Keetmanshoop and Mariental in southern Namibia have been reinvestigated for palaeontological remains and associated tuff horizons in an attempt to accurately date the deposits. SHRIMP-based dating of juvenile zircons from these tuff horizons provide ages which cumulate in the latest Carboniferous (Gzelian). The pycnoxylic woods Megaporoxylon scherziKrausel and Megaporoxylon kaokense Krausel are 'described in detail for the first time and are compared with similar permineralised woods from Gondwana. Based on previous fossil wood studies covering the rocks of the main Karoo Basin, these species occur onl y in the Dwyka and lower Ecca Groups in southern Africa and do not extend to the upper Ecca Group