Late cenozoic shallow marine diamond placers off the northern Sperrgebiet, Namibia

Small scale diver-assisted diamond mining has taken place since 1990 in the shallow marin (<30 m water depth) portions of Mining Licence 45 (Elizabeth Bay) between Halifax Island and Elizabeth Bay along the southwestern coast of Namibia. These operations in the northern part off the coast of the Sperrgebiet have produced almost 400,000 carats over a period of 17 years. Although sparse records remain from the early days, sufficient data from various sources were collected, collated and summarised to make meaningful observations. From historic and current diamond diving records, 4 submarine areas which have yielded high returns were described in terms of their geomorphology, sedimentology and diamond occurrence. Using detailed geophysical survey data (Sidescan Sonar and Multi-beam Bathymetry), the deposition of diamonds at these sites were modelled in GIS-based reconstructions. The diamond size frequency distribution (SFO) of the Shallow Marine (0 to -30 m) deposits in the study area is similar to the proximal aeolian deposit mined on land at Elizabeth Bay and the deeper Midwater (-30 to -70 m depth) deposits situated southwest of the study area.

Grantor dc:publisher.institution

Department of Geological Sciences

Year dc:date.issued

2008

Author dc:creator

• Oelofsen, André

Advisor dc:contributor.advisor

• Compton, John

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/11427/4215

OAI identifier oai:identifier

oai:open.uct.ac.za:11427/4215