Minerals Report - International Seabed Authority

The combined interaction of the fluvial, marine and aeolian
sedimentary environments together with arid zone weathering processes
along the Namibian coastline essentially acts as an enormous “sediment
transport conveyor” breaking down, recycling and transporting large
volumes of sediment to the north (Figure 3) [19]. Ultimately, much of this
material is incorporated into the coastal tract of the Namib Sand Sea where
the initial diamond discovery was made, and diamonds were literally
picked up from the desert floor in such quantities that Stauch is reputed to
have carried on prospecting in the desert moonlight.
NSS
L
NDB
ATC
LS
100 Km
Figure 3. Principal elements of the “Sediment Transport Conveyor” produced by
interaction of sedimentary environments. OR = Orange River, LS = long shore littoral
transport, ATC = aeolian transport corridor(s) feeding the Namib Sand Sea (NSS) via the
Namib Deflation Basin (NDB) which starts at Chameis, approximately 100 km north of
Oranjemund. L= Luderitz
2.2 Physical character of the marine onshore and offshore diamond
deposits
2.2.1 Onshore littoral systems and shallow-water ore bodies
The coastal marine deposits to the north of the Orange River form a
wedge of predominantly coarse clastic gravels tapering to the north over
110 km in the prevailing direction of the long shore littoral current.
Recently, sedimentological studies at NAMDEB have provided new
insights into the spatial changes in the architecture of the littoral ore body
(Figure 4). In the south, in the immediate vicinity of the Orange River,
high-energy wave-dominated littoral processes have resulted in the
OR
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