Ngesikhathi se-Cenozoic umaka wolwandle waqala wehla usuka ezindaweni eziphakeme owazwakala ngesikhathi se-Cretaceous. Uchungechunge lwamagquma amaningi alandelanayo abheke ndawonye akheka ezindaweni eziningi ezingasogwini lakwaKZN. EThekwini lokhu kwakhiwa amagquma ase-Bluff nase-Berea. Ezindaweni eziningi ukuguguleka okujulile kwamagqunyana amadala kukhiphe (kuzale) umhlabathi obomvu ngokujulile obizwa ngokuthi i-Berea Red Sand.
| i-Berea red sand | i-Berea red sand 4x magnified |
Ezikhathini eziningi zamanje, ukwehla nokwenyuka komaka wolwandle kuqhubekile nokulungisa ugu lakwaKZN. Amagqunyana amasha asogwini aqukethe amatshe anomnotho afana ne-ilmenite, i-rutile ne-zircon, ambiwa e-Richards Bay.
The ilmenite and rutile are smelted to produce titanium metal and white pigments (mostly for paint). The zircon is used for glazing on tiles and pottery, and as a metal alloy.
Titanium and zirconium rich minerals are significantly denser than common sedimentary minerals. As a result they became locally concentrated through their movement by wind and water through gravitational separation. This explains the dark areas on the beach.
(Source: Fockema P D, 1986 – The heavy mineral deposits north of Richards Bay)
Ngesikhathi sokugcina sokuhamba kweqhwa eminyakeni eyizigidi eziyishumi nesishiyangalombili umhlaba bewubanda nomaka wolwandle bewungaphansi kunamanje ngamamitha angaphezu kwekhulu. Ugu belungasolwandle kunamanje nemifula emikhulu yasika izigodi ezijulile ezigudla ugu. Ngenkathi umhlaba ufudumala nomaka wolwandle ukhuphuka, lezizigodi zagcwaliswa udaka lwamachweba nezihlabathi ezigcwele amagobongo ezilwane zasolwandle. Kungalesisizathu amabhuloho amaningi agudla usebe adinga izisekelo ezijulile ukuze zithinte amadwala angaphansi aqinile.
Beach sands represent the weathered and eroded remnants of rocks found inland. KwaZulu-Natal beach sand is characteristically brownish in colour, consisting mainly of more resistant minerals such as quartz and feldspar. Of major economic importance, the sands also contain abundant quantities of the minerals ilmenite, rutile and zircon which are mined near Richards Bay for titanium and zirconium.
