Sediment-hosted ore deposits tour blog Part 3a

Otjikoto Gold Mine, B2Gold Corp, Namibia Geology and mineralization: Otjikoto and recently discovered Wolfshaag deposit are part of a shear-zone hosted orogenic gold system. Host rocks are pelitic schists and marbles of the Okanguarri Fm. (also part of the Damara Supergroup, at a similar stratigraphic position as the Navachab gold deposit). Hosted in an overturned anticline, structures related tor S-folds related to refolding during D2 of the Damara Orogeny, played a part in creating zones later exploited by D3 shearing to create large zones of albitization and formation of sheeted magnetite-pyrite-carbonate-quartz veinlets that carried gold. There is an overprinting high temperature garnet-pyrrhotite event. Later stages of deformation resulted in remobilization of gold as free gold, making for excellent recovery (more than 98.5%!) from a combined gravity and elution circuit. The region is covered by extensive calcrete sequences, which makes one wonder as to how many undiscovered gold deposits are yet to be found in the Damara orogen! #KFFellows 


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