Metallogenic characteristics and enrichment mechanism of cobalt deposits in the Central African Cu-Co metllogenic belt
The Zambian-Congo(DRC)copper cobalt metllogenic belt in the Central Africa is a large-scale and high Cu-Co graded stratabound copper-cobalt ore belt in the world.It is famous for having large and super-large copper-cobalt deposits and numerous world-class copper-cobalt mines.Many Chinese enterprises have carried out copper-cobalt deposit development in Zambia and Congo(DRC).The supernormal enrichment of cobalt is subject to a debate between the syngenetic origin and the late-stage reworking origin.Previous researches show that the formations of cobalt deposits underwent diagenesis and mineralization during the rifting period(880-735 Ma)and the mineralization during the orogeny period(530～490 Ma),which are respectively consistent with the formation,development and evolution of the Neoproterozoic Katanga sedimentary basin and the Lufilian orogeny.The formations of syngenetic sedimentary cobalt deposits and hydrothermaly reformed cobalt-rich deposits were closely related to the sedimentary environment and the multi-stage mineralization.It is considered that the supernormal enrichment of cobalt is related to the multi-stage cycling process through migration-enrichment-precipitation of metal-rich ore-forming fluids which were formed through the metasomatism of basement rocks(ores)by brine in depth.Cobalt generally intergrew with or is associated with copper.Cobalt-bearing minerals include carrollite,skutterudite,linnaeite,cobalt pyrite,heterogenite,erythrite,and spherocobaltite.Sedimentary cobalt deposits are developed in Zambia,with relatively low cobalt contents.Hydrothermally reworked cobalt deposits are relatively developed in the Democratic Republic of Congo,and they are of the sedimentary-hydrothermally reworked type of cobalt deposits.There are obvious oxidation zone and primary zone of cobalt deposits,with depth of up to 300m for the oxidation zone locally.Supergene oxidation often leads to the cobalt mineralization and enrichment.At present,in response to the overall low level of geological researches on cobalt-rich deposits in the area,it is proposed to strengthen the in-depth detailed researches on the source of ore-forming materials,ore-forming environment,especially the supernormal enrichment mechanism of copper and cobalt of primary copper-cobalt deposits.
cobalt rich depositmetallogenic characteristicsenrichment mechanismCu-Co ore belt in the Central African
NETL
NSTL
万方数据
维普
