Stable isotope and geochemical studies in the role of early diagenesis in ore formation, Konkola Basin, Zambian copper belt

Petrography and geochemistry of the Shilu Fe–Co–Cu ore district, South China: Implications for the origin of a Neoproterozoic BIF system

“…S CDT values ranging from +11.1 to 17.5‰ (average +15.97‰; Xu et al, 2009), comparable to a mean δ 34 S value of +17.5‰ ± 3‰ for Neoproterozoic seawater at the time of deposition of the Shilu Group, but distinctly different from those of the Zambian Copperbelt (El Desouky et al, 2010;Sweeney et al, 1986). Nevertheless, the previous study (Xu et al, 2013) has indicated that the tectonic, metamorphic and hydrothermal reworking which most likely was related to the multistage orogenies in South China has significantly modified the Shilu district resulting in enrichment and upgrading of Fe-and Co-Cu ores and secondary mineralization.…”

“…The Zambian Copperbelt occurs within a rift-related, Neproterozoic metasedimentary sequence of greenschist facies which unconformably overlies granites and other rocks of the basement complex, and is characterized by disseminated sulfide ores chiefly comprising chalcopyrite, bornite, and chalcocite with ore-grade carrollite, cobaltiferous pyrite, and cobalt pentlandite in some deposits (Annels et al, 1983;Selley et al, 2005;Sweeney et al, 1986). Various genetic models such as epigenetic-magmatic to syn-sedimentary, diagenetic, and epigenetic-syn-orogenic have been proposed for the source of metals, origin and physiochemical nature of transporting fluids, sulfide precipitation mechanisms, and timing of mineralization in the Zambian Copper belt (El Desouky et al, 2010 and references therein).…”

Metallogenesis of the Nkana copper–cobalt South Orebody, Zambia

“…The genesis of such mineralization is interpreted to have taken place during diagenesis of the host sediments (Bartholomé et al, 1971(Bartholomé et al, , 1972Bartholomé, 1974;Dimanche, 1974;Sweeney et al, 1986;Unrug, 1988;Binda, 1989, 1994;Cailteux et al, 2005;Muchez et al, 2008). Barra et al (2004) and Barra and Broughton (unpublished data, in Selley et al, 2005) used ReOs isotopes to demonstrate the occurrence of an episode of diagenetic mineralization in the Zambian Copperbelt.…”

Multiphase origin of the Cu–Co ore deposits in the western part of the Lufilian fold-and-thrust belt, Katanga (Democratic Republic of Congo)

“…This sulphide precipitated at temperatures between 20 and 60°C and at near-neutral pH due to bacteriogenic processes (cf. Bartholomé, 1974;Fleischer et al, 1976;Sweeney et al, 1986Sweeney et al, , 1991Okitaudji, 1992Okitaudji, , 2001.…”

“…The observation that also large pores are partly cemented by this non-luminescent dolomite generation favours a mineralization under shallow burial conditions. Also Sweeney et al (1986) and Binda (1989, 1994) propose that the bulk of the sulphides formed before appreciable burial of the sediments.…”