Sulphide Re-Os geochronology links orogenesis, salt and Cu-Co ores in the Central African Copperbelt

Abstract

The origin of giant, sedimentary rock-hosted copper-cobalt (Cu-Co) provinces remains contentious, in part due to the lack of precise and reliable ages for mineralisation. As such, no consensus has been reached on the genetic model for ore formation, and the relationships between tectonism, palaeo-fluid circulation and mineralisation. Here, we link the timing of Cu-Co mineralisation in the Central African Copperbelt to compressional tectonics during the Lufilian Orogeny by using new ca. 609–473 Ma ages given by rhenium-osmium (Re-Os) isotope data for individual Cu-Co sulphides (carrolite and bornite) from the Cu-Co Kamoto deposit. The initial Os isotope composition of carrolite is compatible with the leaching of Os and Cu(-Co) from Mesoproterozoic Cu sulphide deposits hosted in fertile basement. In contrast, the ca. 473 Ma Cu-Au mineralisation stage, which is coeval with late- to post-compressional deformation, may be a distal expression of fluid flow and heat transfer caused by magmatic intrusions in the core of the collisional orogen. The Re-Os ages support a model for mineralisation driven by evaporite dissolution and percolation of large volumes of dense brines in the Katangan Basin during the Lufilian Orogeny.

Genetic relationship between hydrocarbon system evolution and Carlin-type gold mineralization: Insights from ReOs pyrobitumen and pyrite geochronology in the Nanpanjiang Basin, South China

“…These solutions yielded values of 0.16083 ± 0.00006 for 50 pg aliquot of DROsS and 0.5990 ± 0.0008 (1SD, n = 5) for a 125 pg aliquot of the Re standard, both of which are in good agreement with those previously reported at Durham University (e.g., Saintilan et al (2018) and references therein). The Re-Os ages were determined using the 187 Re/ 188 Os and 187 Os/ 188 Os ratios together with their total 2σ uncertainty and 13 associated error correlation, rho, and with the 187 Re decay constant of 1.666x10 -11 a -1 (Smoliar et al, 1996), via the program Isoplot v. 4.15 (Ludwig, 2008).…”

Metal-rich organic matter and hot continental passive margin: drivers for Devonian copper-cobalt-germanium mineralization in dolomitized reef-bearing carbonate platform

“…Here, we use the new method of Re-Os isotope geochemistry and isochron regression applied to mineral separates of individual sulfide species co-existing in single hand samples (carrollite, bornite, pyrite in this paragenetic order; Fig. 2b, Electronic Supplementary Materials-ESM Table 1) but analyzed separately (Saintilan et al 2018(Saintilan et al , 2020. The δ 34 S signatures of these mineral separates were constrained by standard techniques whereas variations in the δ 98/95 Mo of purified Mo fractions of each sulfide species were determined by multicollector inductively coupled mass spectrometry.…”

Vanadium Pentaoksida (V2O5) : Termodinamika Molecular dan Interaksi Ion dalam Larutan

“…Ketika pelarut diuapkan, ion tidak ikut menguap, tetapi tetap berada di dalam larutan yang tertinggal , dan bila sudah cukup pekat terjadilah nukleasi (154)(155)(156) dan mengkristal menjadi senyawa ionic. Proses ini dapat dinamakan dengan cara pembentukan mineral evaporit (157)(158)(159)(160)(161)(162). Pada vanadium pentaoksida memiliki titik lebur (163)(164)(165)(166)…”