Project title: Halokinetic Structure in the Kipushi-Kalindi area (Zambia-DRC) and Comparison of the Paragenetic Sequence of Alteration and Mineralization in the Kipushi-Kalindi area with the Paragenetic Sequence at Kakanda (DRC)
Researcher: Helen Twigg
This research project investigates the role of evaporites in the formation of base metal minerals in the Central African Copperbelt, a polymetallic belt which contains sediment-hosted stratiform base metal deposits. It has long been recognised that evaporites can influence the formation of mineral deposits in multiple ways; residual and dissolution brines provide transport mediums, evaporite beds, and diapirs form impermeable barriers and influence geothermal gradients affecting fluid flow. The influence of holokinetic salt on basin morphology and the development of stratigraphic and structural traps for stratiform mineralization through halokinesis has not been well investigated in the Central African Copperbelt. The Kalindi-Phoenix-Kipushi (KPK) study area provides an ideal location to investigate this problem. Field work will involve collection of lithological, structural, mineralization and alteration data. These will be utilised in addition to drillhole, outcrop, and airborne geophysical data to construct a structural and lithofacies model of the KPK study area. The model will be created using Leapfrog and Move software and will provide an interpretation of changing sub-basin architecture during deposition of the Katangan Supergroup sediments and subsequent basin inversion. The paragenesis of alteration and mineralization in the Nguba Group sedimentary host rocks at KPK and in the older Roan Group host rocks at Kakanda will be determined using petrological, geochemical, and isotopic analysis methods. Results will be compared to paragenetic studies of Kipushi and Kipushi Est, in the Democratic Republic of Congo (DRC) and Kakanda to other Roan Group-hosted deposits in the DRC. The ultimate aim of the project is to determine how the paragenetic sequences of the different mineral deposit types in the CACB are linked to evaporite (and residual brine) formation, brine circulation, halokinesis, changing temperature and salinity regimes, and evaporite dissolution.