The Abra deposit: a breccia-pipe polymetallic mineral system in the Edmund Basin, Capricorn Orogen: implications for mineral exploration.

The deposit is a blind, stratabound sedimentary-rock hosted Fe-Pb-Zn- Ba-Cu(-Au-Ag-Bi-W) deposit located within the easterly trending Jillawarra rift sub-basin of the Mesoproterozoic Edmund Basin in Western Australia. The deposit is in the exploration stage and is estimated to contain 93 000 000 t of ore grading 4% Pb and 10 g/t Ag and 14 000 000 t at 0.62% Cu and 0.5 g/t Ag. The mineral system is characterised by several overprinting phases of hydrothermal activity from several stages of brecciation and fluidisation, barite and sulphide veining to barren low-temperature chalcedonic veining. Hydrothermal alteration minerals include multi-stage quartz, chlorite, prehnite, Fe-rich carbonate and albite. A preliminary genetic model is presented which indicates that there may be several hydrothermal breccia pipes each of which may be associated with distal haematite-barite chemical sediments and enhancing the prospectivity of the basin.
The deposit is a blind, stratabound sedimentary-rock hosted Fe-Pb-Zn- Ba-Cu(-Au-Ag-Bi-W) deposit located within the easterly trending Jillawarra rift sub-basin of the Mesoproterozoic Edmund Basin in Western Australia. The deposit is in the exploration stage and is estimated to contain 93 000 000 t of ore grading 4% Pb and 10 g/t Ag and 14 000 000 t at 0.62% Cu and 0.5 g/t Ag. The mineral system is characterised by several overprinting phases of hydrothermal activity from several stages of brecciation and fluidisation, barite and sulphide veining to barren low-temperature chalcedonic veining. Hydrothermal alteration minerals include multi-stage quartz, chlorite, prehnite, Fe-rich carbonate and albite. A preliminary genetic model is presented which indicates that there may be several hydrothermal breccia pipes each of which may be associated with distal haematite-barite chemical sediments and enhancing the prospectivity of the basin.