Geologica Belgica

1374-8505

 

Impact factor: 1.041 (2012)

since 05 February 2011 :
View(s): 348 (5 ULg)
Download(s): 3973 (8 ULg)
print
Maarten HAEST & Philippe MUCHEZ

Stratiform and vein-type deposits in the Pan-African Orogen in Central and Southern Africa: evidence for multiphase mineralisation

Article Open Access

Attached document(s)

Mots-clés : Central and Southern Africa, Neoproterozoic mineralisations, Pan-African Orogen, Stratiform Cu-Co ore deposits, Vein-type Zn-Cu-Pb-Ag deposits

Abstract

Stratiform deposits in the Pan-African Orogen are of the Cu-Co type and are restricted to carbonates and siliciclastic sediments that are stratigraphically close above the basement. The stratiform Cu-Co deposits formed during early diagenesis (possibly around 820 Ma) and during late diagenesis/metamorphism and the Pan-African Orogeny (~580 to ~520 Ma). The early diagenetic Cu-Co sulphides were partly remobilised into the second stratabound Cu-Co mineralisation, with precipitation of Cu-Co sulphides in nodules, veins and as breccia cements.

Vein-type Cu-Pb-Zn mineralisation occurs at two distinct levels, higher in the stratigraphy. The lower level vein-type deposits occur in dolomite and are dominantly of the Zn-Cu type. The higher level vein-type deposits occur at the contact between dolomite and sandstone and are dominated by massive Cu. The Cu-dominated deposits that have been dated, developed during the waning stage of the Pan-African Orogeny (~530 to ~500 Ma). The Zn-dominated deposits for which a mineralisation age has been established, formed after the Pan-African Orogeny. Some of these vein-type mineralisation have been remobilised after their formation, with the precipitation of massive Cu(-Ag) sulphides.

To cite this article

Maarten HAEST & Philippe MUCHEZ, «Stratiform and vein-type deposits in the Pan-African Orogen in Central and Southern Africa: evidence for multiphase mineralisation», Geologica Belgica [En ligne], volume 14 (2011), number 1-2, 23-44 URL : http://popups.ulg.ac.be/1374-8505/index.php?id=3188.

About: Maarten HAEST

Centre of Excellence for 3D Mineral Mapping, Earth Science and Resource Engineering, CSIRO, Dick Perry Avenue 26, 6102 Kensington, WA, Australia

About: Philippe MUCHEZ

Geodynamics and Geofluids Research Group, Department of Earth and Environmental Sciences, K.U.Leuven, Celestijnenlaan 200E, B-3001 Heverlee, Belgium