U–Pb and Hf-isotope analyses of zircon from the Kundelungu Kimberlites, D.R. Congo: Implications for crustal evolution

摘要: Abstract The Gungwania and Talala kimberlitic pipes on the Kundelungu Plateau (Katanga, SE Congo) have been used as drillholes, to obtain crustal zircons for a study of evolution in region constrain age basement sedimentary provenance Katangan Supergroup. Two hundred twenty-nine zircon grains were analysed U–Pb ages Hf-isotope compositions. Juvenile Mesoarchean (∼3.4–3.3 Ga) crust underwent recycling during Neoarchean Paleoproterozoic time. event involved little production juvenile crust, this was recycled Mesoproterozoic Neoproterozoic Both characterised by bimodal magmatism reflecting extension, linked with break up Rodinia opening basin, development crust. Detailed studies external morphology different groups suggest that beneath is predominantly age; other populations may be derived from sediments. absence any younger than 560 Ma supports deposition Biano Subgroup, which hosts kimberlites, Pan-African Lufilian orogeny. Archean Congo Zimbabwe cratons, Ubendian Belt (Bangweulu Block), Paleo-to-Mesoproterozoic Irumide Belt, Kibaran Choma Kalomo Block all contributed material sediments