A magmatic age and four successive metamorphic events recorded in zircons from a single meta-anorthosite sample in the Central Zone of the Limpopo Belt, South Africa
Ion microprobe U–Th–Pb analyses combined with cathodoluminescence imaging of zircons from a meta-anorthosite from the Central Zone of the Limpopo Belt record five distinct events. The most concordant ages of cores of zircon yielded a weighted mean 207Pb/206Pb age of 3344 ± 3.6 Ma, representing the protolith age. The unzoned overgrowths yielded four discrete groups with weighted mean 207Pb/206Pb ages of 3150 ± 15 Ma, 2614 ± 4 Ma, 2488 ± 22 Ma and 2009 ± 28 Ma, representing four possible metamorphic events in the Central Zone. This is the first time that a succession of several metamorphic events has been demonstrated in a single rock-type from the Limpopo Belt.
