Many Precambrian granulite facies
terrains experienced two regional
high-grade events, with the first one having occurred in the Neoarchaean and the subsequent overprints in the Palaeoproterozoic. Since structural and geochronological studies often are unable to discriminate between these two tectono-metamorphic events (D/M), we used the configuration of a composite
P–T path as a signature of two granulite facies metamorphisms. The path has a forked lightning shape, composed of two
high-
grade decompression cooling (DC) branches: a
higher-pressure (DC1) and a lower pressure (DC2) trajectory, which are connected by an isobaric heating (IH) path, indicating the
start of the second high-
grade metamorphism. This approach was used to distinguish different D/M events in the Central Zone of the Limpopo
high-
grade (HG)
terrain, which previously had been considered to mainly reflect evidence for a Palaeoproterozoic event (
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
2 Ga). We developed a method that allowed us to discriminate between two different HG events based on strong chemical heterogeneity of coexisting minerals in metapelitic gneisses. Using this method we have studied Al-rich gneisses from key geological structures in different parts of the Central Zone, for which we provided evidence for the first Neoarchaean HG event D2/M2 (
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
2.6 Ga), that is mostly reflected by DC1. Evidence for a subsequent Palaeoproterozoic HG tectono-metamorphic event, D3/M3 (
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
2 Ga) in the same rocks is reflected by both the IH and relatively low-pressure DC2 segments of a the composite
P–T path. Although all studied rock samples preserve records of both the HG metamorphic events, the D3/M3
strongly sheared gneisses contain lesser amounts of the D2/M2 relics compared to rocks less affected by shearing. The results of our studies and a review of published data allow a correct interpretation of
questionable isotopic ages and
structural data with the following conclusion: the CZ of the Limpopo Complex was subjected to three superimposed tectono-metamorphic events: the earliest D1/M1 (
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
3.33 Ga) is related to greenstone metamorphic conditions (
Kreissig et al., 2000), followed by two
high-
grade events that respectively occurred at
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
2.6 Ga (D2/M2) and
![not, vert, similar not, vert, similar](http://www.sciencedirect.com/scidirimg/entities/223c.gif)
2 Ga (D3/M3).