Shrimp U-Pb zircon geochronology of the Hurungwe granite northwest Zimbabwe: Age constraints on the timing of the Magondi orogeny and implications for the correlation between the Kheis and Magondi Belts

This paper presents new U-Pb (SHRIMP) data for zircons from the late syn-kinematic Hurungwe granite in the internal zone of the Magondi Belt northwest Zimbabwe. The Concordia age of 1997.5 ± 2.6 Ma obtained on magmatic zircons from the Hurungwe granite is interpreted as the crystallisation age of the intrusion. These new data provide minimum age constraints on both the contractional stage of the Magondi orogeny and the deposition of the Piriwiri Group rocks into which the Hurungwe granite is intrusive. Based on the new data, the minimum age of the Magondi orogeny is 70 Ma older than the, currently constrained, maximum age of deformation and metamorphism in the Kheis Belt of South Africa, suggesting that models which link these two fold and thrust belts as coeval components of the same Palaeoproterozoic orogen are no longer valid.