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We carried out SHRIMP zircon U-Pb dating on A-type granitic intrusions from the Namaqua-Natal Province, South Africa, Sverdrupfjella, western Dronning Maud Land, Antarctica and the Nampula Province of northern Mozambique. Zircon grains in these granitic rocks are typically elongated and oscillatory zoned, suggesting magmatic origins. Zircons from the granitoid intrusions analyzed in this study suggest ∼1025–1100 Ma ages, which confirm widespread Mesoproterozoic A-type granitic magmatism in the Namaqua-Natal (South Africa), Maud (Antarctica) and Mozambique metamorphic terrains. No older inherited (e.g., ∼2500 Ma Achean basement or ∼1200 Ma island arc magmatism in northern Natal) zircon grains were seen. Four plutons from the Natal Belt (Mvoti Pluton, Glendale Pluton, Kwalembe Pluton, Ntimbankulu Pluton) display 1050–1040 Ma ages, whereas the Nthlimbitwa Pluton in northern Natal indicates older 1090–1080 Ma ages. A sample from Sverdrupfjella, Antarctica has ∼1091 Ma old zircons along with ∼530 Ma metamorphic rims. Similarly, four samples analysed from the Nampula Province of Mozambique suggest crystallization ages of ∼1060–1090 Ma but also show significant discordance with two samples showing younger ∼550 Ma overgrowths. None of the Natal samples show any younger overgrowths. A single sample from southwestern Namaqualand yielded an age of ∼1033 Ma.Currently available chronological data suggest magmatism took place in the Namaqua-Natal-Maud-Mozambique (NNMM) belt between ∼1025 Ma and ∼1100 Ma with two broad phases between ∼1060–1020 Ma and 1100–1070 Ma respectively, with peaks at between ∼1030–1040 Ma and ∼1070–1090 Ma. The age data from the granitic intrusions from Namaqualand, combined with those from Natal, Antarctica and Mozambique suggest a crude spatial-age relationship with the older >1070 Ma ages being largely restricted close to the eastern and western margins of the Kalahari Craton in northern Natal, Mozambique, Namaqualand and WDML Antarctica whereas the younger

The Saharan Metacraton is a poorly known tract of pre-Neoproterozoic continental crust that occupies the area between the juvenile Arabian Nubian Shield, in the east, and the Tuareg Shield to the west. Neoproterozoic orogenesis (i.e. Ouban guides and East African orogenies) affect the west, the south and the east of the metacraton, respectively, which led to deformation, emplacement of igneous bodies, and localised episodes of rift-related magamatism. Details about interior regions of the Saharan Metacraton are poorly known, with much of it covered by Phanerozoic rocks. The basement outcrops in Sudan, Chad, Algeria and Libya have been the subject of few modern geochronological studies. Here we present results from the first zircon geochronology and in-situ zircon hafnium isotope investigations from both the Sudanese Butana and central Chad. The terranes in Butana, formed to the east of pre-Neoproterozoic continental crust of the Saharan Metacraton, with the oldest juvenile magmatism (ƐHf(t) of +4.89 to +7.89) at ca. 839 Ma, followed by subsequent magmatism at ca. 787 Ma. The ca. 787 Ma event (seen elsewhere in the East African Orogen) is interpreted to represent volcanic-arc collision and accretion with the kernel of the Saharan Metacraton. The ca. 839 Ma magmatism is contemporaneous with the accretion of the Tonian (ca. 850 Ma) arc terranes of the Arabian Nubian Shield and marks subduction to the east of the Saharan Metacraton. The magmatic history of the Ouaddaï region in Chad begins in the late Mesoproterozoic, with localised rifting, resulting in the emplacement of juvenile granites (ca. 1030 Ma). The Cryogenian and Ediacaran in the Saharan Metacraton reveal a complicated history of magmatism and deformation. Age data from Chad show the emplacement of granites (from melting of Mesoproterozoic crust: ƐHf(t) = +2.04 and −4.07) at ca. 665–654 Ma, coeval with the main East African Orogeny and accretion of the other ANS terranes to the Saharan Metacraton at ca. 650–580 Ma. The youngest tectonothermal event within the Saharan Metacraton is recorded by emplacement of granites between 580 and 550 Ma (ƐHf(t) values of −17 to −31) in southern Chad. Refereed/Peer-reviewed