The Pan-African belt in central Africa has benefited from the many petrographic, structural, and geochronological studies in the recent years that have improved our understanding of the belt. However, those studies have also produced various and often divergent evolutionary models for the belt, some of which do not even involve well-defined cratons. Following a review of the available data in Cameroon, we propose a model of continent–continent collision that involved the Congo craton and the north-central Cameroon active margin showing Archean to Paleoproterozoic inheritances. This model is based, among others, on (i) the prominent role of the Congo craton as demonstrated by the regional extension of external nappes on its northern edge and the concomitant exhumation of the 620 Ma granulitic rocks believed to have formed at the root of the collision zone, and (ii) the late development of a strike slip fault system in central Cameroon as the result of horizontal movement following the multistage collision. In the general framework of the Pan-Africano – Brasiliano belt, a comparison of the kinematic and age of deformation north of the Congo craton to that east of the West African craton, suggests that the overall tectonic evolution of the mobile domain between both cratons is controlled by their relative motion.

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The Congo (CC) and the São Francisco (SFC) cratons were joined at about 2.05 Ga; northern parts of Palaeoproterozoic basement subsequently underwent extension at about 1 Ga, forming intracratonic basins. Neoproterozoic metasedimentary rocks in these basins yield detrital zircons as young as 630 Ma. The Brasiliano and Pan-African (c. 620–580 Ma) assembly of West Gondwana extensively altered this system. The Sergipano domain occurs north of the SFC, and the comparable Yaoundé domain occurs north of the CC. Crust north of the Sergipano domain comprises the Pernambuco–Alagoas (PEAL) domain. The NE–SW-striking Tcholliré–Banyo fault in Cameroon may extend southwestwards between the PEAL and Sergipano domains, defining northern limits of abundant SFC/CC basement. The Adamawa–Yadé domain in Africa does not appear to extend into Brazil. The Transverse domain of Brazil is a collage of Palaeoproterozoic crustal blocks, the 1.0 Ga Cariris Velhos orogen (CVO), late Neoproterozoic basins, and Brasiliano granites. The CVO extends ENE for more than 700 km in Brazil, but eastern continuation into Africa has not been identified. North of the Transverse domain contiguous c. 2.15 Ga gneisses comprise basement of Rio Grande do Norte and Ceará domains, which continue eastwards into western Nigeria and western Sahara.

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The Nagoundéré Pan-African granitoids in Central North Cameroon belong to a regional-scale massif, which is referred to as the Adamawa-Yade batholith. The granites were emplaced into a ca. 2.1 Ga remobilised basement composed of metasedimentary and meta-igneous rocks that later underwent medium-to high-grade Pan-African metamorphism. The granitoids comprise three groups: the hornblende-biotite granitoids (HBGs), the biotite ± muscovite granitoids (BMGs), and the biotite granitoids (BGs). New Th-UPb monazite data on the BMGs and BGs confirm their late Neoproterozoic emplacement age (ca. 615 ± 27 Ma for the BMGs and ca. 575 Ma for the BGs) during the time interval of the regional tectono-metamorphic event in North Cameroon. The BMGs also show the presence of ca. 926 Ma inheritances, suggesting an early Neoproterozoic component in their protolith.The HBGs are characterized by high Ba-Sr, and low K 2 O/Na 2 O ratios. They show fairly fractionated REE patterns (La N /Yb N 6-22) with no Eu anomalies. The BMGs are characterized by higher K 2 O/Na 2 O and Rb/Sr ratios. They are more REE-fractionated (La N /Yb N = 17-168) with strong negative Eu anomalies (Eu/Eu * = 0.2-0.5). The BGs are characterized by high SiO 2 with K 2 O/ Na 2 O > 1. They show moderated fractionated REE patterns (La N /Yb N = 11-37) with strong Eu negative anomalies (Eu/Eu * = 0.2-0.8) and flat HREE features (Gd N /Yb N = 1.5-2.2). In Primitive Mantle-normalized multi-element diagrams, the patterns of all rocks show enrichment in LILE relative to HFSE and display negative Nb-Ta and Ti anomalies. All the granitoids belong to high-K calcalkaline suites and have an I-type signature.Major and trace element data of the HBGs are consistent with differentiation of a mafic magma from an enriched subcontinental lithospheric mantle, with possible crustal assimilation. In contrast, the high Th content, the LREE-enrichment, and the presence of inherited monazite suggest that the BGs and BMGs were derived from melting of the middle continental crust. Structural and petrochemical data indicate that these granitoids were emplaced in both syn-to post-collision tectonic settings.

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