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Linte region, located within the Adamawa-Yade domain of the Central African Fold Belt (CAFB), is associated with the Pan-African orogeny in Cameroon. Magmatic (granular texture and suborientation of euhedral to subhedral feldspar crystals), sub-magmatic (intragranular fractures filled with quartz), and mostly solid-state (internal deformation, exsolution, and dynamic and static recrystallization) microstructures indicate that magmatic and metamorphic rocks of the Linte area were subjected to analogous tectonic manifestations during the Pan-African orogeny. Magmatic, sub-magmatic, and solid-state microstructural analyses combined with the existing age record reveal three phases of local deformation, namely Dn, Dn+1, and Dn+2, which can be correlated with regional D1 to D4 deformation phases of the CAFB. The Dn (ca. 660–600 Ma) marks the crystallization phase accompanied by magmatic and sub-magmatic microstructures. It is related to the regional D1-D2 deformation. The Dn+1 (ca. 600 Ma) represents a compressive tectonic setting related to the regional D3. The Dn+2 (ca. 598 Ma), initiated during D3, represents a transpressive tectonic combined with brittle deformation, and marked by sinistral and dextral shearings episodes, grading into the regional D4 stage. Collectively, microstructures recorded in the Linte igneous rocks can be correlated with the regional tectonic events, including crustal thickening, and successively sinistral wrench and regional dextral shear movements during the Pan-African orogeny in Cameroon. [ABSTRACT FROM AUTHOR]

The geological evolution of the Central African Fold Belt (CAFB) remains debated. The granitoids, orthogneisses and granitic veins from the Goa-Mandja area (Adamawa-Yade domain) are considered to constrain this belt. These rocks are consistent with late-D 2 regional emplacement and synchronous with the magmatism at ~600 Ma within the CAFB in Cameroon and its extension into northeastern Brazil, as the zircon U Pb dating points to 603–598 Ma crystallization ages. Analytical data reveal slightly elevated δ18O zrn (6.45–7.17‰) and δ18O WR (8.20–8.61‰), moderate to high SiO 2 (59.70–77.23 wt%), low MgO (0.07–2.77 wt%), Cr (0.29–55.12 ppm), Ni (0.45–33.6 ppm), V (1.52–116.62 ppm) and Mg# (0.02–0.36) contents, indicating crustal origin. The low to medium 87Sr/86Sr i (0.703328–0.722670) and positive to negative ε Nd(t) (+5.7 to −9.9), coupled with the diversity of Nd model ages (T DM2) support the heterogeneity of crustal protoliths. The high positive ε Nd(t) (+5.7) of the granitic vein indicates derivation from juvenile Neoproterozoic (Nd-T DM2 at 854 Ma) crustal protolith. T DM2(Nd) and T DM2(Hf) ages of 1188–2120 Ma and 2173–2480 Ma also suggest the involvement of Mesoproterozoic to Paleoproterozoic crustal protoliths. Samples show metaluminous to weakly peraluminous, high-K calc-alkaline to shoshonitic and I-type granitoid features and are similar with crustal rocks in regard to LILE (Rb, K) and LREE enrichments and HFSE (Nb, Ta, Ti) depletions. These combined features indicate slab subduction related setting for the magma generation. Slab subduction may have generated the heat necessary to provoke partial melting at the lower crustal level. Considering their position close to the Tchollire-Banyo Fault corridor, at the transition between the Adamawa-Yade and northern domains, the subduction derived features shown by the Goa-Mandja I-type granitoids could be related to the subduction of an old plate boundary during amalgamation of Gondwana. Therefore, the Goa-Mandja area records dominant magmatic accretion along the northern margin of the Congo craton (active margin) associated with a possible northwestern subduction. • The Goa-Mandja granitoids formed at 603–598 Ma. • Variable types of granitoids are identified in the Goa-Mandja area. • They were originated from heterogeneous crustal protoliths. • They are related to the subduction of an old plate boundary during Gondwana assembly. [ABSTRACT FROM AUTHOR]