BSE-CL images, U-Th-Pb abundance, and U-Pb ages were obtained for zircon crystals from Nkogho I-type anatectic granitic basement cropping in the Mamfe Basin (SW Cameroon).These data were used to characterize, classify each zircon crystal and elucide their registered information.They were also used to develop a formation model to their host and source rock, and present registered post-emplacement events.The studied zircons ranging in size from < 75 to >150 µm, form long and short prisms, pyramidal to dipyramidal with few subspherical, subhedral and anhedral crystals.They show oscillatory zoning, complex growth zoning, sector zoning, patchy zoning, faint broad zoning, a preserved xenocrystic core with overgrowth rim, or are unzoned.These features are mainly compatible with those of igneous zircons.The U (30-6380 ppm), Th (4-1280 ppm), and Pb (12-648 ppm) contents show core, zone and rim variations with most values being within the range limit in igneous crustal granitic zircons.The Th/U ratios (0.08-1.23) with core, zone and rim difference mainly enclose values of magmatic zircons with few values characterizing metamorphic zircon grew in equilibrium with an anatectic melt.The U-Pb age (108.4 ± 1.7 -988.4 ± 19 Ma) with some core and rim difference date: Early Neoproterozoic, Cryogenian-Ediacarian, Early Cambrian-Ordovician, Devonian-Carboniferous, and Aptian-Albian, events.The Nkogho I-type granite was formed during Cryogenian to Ediacarian times from slow cooling of a deep-seated crustal magma originated from partial fusion of a preexisting grantic protolith.This rock underwent partial fusion with granitization during Early Cambrian-Ordovician, Devonian-Carboniferous, and Aptian-Albian periods.The Aptian-Albian periods can date the opening of the Mamfe sedimentary basin (the southernmost Cameroon portion of the Benue Trough).
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