ICP-MS U-Pb zircon ages from the Nyong Complex of southwestern Cameroona part of the West Central African Fold Belt-trace Late Mesoarchean (2,850 Ma), Middle Palaeoproterozoic (2,080 Ma), and Neoproterozoic (605 Ma) events: Two meta-syenites and the protolith of an amphibolite are Late Mesoarchean; two meta-granodiorites are Middle Palaeoproterozoic; the amphibolite may have recrystallized in the Middle Palaeoproterozoic; all rocks are overprinted by the Neoproterozoic event. Integration with published data shows that our amphibolite sample has one of the oldest amphiboliteprotolith ages (2,810 Ma) reported so far. It shares the Middle Palaeoproterozoic metamorphism/recrystallization with other, previously dated amphibolites. An earlier reported metamorphic zircon age (2,090 Ma) from eclogite is somewhat older than the regional Middle Palaeoproterozoic metamorphism/recrystallization ages (2,040 Ma) reported from amphibolites. Thus, the eclogite-amphibolite ages may date an exhumation process. A published charnockite age, interpreted as an Early Mesoarchean crystallization age, is older than the Late Mesoarchean meta-syenite and amphibolite-protolith dates; its Middle Palaeoproterozoic metamorphism/recrystallization age, however, is identical with the metagranodiorites and amphibolites. The Neoproterozoic ages demonstrate the regional overprint of the Nyong Complex during this period. Integration of the Nyong Complex ages with published ones from the entire West Central African Fold Belt, and comparison with those from West Africa and South America, support their common origin from the Palaeoproterozoic collision between the Archean Congo and São Francisco shields.

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