The Central African Belt in the Nkambe area, northwestern Cameroon represents a collisional zone between the Saharan metacraton and the Congo craton during the Pan-African orogeny, and exposes a variety of granitoids including foliated and massive biotite monzogranites in syn- and post-kinematic settings. Foliated and massive biotite monzogranites have almost identical high-K calc-alkaline compositions, with 73-67 wt.% SiO(2), 17-13 wt.% Al(2)O(3), 2.1-0.9 wt.% CaO, 4.4-2.7 wt.% Na(2)O and 6.3-4.4 wt.% K(2)O. High concentrations of Rb (264-96 ppm), Sr (976-117 ppm), Ba (3680-490 ppm) and Zr (494-99 ppm), with low concentrations of Y (mostly<20 ppm with a range 54-6) and Nb (up to 24 ppm) suggest that the monzogranites intruded in collisional and post-collisional settings. The Sr/-Y ratio ranges from 25 to 89. K, Rb and Ba resided in a single major phase such as K-feldspar in the source. Garnet was present in the source and remained as restite at the site of magma generation. This high K(2)O and Sr/Y granitic magma was generated by partial melting of a granitic protolith under high-pressure and H(2)O undersaturated conditions where garnet coexists with K-feldspar, albitic plagioclase. CHIME (chemical Th-U-total Pb isochron method) dating of zircon yields ages of 569 +/- 12-558 +/- 24 Ma for the foliated biotite monzogranite and 533 +/- 12-524 +/- 28 Ma for the massive biotite monzogranite indicating that the collision forming the Central African Belt continued in to Ediacaran (ca 560 Ma). (C) 2008 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.