Petrochemical constrains on the origin and tectonic setting of mafic to intermediate dykes from Tikar plain, Central Cameroon Shear Zone

Abstract The Tikar plain is located on the Cameroon Central Shear Zone. It also part of North Equatorial Pan-African Belt. formed granitoids intruded in places by mafic and intermediate dykes. dykes are essentially banded gabbros composed plagioclases, pyroxenes, amphiboles, biotites opaques. Their textures range from porphyroblastic to porphyritic. monzonites monzodiorites characterized, respectively, cataclastic mylonitic textures. minerals identified potassium feldspar, epidotes, sphenes Seritization reaction mostly present dykes, while chloritization much more pronounced high-k calc-alkaline shoshonitic. They characterized low moderate SiO 2 content (42.08–61.96 wt%), high TiO (0.47–2 wt%) Ni (1.48–99.18 ppm) contents. show fractional trends with negative anomalies Zr, U P positive Rb, Ba, Ta, Pb Sr multi-element diagrams, Nb, Ti relative Ba Pb. rare-earth elements (REE) patterns Eu for REE spectrum all shows enrichment LREE relatively flat HREE, which can indicate arc magmatism. In Zr–Ti/100–Sr/2 diagram, plot island tholeiite basalt fields. Th, Nb concentrations that subducted lithosphere crustal component contributed generation plain. geochemical characteristics suggest their derivation a various degree partial melting garnet spinel facies, probably between depths 80 100 km. collision African Fold Belt northern edge Congo craton resulting thickening, sub-crustal lithospheric delamination upwelling asthenosphere may have been principal process magma dyke would migrated through faults network Zone before crystallizing granito-gneissic basement rocks.