Comparative geochemical investigation of CAMP-related dolerites from Kéniéba and Taoudeni (western and northern Mali): Melting conditions and mantle source characteristics

This study presents an integrated geochemical analysis of Mesozoic dolerites from two key areas in Mali–Kéniéba and the Taoudeni Basin–within the framework of the Central Atlantic Magmatic Province (CAMP). By applying a single set of trace-element ratios to the published Kéniéba and Taoudeni datasets, it constrains their mantle sources and melting conditions within the West African Craton. The dolerites from both areas are subalkaline tholeiites derived from an enriched, within-plate mantle source with negligible crustal contamination. The Kéniéba suite is more primitive, with La/Nb ≥ 1.47, low TiO₂ (0.76–1.30 wt.%) and a narrow (Gd/Yb) N range (1.48–1.62); the Taoudeni suite is more evolved and more variable ((Gd/Yb) N = 1.37–1.98), its compositional range enclosing that of Kéniéba. The two suites thus differ in dispersion rather than in central composition, reflecting a variable range of melting conditions–variable degrees of melting and/or a variable residual-garnet contribution. Placed within the province-wide CAMP classification, neither suite belongs to a single group: the Kéniéba suite is transitional between the Prevalent and Tiourjdal fields, whereas the Taoudeni suite spreads across both. The comparison shows that the two Malian suites share a common enriched, within-plate source that does not require a deep-plume contribution, and constrains how coeval CAMP magmatism varies across the West African Craton.