The Archean-Paleoproterozoic zone of the southern West African Craton, structured by the Sassandra shear zone, is critical for understanding the tectonometamorphic evolution during craton assembly. The Lolosso shear zone, a splay of the Sassandra shear system hosting the Kona gold deposit in western Côte d’Ivoire, provides key constraints on the interplay between deformation, metamorphism, and metallogeny across this boundary. Block-W-to-the-S, sinistral-slip shearing along the Lolosso shear zone developed under conditions of ∼610 °C and ∼4.4 kbar. In situ Rb-Sr dating of muscovite and biotite from a S-C-C’ structure yields dates of 1913 ± 11 Ma and 1871 ± 22 Ma from S- and C-related microfabrics, respectively. These results indicate post-orogenic reactivation of the Sassandra shear system through protracted deformation initiated by ca. 1910 Ma and waning deformation accompanied by localised fluid circulation until ca. 1870 Ma. Integration with regional geochronological data reveals a complex, long-lived post-orogenic history marked by multiple craton-scale deformation increments persisting up to 200 Myr post-Eburnean peak collision, ∼100 Myr later than previously considered. Nevertheless, related tectonic drivers and orogen-scale tectonic correlations are poorly constrained and therefore requires cautious interpretation. Gold mineralisation at Kona is interpreted as coeval with deformation along the Lolosso shear zone. Based on the Rb-Sr age constraint on the timing of deformation, Kona likely represents the youngest known gold deposit in the southern West African Craton, extending its metallogenic record by more than 100 Myr, pending confirmation through direct ore-mineral dating. Nevertheless, the present study highlights the exploration potential of reactivated shear zones during the post-orogenic evolution of the craton. • Integrated P-T-t-d study in the Archean-Paleoproterozoic transition of the sWAC • In situ Rb-Sr dating on micas along S- and C-microfabrics • Post-orogenic, protracted deformation between ca. 1910 Ma and 1870 Ma (∼4.4 kbar-610 °C) • Shear-zone reactivation and fluid flow persisted ∼200 Myr after Eburnean collision • The syn-tectonic Kona deposit may represent the youngest gold event of the sWAC
PERRET et al. (Sun,) studied this question.