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The 2.1 Ga Kedougou-Kenieba Inlier in West Africa hosts outstanding mineral wealth, with ~45 Moz of gold and 630 Mt of iron ore hosted along the Senegal-Mali Shear Zone (SMSZ). To the west of the SMSZ the Faléme’ Volcanic Belt (FVB). Detailed petrography and analysis of igneous rocks by solution lCP-MS and AES show that the FVB is comprised of calc-alkaline volcaniclastic sediments, lavas and plutonic rocks, hosts iron ore in a series of magnetite skam deposits. To the east of the SMSZ, the Kofi series is comprised of clastic sedimentary rocks and peraluminous granite plutons. Orogenic Au hosted in the Loulo-Bambadj i district of the Kofi Series (including the Gara, Yalea and Gounkoto mines) is spatially associated with epigenetic tourmaline alteration, while widespread albite alteration is associated with early stages of mineralisation in both the FVB and the Kofi Series. A >400 ppm boron soil anomaly along >100 km strike length of the SMSZ is related to widespread tourrnalinisation of sedimentary rocks in the Kofi Series. The Au deposits of the Kofi Series are characterised by a Fe-As-Cu-Au-Ag i REES-W-Ni-Te metal association. Ore assemblages are pyrite and arsenian pyrite dominated with accessory chalcopyrite, Ni-sulphides, scheelite and REE phosphates. Two distinct hydrothermal fluids were involved in Au mineralisation in the Kofi Series: 1) a moderate temperature (315-340 °C), low salinity |
