Geology, Geochemistry and Geochronology of the Gold mineralization hosting Syenite, Tulu Kapi, Western Ethiopia: A Review Temesgen Oljira 1*2 and Geleta Warkisa 1 1 Department of Geology, Faculty of Natural Sciences, Salale University, P. O. Box 245, Fiche, Ethiopia 2 Pan African University Institute of Life and Earth Science Including Health and Agriculture (PAULESI), Ibadan, Nigeria Abstract: The Neoproterozoic (900-600 Ma) Arabian Nubian Shield is an example of Precambrian plate tectonics and arc accretion. The Western Ethiopian Shield (the southern extension of ANS) is geo-tectonically a characteristic of lower grades of Metavolcano- sedimentary sequences of ANS intruded by associated felsic granitoid and mafic bodies and at the same time it is contained of gneisses rocks of the MB. The Gold mineralization and alterations initiating throughout the Tulu Kapi syenite are in the form of in enechelon vein arrays and related structures, which are controlled by conjugate shear zones in the syenite and steep N-S striking structures. The earliest recorded deformation and alterations revealed the syenite albitization which is the one hosting for gold mineralization and it has been widely overprinted by multistage hydrothermal system that appears to have been controlled mainly by veins, crackle zones, fractures and minor breccia zones. Primary gold mineralization displays spatial and temporal relationship with Tulu Kapi syenite and the Kapi gabbro, both of which host gold mineralization, are 738.3±2.6 Ma and 699.5±2.7 Ma period, respectively, in a volcanic arc subduction syn-collisional tectonic setting by the fractionation of underplated, LREE-enriched basaltic magma with substantial crustal input to possible crustal melting. The underplated basaltic magma had been sourced from LREE-enriched mantle by subduction of sediment laden crustal slabs at a subduction zone. Fractional crystallization involved formation of Ca-rich plagioclase, which continually reacted with hydrothermal fluids to more fractionated Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 25 September 2020 doi:10.20944/preprints202009.0598.v1 © 2020 by the author(s). Distributed under a Creative Commons CC BY license.