Earth Sciences Malaysia (ESMY) 6(2) (2022) 82-92 Quick Response Code Access this article online Website: www.earthsciencesmalaysia.com DOI: 10.26480/esmy.02.2022.82.92 Cite The Article: Michael T. Asubiojo, Kazeem O. Olomo, Johnson Ajidahun, Toheeb O. Oyebamiji (2022). Controlled Method of Determine Gold Mineralization Potentials in an Unexploited Area; A Case Study of Itagunmodi and Osu, Southwestern, Nigeria. Earth Sciences Malaysia, 6(2): 82-92. ISSN: 2521-5035 (Print) ISSN: 2521-5043 (Online) CODEN: ESMACU RESEARCH ARTICLE Earth Sciences Malaysia (ESMY) DOI: http://doi.org/10.26480/esmy.02.2022.82.92 CONTROLLED METHOD OF DETERMINE GOLD MINERALIZATION POTENTIALS IN AN UNEXPLOITED AREA; A CASE STUDY OF ITAGUNMODI AND OSU, SOUTHWESTERN, NIGERIA Michael T. Asubiojo * , Kazeem O. Olomo, Johnson Ajidahun, Toheeb O. Oyebamiji Department of Earth Sciences, Adekunle Ajasin University, Akungba Akoko, Nigeria * Corresponding Author E-mail: michael.asubiojo@aaua.edu.ng This is an open access journal distributed under the Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited ARTICLE DETAILS ABSTRACT Article History: Received 02 February 2022 Accepted 04 March 2022 Available online 08 March 2022 The research was conducted to open up further unexploited areas for gold mineral exploitation in part of Ilesha schist belt using geological and geophysical approach. Itagunmodi was used as a control in order to determine the mineralization potentials of Osu as a case study. Both towns lie within Ilesha schist Belt, Southwestern Nigeria. The residual magnetic anomaly map of the study area revealed magnetic low in the two towns indicating the presence of geological structure serving as a conduit for mineralizing fluid. Airborne radiometry interpretation showed that both Itagunmodi and Osu are affected by hydrothermal alteration which is an indication of gold mineralization. Overall interpretation of aeromagnetic and airborne radiometry datasets show that hydrothermal alteration generally is associated with fault and shear zones in the study area. The isolated altered zones were subjected to further investigation by using six samples of stream sediment collected along Imo (Itagunmodi) and Olomumu (Osu) stream channels for the grain size and geochemical analyses. The results from the grain size analysis revealed that sediments in both areas are fine to medium grained, poorly sorted, fine to moderately fine skewed, which implied fluvial depositional settings, and revealed that the occurrences of gold mineralization in both areas are of secondary deposits (alluvial). The concentration of identified trace elements as related to their threshold values revealed similar contents of low to high concentrations in both areas. The results of the analyses observed in Itagunmodi are similar to that of Osu, which implies that Osu is also mineralized will gold deposit. KEYWORDS gold-mineralization, grain size, pathfinder elements, magnetic anomaly, Itagunmodi, Osu 1. INTRODUCTION The rise in demand for gold and its global price increase has sparked interest in both the local and commercial mining of this noble metal. Most of the already discovered areas of these deposits are being exploited daily without any hope of being replenished due to its non-renewable nature. The Itagunmodi area has shown to be an excellent location for gold mining with visible presence of artisanal miners engaging in panning, while the Osu area which is short distance to Itagunmodi is yet to be explored. Hence, the need to open up gold mineralization potentials in Osu, by using Itagunmodi mineralised as control formed the basis of this study. Gold is a solid naturally occurring noble metal of economic interest. It has unrivaled history by any other metal due its perceived value and enormous use that include jewelry, dentistry, electronics, coin and investment among others. The occurrence of gold is found in trace amounts in almost all basement rocks. It is abundant in Earth's crust, and is estimated to be approximately 0.005 parts per million (Encyclopedia Britannica, 2020). Except for tellurium, selenium, and bismuth, gold mostly occurs in its native state, and remains chemically uncombined. Gold is commonly found in association with other metallic deposits like copper, lead and other constituent elements. The possibility of finding large masses of gold- bearing rock rich enough to be called ores is commonly unusual. Gold production in Nigeria is thought to have begun in 1913 and peaked between 1933 and 1943 (Nigeria Ministry of Solid Minerals Development, 2008). The occurrence of gold mineralization (GM) in the study areas is divided into two which are primary deposit in form of quartz vein, fracture, and fault, and secondary deposits which are alluvial and eluvial (both consolidated and unconsolidated that are formed by surface weathering and erosion of primary gold-bearing rocks) (Oyinloye, 2011). It has been reported that only 5-10% of Nigeria gold productions come from vein deposits, while the majority comes from modern alluvial derived from basement rocks (Encyclopedia Britannica, 2020). A group of researchers defined four gold fields encompassing the main producing areas in Nigeria, they are: Ilesha-Egbe, Minna Birnin-Gwari, Sokoto, and Yelwa (Woakes and Bafor, 1984). All are associated with schist belts, though gold-quartz veins can also be found in gneisses (e.g. Malele, Diko and Iperindo). The study areas fall within the Ilesha-Egbe Schist Belt in southwestern Nigeria. The rocks in Ilesha schist is of Precambrian age which are characterize by gold mineralization (GM). Artisanal miners engaging in panning focus more on alluvial deposits across the study areas. Previous researchers in the study areas have focused more on Itagunmodi