SSRG International Journal of Geo-informatics and Geological Science Volume 8 Issue 2, 37-44, May-Aug, 2021 ISSN: 2393 – 9206 /doi: 10.14445/23939206/IJGGS-V8I2P104 © 2021 Seventh Sense Research Group® This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) Geology and Geochemical Studies of Metatexite And Diatexite Migmatites From Bauchi, Northeastern Nigeria Muhammad Nafisatu Magaji* 1 , Ahmad Isah Haruna 1 , Abdulmajid Isa Jibrin 1 , Oshelike Ishioma Bridget 1 1 Department of Applied Geology, AbubakarTafawaBalewa University, Bauchi, Nigeria. Received Date: 30 May 2021 Revised Date: 02 July 2021 Accepted Date: 11 July 2021 Abstract - The study addressed the geochemical properties of rocks of the study area. In this study, the geological mapping was done on a scale of 1:25,000 through an orderly method of mapping along with profiles from one outcrop to another by noting road and river channel that reveals subsurface lithology to understand the geology of the area. Samples of fresh representative rocks units were taken at each location with a corresponding coordinate. A total of 20 samples were collected, sorted, and grouped using Sawyer’s (2008) first- and second-order morphological classifications of migmatites into four on the basis of morphology, and ten (10) representative rock samples were picked for whole-rock geochemical analysis (XRF). The results obtained show that the area has four distinct lithologic units. Viz, metatexite, melanocratic diatexite, mesocratic diatexite and leucocratic diatexite of different morphologic classes. The range of silica for metatexites and diatexites are 54.3wt.% to 65wt.% and 79.7wt.% to 86.0wt.% respectively. Both the metatexites and the diatexites shows overlapping compositions and the decreasing/ increasing trends on harker diagrams indicates that both are petrogenetically related. However, from the plot of frost tectonic discrimination the rock groups occupy both the ferroan and magnesian fields and relating it further to alumina saturation index, the peraluminous property of the diatexites implies high development of k-feldspar with continuous fractional crystallization, as the system is cooling and temperature is dropping in forming the leucocratic diatexitest I. INTRODUCTION The study area falls within Bauchi sheet 149 N.E within the northeastern Nigerian Basement Complex with coordinates of latitudes N10 0 21’00” & N10 0 23’00” and longitudes 09 0 50’00” E & 09 0 55’00”E (figure.1). The area of study is characterized generally by low to medium level outcrops and covers a total landmass of about 42 square kilometerswith an average elevation of 590 meters above sea level. The area is fairly accessible through untarred roads, footpaths and cattle tracks with a network of stream channels. This present work is aimed at understanding the geology and geochemical properties of rocks within the study area with emphasis on the morphological forms. Figure 1: Location map of the study area drawn from Arcmap 10.1 II. Literature Review The study area falls within the Neoproterozoic Trans- Saharan Belt and the Migmatisation has been dated to 500±100Ma (Ferre, 2006). It was suggested to be formed from the converging West African Craton, the Congo Craton and East Saharan Block which was probably a Craton until 700Ma (Black and Liegeois, 1993) when it was widely and largely reactivated, except in few areas. It rocks are mainly metamorphic consisting of monotonous granite-high-grade gneisses and migmatites cut by large Pan-African monzogranite plutons. Also, the close relationships between the regional tectono-metamorphic evolution of gneisses, regional anatexis and emplacement of syn-kinematic plutons from the monzodioritecharnockite association within the study area strongly suggest that the area underwent a monocyclic metamorphic history (Ferre et al, 1998). Moreover, migmatites are high-grade rocks that have been formed by partial melting, developed in various tectonic settings and can affect a wide range of protoliths. Consequently, rock packages are commonly chemically inhomogeneous at a variety of scale, so also the process of migmatisation is correspondingly inhomogeneous throughout