A report on the geologic mapping of area c, Igayaza, Isingiro District, Western Uganda from 31st January, 2022 to 7th February 2022

Abstract

This report comprises a detailed compilation of aims, methods, findings, interpretations, conclusions and recommendations for the Igayaza-Isingiro geological mapping exercise and field excursion to south western Uganda. The mapping project began on Monday 31st January 2022 with a one day briefing on expectations from the staff and students and the project ended on 7th February, 2022. The Geological mapping exercise was carried out in Igayaza, Isingiro district, western Uganda which lies within the Karagwe-Ankolean system of rocks (ca. 1400-950 Ma), which is the northern most extension of the Kibaran mobile belt with the aim of acquainting students with skills in geological mapping. The materials used during the mapping exercise included a geologic hammer, handheld GPS, notebook and a compass. After field work, the rock samples collected were sorted and taken to the laboratory for further analysis i.e. petrography and thin section analysis. The data acquired for structures compiled with laboratory data was interpreted and analyzed. The findings were compiled with its interpretation made. The lithology comprised of thin arenaceous formations that were predominated by quartzites while the thick argillaceous formations constituted shales. The quartzites were mainly found at the ridge summits while the shales were found along the flanks of ridges and in valleys between ridges. The grades of metarmorphism was varying from low grade regional metamorphism which was evidenced by presence of beddings and some index minerals such as chlorite, muscovite. Sandstones and shales were metamorphosed to quartzites and phyllites respectively. Contact metamorphism occurred around granitic intrusions that formed most of the arenas (broad stadium like structures). The structures in the mapped area include joints, beddings, faults, quartz veins; these were mapped at different scales. The economic potential of the area is low since no economic minerals have been discovered. However, some of the economic activities carried out include; farming, cattle keeping, quarrying and brick making. v At the end of the mapping exercise, hotspot presentation were done where students would take lecturers to the most interesting areas, oral presentations were made physically at the hotspots by all different groups.