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.