Geological field mapping project of the Semliki basin of the Albertine graben area in Ntoroko district in Western Uganda.

Abstract

The field trip was carried out from the 3rd to the 10th of January 2022. The area of study was the Semliki basin located in the southern part of the Albertine graben, Ntoroko district in western Uganda. Semliki area lies onshore south of Lake Albert, it is bounded by the escarpment to the east and south and by rivers Lamia and Semliki to the west. It covers approximately 1200km². The Semliki Basin is one of Uganda's most promising hydrocarbon exploration basins. It is located within one of Uganda's authorized exploration zones. It is the northernmost portion of the vast East African Rift System (EARS) and is located within its western arm. The goal of this research is to enable students pursuing a Bachelor of Science in petroleum Geoscience and Production to apply geological, geophysical, and other forms of knowledge to better understand the geology and petroleum system of the area, as well as to investigate the depositional environments and processes that have occurred in the area. During the field mapping exercise, structural and stratigraphical data were collected, processed, and conclusions about the Semliki basin's petroleum potential were drawn. Fluvial sediments, deltaic sediments, and lacustrine sediments are among the sediments found in the research region. The Semliki Basin is a tectonically active basin subjected to various tectonic events, resulting in the production of primary and secondary structures in both the basement and sediment rocks. Bedding, cross-stratification, and troughs are primary structures, while joints, faults, and mud cracks are secondary structures. To gain a complete understanding of the rocks and sediments that fill the Semliki basin, sedimentology, stratigraphy, and tectonics are used. This data was utilized to determine the geologic history of the rocks and assess their economic value. We concluded that the research region had a good petroleum system, which included source rocks (organic-rich shales), reservoir rocks (thick sandstones), seals (thick clay layers, thick layers of fine-grained sands), traps (faults, diapirs), and migration pathways (cross-beds, faults, and beds).

The area of study was the semliki basin Located in the southern part of the Albertine graben, Ntoroko district in western Uganda