## 3 Results
### Albert Rift Regional Tectonostratigraphy
#### 3.1.3. Tectonostriography of the Southern Lake Albert Basin
This package is subdivided into the Nyaburogo and Nyakabingo lithost stratigraphic units, which document alternating deltaic, lacustrine, and prodelta depositions. The lower section of this package is represented by the Nyaburogo unit, which is characterized by a silicified basal layer, followed by thick sequences of claystones interbedded with rust-brown to yellowish-brown siltstones and posolitic ironstones. Overlying this unit is the unit which marks the transition from low-energy shallow lacustrine to higher-energy fluvial environments, with carbonate nodules and ironstones marking fluctuating water levels and episodic sedimentation. \begin{table}
\begin{tabular}{l l l l} \hline
**Lithologic Unit** & **Age** & **Characteristics** & **Tectonic and Depositional Interpretation** \\ \hline \multirow{4}{*}{Oluka Formation} & \multirow{4}{*}{Late Miocene to Early Pliocene} & Dark shale at the base, overlain by & \multirow{4}{*}{Represents deltaic, mudflat, and lacustrine settings influenced by episodic tectonics and climatic changes. Sharp gamma-ray increases in logs indicate significant shifts in depositional energy.} \\  & & & Silicified basal layer, thick claystones interbedded with rust-brown to yellowish-brown siltstones and posolitic ironstones. & Reflects deposition in delta plain, prodela, and shoreline settings, shaped by fluctuating depositional energy. The silicified beds mark renewed rifting, while overlying claystones indicate low-energy lacustrine conditions. & \multirow{4}{*}{Represents floodplain, liposomal, and lacustrine deposition under humid conditions. The basal shales reflect a deep lake setting, transitioning to higher-energy fluvial and floodplain deposition due to increased sediment supply.} \\  & & & & Carbonate nodules suggest fluctuating water levels. \\  & & & & Carbinates the transition driven by uplift of the Newzeror Massif, altering lake dynamics and sediment provenance. Reflects lacustrine and shoreline environments influenced by fluctuating lake levels, tectonic uplift, and climate variability. \\ \hline \end{tabular}
\end{table} 
Table 3: \(Cont.\)Early Pleistocene to Present Rifting Phase  
The period from the Early Pleistocene to the present marks a transitional phase in the basin's evolution, driven by the uplift of the Rwenzori Massif, which split the regional lacustrine basin into two distinct basins, altered sediment provenance, and triggered molluscan changes; this period is captured in the Nyabusozi Formation, characterized by a basal massive sandstone layer with low gamma-ray response overlain by alternating sands and clays interbedded with ironstone layers, reflecting dynamic depositional processes in lacustrine and shoreline environments influenced by fluctuating lake levels, tectonic uplift, and climatic variability. Overall, the southern Lake Albert Basin represents the most complete sedimentary fill and records all the known tectonic and climatic shifts since the early Miocene (Figure 6). Figure 6: Generalized geological and climatic events chart for the Southern Lake Albert Sub-basin (Semliki) that represents the most complete stratigraphy of the rift sediments. The climate curve is based on [PERSON] [37] and [PERSON] et al. [38].