## 4 Discussion
### Thermal Maturity, Hydrocarbon Generation and Expulsion  
Measured Ro values in Well TRC increase from 0.24% at 620 m to 0.47% at 2330 m, indicating that most of the well section is too thermally immature for hydrocarbon generation. The top of the main oil generation window (Ro 0.5%) occurs at approximately 2500 m. Present-day geothermal gradient data suggest a higher maturity level than the measured values, possibly due to recent increases in heat flow and geothermal gradient near geothermal springs and shallow magma chambers [55; 56; 57; 58]. The current hydrocarbon transformation ratio (HTR) of 0.2-0.3% for well TRC reflects a low level of hydrocarbon generation, with ongoing maturation. Pseudo-well X suggests that the source rock is in a peak oil window stage. The increase in Vr, from 0.66% Ro at the top to 0.84% Ro at the base, indicates deeper burial and higher thermal maturity. The current HTR of 60% reflects an advanced hydrocarbon generation, with rapid increases in recent thermal burial. The Kasande shale, with advanced maturation and high HTR in the deeper sections, is a mature source rock with substantial hydrocarbon-generation potential. The progression of Vr and HTR over time indicates the presence of an effective hydrocarbon generation, which is likely to continue as it remains in the late stages of the oil window and approaches gas generation. This high HTR (60%) suggests a significant hydrocarbon expulsion, indicating the potential for migration into nearby reservoir rocks. Future exploration should focus on identifying and assessing potential reservoirs and migration pathways to predict potential hydrocarbon entrapment. Modeling results show that the Albert Rift is a young petroleum system, with hydrocarbon generation and expulsion starting in the Early-Mid-Pliocene in the depocenters. Some traps are still receiving hydrocarbons at present, suggesting potential for new accumulations in the rift. A clear understanding of the timing of petroleum generation and expulsion in relation to neo-tectonic evolution is crucial for identifying and assessing future hydrocarbon prospects. Seismic data from the Semliki and Lake Edward Basins indicate that the Albert Rift is highly faulted and likely compartmentalized, with a high concentration of both normal and reverse faults (e.g., Figure 8). Given the interbedded nature of shales and sandstones in the sedimentary section, shale smearing along faults may contribute to fault-sealing. Future studies should focus on determining the sealing or leaking capacities of these faults. In the Albert Rift, some fault systems act as conduits for fluid flow, whereas others act as barriers to fluid migration through mechanisms such as clay gouge development and fault zone alteration, which create low-permeability zones that effectively seal reservoirs [1]. Vertical hydrocarbon migration is particularly restricted where fine-grained formations, such as the Kasande and Oluka, are juxtaposed against the more permeable Kisegi and Kakara reservoir units. However, fault reactivation due to ongoing tectonic activity could compromise reservoir integrity by reopening previously sealed faults and creating new migration pathways, potentially leading to hydrocarbon leakage or redistribution outside of traps. This phenomenon is particularly evident in the Kasindi-Bantu Fault Zone in the Lake Edward Basin, where fault reactivation may influence both fluid migration and hydrocarbon accumulation in apron fans and deltaic systems, as evidenced by a string of oil seeps. Oil seeps along faults are a common feature in the Albert Rift, underscoring the potential negative impact of faulting on reservoir integrity. Previous studies (e.g., [2; 15; 22; 24; 25]) suggest that before the Pliocene-Pleistocene boundary, the Albert Rift functioned as a single fluvial-lacustrine system hosting a unified regional petroleum system. The uplift of the Rwenzori Massif subsequently compartmentalized the rift into two main basins, north and south of the massif.