STRUCTURAL MODELING AND PETROPHYSICAL EVALUATION FOR RESERVOIR CHARACTERIZATION OF SEMLIKI BASIN, WESTERN UGANDA.BRIGHT OSUAGWU AND ANDREW KATUMWEHE

An integrated interpretation of seismic and petrophysical data was employed to build structural model and characterize the hydrocarbon potentials of the Semliki Basin, western Uganda.

Three dimensional (3D) seismic data and a suite of well logs from three (3) wells acquired over the Semliki Basin were interpreted. The wells were correlated across the field to delineate the lithology and establish the continuity of the reservoir sands and the general stratigraphy of the study area. Two hydrocarbon bearing sands were evaluated. 3D seismic data was used to identify the fault and map the horizons and generate the time and depth structural maps. The trapping mechanism was portrayed to be mainly fault-assisted anticlinal closures and some stratigraphic trapping components while the overall geometry of reflectors is parallel to sub-parallel.

Fault polygons and grid data were used as a structural framework and shows that the growth fault and roll over anticlines primarily controlled the sequence architecture in the study area. The structural model provides basic framework necessary for the characterization of the reservoir through a static model. The petrophysical analysis shows that the mapped reservoirs suggest good quality, multi-stacked and indicates hydrocarbon accumulation. These results suggest more development opportunities in the Semliki Basin and demonstrated the efficacy of structural modeling and petrophysical evaluation for reliable reservoir characterization.

KEY WORDS: Structural modelling, Seismic data, Petrophysics, Reservoirs, Semliki Basin.