Basin analysis and hydrocarbon maturation, Unity and Kaikang area, Muglad Basin, Sudan
Basin analysis study has been conducted along a cross section in the Unity-Kaikang area, Muglad Basin, Sudan. The research is based essentially on geological, seismic investigations and basin model approach. The basin model approach included two dimensional gravity modelling, and one dimensional thermal history, maturation and hydrocarbon generation modelling. In addition an investigation of the hydrocarbon migration processes, routes to the known and probable accumulation targets is studied. The basin models were calibrated against data obtained from wells drilled in the area. The seismic investigations indicate a sedimentary thickness ranging from 11 to 7 km averaging 9 km along the area of the cross section. The two dimensional gravity model suggests a mantle uplift of 2.18 km and a β stretching factor of 1.47 with a thin crust of 24 km, corresponding to an extension of 45 km. The burial and thermal model suggests a high subsidence rate accompanied by a slow sedimentation rate during the Neocomian and Aptian times. The present heat flow is ranging between 72 (Kaikang area) to 50 mW/m2 averaging 59 mW/m2 along the cross section of the study area. The paleoheat flow is averaging 57 mW/m2 with peaks of 65 mW/m2 during the Aptian-Senomanian, Paleocene to Eocene times and a last peak of 59 mW/m2 between the Miocene and the present. The maturation and hydrocarbon generation model (LLNL, Sweeny 1990) has been applied to the oil prone source rocks of the Abu Gabra and Sharaf formations. For the purpose of modelling the Abu Gabra Formation has been divided into three layers. In the top layers of the Abu Gabra Formation, the model predicts an average onset of oil generation at 90 Ma and an end at 10 Ma. In the combined source rock section of layer three of the Abu Gabra and the Sharaf Formation the model predicts an average onset of oil generation at 110 and an end at 30 Ma.