Influence of Sub Hersinian and Sub Senonian tectonic phase in Aghajari Oil Field (Wells No. 56, 140, 82)

In order to examine the influence of Sub-Hersinian and Sub-Senonian tectonic phases in the Aghajari Oil Field, three stratigraphic sections were studied around the boundary of Sarvak and Ilam formations in wells Nos. 56, 140 and 82. The existence of biozone No. 29 (Wynd, 1965) with Turonian in age at the top of the Sarvak Formation which overlays the biozone No. 25 (Wynd, 1965) indicates the continuity of sedimentation from Cenomanian to Turonian. The effect of Sub-Hersinian phase was minor and caused some facies changes in all three wells. In wells Nos. 56 and 140, the biozone No. 29 (Wynd, 1965) with Turonian in age is overlain by the biozone No. 30 (Wynd, 1965) which belongs to the Ilam Formation. This condition represents a gap between Turonian and Santonian at the boundary of the Sarvak and Ilam Formations which is the result of the Sub-Senonian phase. In well No. 82, the time of this gap is slightly more and continued until the Late Santonian as a result of the Gurpi Formation with Late Santonian in age which has overlain the Sarvak Formation with Turonian in age.