Structural analysis and effect of fault system in Asmari- Jahrom Reservoir of Golkhari Field

Golkhari anticline is located in the Dezful Embayment Subzone and the hydrocarbon reservoir is the Asmari-Jahrum Formation. The presence of two subsurface thrust faults with opposite dip direction the limbs of anticline, leads to the formation of a Pop-up Structure. Based on the existence of Dashtak Formation as median detachment surface in region, the box fold shape of the anticline in structural cross sections and analysis of the geometric parameters of the sections and their comparison with the models proposed for fault-related folds indicate detachment fold geometry is considered for folding style of the anticline. Respectively, the amount of shortening in the forelimb and backlimb is 1605 m and 2160 m.The inscribed circle analysis has been applied to detect fractures in the Asmari reservoir. Using this method, the trace of axial plane of the fold can be obtained under Gachsaran Formation. By comparison with the trace of axial plane in the surface of Earth, the displacement of axial plane was calculated. The inscribed circle analysis has been applied to detect extensional fractures in the Asmari reservoir. Using geomagnetic map, satellite images and comparing their dominant fault trends with basement faults in region, their kinematic relationship were analyzed. Based on this analysis, the main shear-transverse fault zones that are located at the west (L1) and east (L2) of the anticline, their trend are similar to the basement faults. This trend is considered as main deformation zone, according to Ridel model.