Interpretation of aeromagnetic data to detect the deep-seated basement faults in fold thrust belts: NW part of the petroliferous Fars province, Zagros belt, Iran

Abstract

Detection and delineation of basement faults are fundamental exercises in petroleum geology. This is because such structures can guide later deformation and the associated structures within the younger overlying sediments. This work presents aeromagnetic data interpretation and a comparison with the Digital Elevation Model (DEM) to detect basement structures covering the NW part of the petroliferous Fars province, Zagros belt. Anticlinal axes deflect in the NW-part of the province. The reason for this deflection is debated. We identified basement faults from the airborne geomagnetic data. Tilt filtering was applied on the magnetic data to enhance such faults. Two NE-trending cross-sections perpendicular to the anticlinal axes were prepared to show the effect of the basement faults in the sequence stratigraphy. The results of this research indicate a major NW and another NE trending deep-seated fault. Most of the extracted magnetic lineaments correspond to these faults. These faults were confirmed by the high displacement of the layers and changes of the thickness in the sequence stratigraphy. The result of this research suggests that the deep-seated basement faults are the main controlling factor of structural style in the NW part of Fars province in terms of a thick-skinned tectonics.