نوع مقاله : مقاله پژوهشی
نویسنده
گروه زمینشناسی، مدیریت اکتشاف، شرکت ملی نفت ایران، تهران، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
The Bangestan Anticline, located in the transition zone between the Dezful Embayment and the Izeh Zone, is one of the most complex tectonic structures in the Zagros Basin, and is of high exploration significance due to the absence of Asmari Formation outcrops in the subsided portions. This research was conducted with the aim of analyzing the structural evolution and folding geometry of the Bangestan Anticline, utilizing extensive field surveys, analysis of shear and tensile joint systems, and construction of structural cross-sections using the kink method. To enhance modeling accuracy, surface data were integrated with information from 8 exploratory and development wells (such as the deep wells Bangestan-1 and Khaviz-1) in the ArcGIS and AutoCAD Map software environments. The findings indicate that this anticline is a "faulted detachment fold" with an asymmetric and box-like geometry, whose evolution is directly controlled by the Mountain Front Fault (MFF) and intermediate detachment horizons, particularly the Dashtak and Kazhdumi formations. Cross-section modeling demonstrates the existence of systematic axial displacement between the surface horizons of the Asmari and the deep reservoirs of the Bangestan Group, such that with increasing shortening from northwest to southeast, the axial plane has migrated toward the southwest (foreland). Additionally, the conjugate joint array on the steep limbs plays a key role in enhancing the secondary permeability of the carbonate reservoirs. The final results, confirming the tectonic inversion model and identifying specific folded structures, showed that surface geometry is not necessarily predictive of the reservoir crest position at depth. This phenomenon, confirmed by stratigraphic repetition in recent drilling, elucidates the necessity of revising the determination of drilling locations based on structural displacements at depth.
کلیدواژهها [English]
)