The study of structural geometry and detachment levels of the East Darreh-Baneh anticline, Lurestan zone, west Zagros

The East Darreh-Baneh anticline is located in the Lurestan structural zone, west of the Zagros fold and thrust belt. In this zone thrust faults and detachment horizons have a main role in geometry and kinematic of the folded structures. In this research, deformational pattern and structural geometry of the East Darreh-Baneh anticline have been studied using interpretation of five 2D seismic profiles, drawing of structural cross sections, drilling well data in the adjacent anticline and related analysis. Accordingly, the East Darreh-Baneh anticline is a detachment folding, in which two upper and middle detachment levels is affected its structural geometry. In the study area, the shaly Garu and the flysch Amiran formations caused deformations as a middle and upper detachment levels, respectively. The high thickness of the upper detachment level caused formation of the anticlines in surface with low wavelength and amplitude and formation of the surface disharmonic folding on deep-seated anticlines. Also, geometrical parameters analysis of the East Darreh-Baneh anticline indicate that this anticline is an asymmetric and noncylindrical fold and from tightness view is open to gentle with wide aspect ratio