Effect of detachment levels, thrust and basement strike-slip faults on structural geometry of the Naft anticline in the Lurestan zone, West Iran

The Naft anticline with NW-SE trend is located in north of the Lurestan sub-zone and the Zagros fold and thrust belt. Thrust and basement strike-slip faults and detachment levels play an important role in the structural geometry of the folded structures in this is sub-zone.  In this research, deformational pattern and structural geometry of the Naft anticline hane been studied using constration a cross-section perpendicular to the anticline axis in the central part and relenat analysis. Two upper (Amiran Formation) and Middle (Garau Formation) detachment levels and deelpy thrust fault in the southwestern limb have the main affect on folding geometry and led to the formation of disharmonic folding. An N-S basement strike-slip fault in the middle part of the anticline has shifted the anticline axis from N70W in the northwest to N50W in the southeast. In addition, the shallow thrust fault and detachment levels caused the formation of an axis of two kink and curved hinges in the middle part of the Naft anticline. Measurement of geometrical parametrical of the Naft anticline indicate that this anticline is an asymmetrical, noncylindrical fold and from tightness view is open is half-angle round.