New interpretation of some structures in cover rock basedOn basementStrike-slip faults in Darab area.
|Category||Tectonic & Seismotectonic|
|Location||21th symposium on geosciences|
|Holding Date||24 May 2008|
Many if not most secondary structures and complex structural patterns in orogenic belts are produced due to wrench faults movements. The study of such complex structural patterns can be used for distinction of concealed wrench faults.
In Darab area, 250km southeast Shiraz that belongs to high Zagros tectonic province, a complex structural pattern exists. According to the new hypothesis about the deformation of cover rocks above a ductile shear zone in the basement. Existed structure in the area can be interpreted as secondary features which commonly form in cover rocks above a major strike-slip fault in the basement. This mentioned fault is continuation of a huge strike-slip fault in north of Neyriz area that causes a big curvature in main Zagros thrust fault.
Mesoscopic and Microscopic studies in Neyriz area revealed the rotation of some outcrops in response to movement of mentioned fault.
A structural pattern can be built up with respect to some features such as: exhumation of older formations in locally uplifted areas and in an en-echelon form, existence of many Riedel shears and finally locally extended normal faults. The relation between these structural patterns and strike-slip fault in basement is obvious. In addition there are many thrust and .reverse faults that have formed due to bends and step over in strike-slip faults