تحليل ساختاري پهنه برشي سيمين - دره مرادبيك، جنوب همدان

Structural Analysis of Simin-Darreh Moradbeik Shear Zone,South of Hamedan

The Simin- Darreh Moradbeik shear zone is located in the south of Hamedan city with 5 km width and at least 10 km length. The portion of contact metamorphic rocks, plutonic rocks and migmatits are affected by this shear zone. At least three ductile deformation stages are recognized by folding and foliation of each stages of deformation. All of deformation stages are coaxial and created interference pattern of folding. Field evidence shows tension and shear stress in this area. The shear zone dips to northeast and northwest with normal sense of shear movement. This shear zone deformed locusom of migmatite, boudinage of andalusite porphyroblast and formed granitic mylonite from Khako granite. Distribution of mylonitic foliation poles show refold ing of this shear zone at the next deformation stages. According to deformation stages in Hamadan tectonites, possibly this shear zone formed syn to post second deformation (D2) Keywords: Shear zone, Migmatit, Ductile deformation, Hamedan For Persian Version see pages 39 to 46 * Corresponding author: L. Izadi kian; E-mail: Izadikian@yahoo.com