The field and microstructural study of Malayer plutonic rocks,west of Iran

Abstract

A detail field and microscopic characteristics of Malayer Plutonic Rocks (162-187Ma), west of Iran, are discussed in details to evaluate relationships between deformation and pluton emplacement. The studied rocks were injected into the slate, phyllite and schists of so called "Hamadan phyllites and slates" in the Sanandaj-Sirjan zone. Studies have shown that there is a continuity from magmatic to solid-state deformation and latter deformation overprint the magmatic structures. The brittle deformation such as deformed granite sheets, (sub)mylonites and migmatites occurred in the region is subjected to tectonic forces after cooling the pluton and imply the persistency of regional deformation. The continuity from liquid to solid state deformation suggests a syntectonic emplacement of pluton. These features display a shearing deformation in the pluton. Porphyroclasts in the sheared rocks show dextral shear sense. Overall microtectonic features show that the pluton was emplaced synchronously with respect to the regional scale deformation in the high-strain environment.