Petrology and geochemistry of the plutonic complexes of the Marivan area, Sanandaj-Sirjan zone

The plutonic complexes of Marivan area, composed of two types of plutonic rocks of different genesis, are situated in the northwest of Sanandaj-Sirjan metamorphic belt. The stratigraphical units of the area are phyllite, limestone, volcanic rocks of the Cretaceous-Paleocene age, marl, sandstone and shale of the Oligo-Miocene age. Two plutonic complexes of the area are: (1) The granitoid complex of NW Marivan which is composed of syenogranite, monzogranite and granodiorite. Geochemically, these rocks are magnesian alkali-calcic to magnesian calc-alkali, sub-alkaline (calc-alkaline), peraluminous and are S-type. From geochemical and mineralogical aspects, this complex resembles the syn-collision granites. (2) The gabbro-diorite-quartz diorite complex of SE Marivan is composed of various plutonic rocks including gabbro, diorite and quartz diorite. Geochemically, these rocks are sub-alkaline (calc-alkaline), metaluminous, magnesian calcic and are I-type. Rocks of this complex show characteristics of plutonic rocks derived from upper mantle sources. It is worth to note that blocks of I-type complex are surrounded by rocks of S-type complex.