Writers : Farsi, Zohreh; Supervisor: Sadeghian, Mahmood
Refference : M.Sc.Thesis-Shahrood University of Technology, Shahrood
Publishing Year : 1386

Abstract :

Chah Salar granitoidic pluton is located in the SW of Neishabour and in the N of Chah-Salar village. Based on the field observations, petrography and geochemical classification diagrams, diorite, quartzdiorite, granodiorite, granite include the lithological composition of this pluton. Granites are very fractionated end-members of this rock association which they are intruded in this pluton such as dike or apophyse.
Granitic pegmatite and tjeir associated quartzolite are the most differentiated end-member of this lithological composition range. Their subvolcanic equivalents such as pyroxene-bearing andessite, andesite, trachyandesite and dacite cut this pluton such as dike or dome. These rocks show a variation of the granular, myrmekitic, graphic, prophyritic, microlitic porphyry and pilotaxitic textures. Except than granites, the other litological compositions, on the variation diagrams of major, trace and rare earth elements versus SiO2 or differentiation represent continuously compositional variations. Variation trends on the compatible and incompatible diagrams versus each other shows that this compositional continunty resulted of fractional crystallization.
Geochemical characteristics show that Chah Salar pluton has calc-alcaline and metaluminous nature and it belongs to I-type granitoids. Discrimination diagrams of the tectonic setting indicate that the Chah Salar granitoidic pluton belong to volcanic arc granitiods (VAG) and also island arc granitoids (IAG). Detailed investigations of field geology, petrography and geochemical characteristics indicate magma-forming of this pluton is resulted from partial melting of subducted amphibolitic oceanic slab or metasomatized mantle wedge and then they evolved by fractional crystallization, magma contamination or magma mixing.

Subject List : granitoide