U-Pb zircon dating, Sr-Nd isotope and petrogenesis of Sarduiyeh granitoid in SE of the UDMA, Iran: implication for the source origin and magmatic evolution. Issue 13 (21st September 2020)

• Record Type: Journal Article
• Authors: Nazarinia, Asma; Mortazavi, Mohsen; Arvin, Mohsen; Hu, Ruizhong; Zhao, Chenghai; Poosti, Mohammad
• Is Part Of: International geology review. Volume 62:Issue 13/14(2020)
• Page Start: 1796
• Page End: 1814
• Publication Date: 2020-09-21
• Subjects: Sarduiyeh granitoid -- UDMA -- Dehaj-Sarduiyeh volcano-sedimentary belt -- U-Pb dating -- fractionation -- Iran; Geology -- Periodicals; Electronic journals; 551.05
• DOI: 10.1080/00206814.2018.1514668
• Languages: English
• ISSNs: 0020-6814

Abstract

ABSTRACT: The Sarduiyeh granitoid (SG) is intruded in the southeastern part of the Dehaj-Sarduiyeh volcano-sedimentary belt in the southeastern end of the Urumieh-Dokhtar Magmatic Arc (UDMA) in Iran. The medium-to-coarse-grained granitoid unit, with granular texture consists mainly of diorite, tonalite, granodiorite and monzogranitic rocks. Mineralogically, these rocks consist mainly of plagioclase, K-feldspar, quartz, biotite and hornblende. The whole rock geochemical analyses indicates that the SG is calc-alkaline, I-type, metaluminous, enriched in large ion lithophile elements (LILE; such as K, Cs, Pb) and depleted in high field strength elements (HFSE; such as Ti, Nb, Ta, Zr). Chondrite normalized plot of SG rare earth elements (REE) show light rare earth element enrichments with (LaN /YbN = 2.44–8.68) and flat heavy rare earth element patterns with (GdN /YbN = 1.02–1.36). The rather high Y ( av . 19.35 ppm), low Sr content ( av . 293.76 ppm) and low Cr and Ni contents ( av . 20.1 and 4.69 ppm, respectively) of the SG demonstrate its normal calc-alkaline and non-adakitic nature, the features of Jebal Barez-type granitoids. The geochemical characteristics and isotopic composition, low ISr (0.7046–0.7049) and positive ɛ t Nd (+3.4 to +4.03) values, of the SG suggest that its parental magma formed as a result of partial melting from metabasic rocks of lower crust in a subduction-related arc setting. Fractionation of an assemblage dominated by plagioclase, K-feldspar, amphibole and magnetite may have been responsible for the evolution of the SG magma. U-Pb zircon geochronology gives an age of 27.95 ± 0.27 Ma for the SG, suggesting that the final collision between the Arabian plate and Central Iranian microcontinent may have happened in the Late Oligocene.