نویسندگان
1 گروه زمینشناسی، دانشکده علوم پایه، دانشگاه بوعلی سینا، همدان، ایران
2 گروه زمین شناسی، دانشکده علوم پایه، دانشگاه بوعلی سینا، همدان، ایران.
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The Gharavol-Khane intermediate-mafic intrusive bodies are located in the northeast of Takht-e Soleiman area (north of Takab) and the northern part of the metamorphic-intrusive Sanandaj-Sirjan zone (SaSZ). These bodies consist of gabbro, diorite, and porphyry granodiorite with Upper Triassic-Middle Jurassic age and are hosted in Precambrian metamorphic basement. This study investigates the whole-rock geochemical data in these intrusions to achieves petrogenesis features, geochemical evolution of magma, and geodynamic setting. The studied intrusions with configuration temperature of 650-800 °C and meta-aluminous nature (A/CNK = 0.5-1.0) belong to calc-alkaline series which show evidence of I-type oxide granitoids (Na2O/K2O = 1.0-2.5) within active continental margin from subduction environments (enrichment of LILE relative to HFSE with depletion of Nb and Ti elements). Mg# values show a gradual decrease from gabbro unit (avg. 15.64 mol%), to diorite unit (avg. 91.60 mol%), and porphyry granodiorite unit (avg. 30.58 mol%). Since I-type oxide granitoids can be adakitic or non-adakitic (normal arc magma) depending on the geodynamic environment and crustal thickening, the binary Rb/Zr vs. Nb and binary Sr/Y vs. Y diagrams were used to distinguish them, and on this basis, the Gharavol-Khane intrusive rocks showed evidence of normal arc magma or non-adakitic affinity. Based on all evidences, the Gharavol-Khane intrusive rocks have higher Th values compared to the mantle melt composition, which is attributed to the release of volatiles due to subduction at the origin or contamination of the metasomatic mantle with melt crust.
کلیدواژهها [English]
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