Adakite signatures in granitoids northwest of Shahr-e-Babak, Kerman, Iran: constraints from geochemistry

Granitoid bodies are intruded in the northwestern part of the Dehaj-Sarduiyeh volcano-sedimentary belt, southeast of the Urumieh-Dokhtar Magmatic Arc in Iran. These rocks, with porphyritic texture consist mainly of diorite, tonalite and granodiorite rocks. Mineralogically, they consist mainly of plagioclase (andesine and oligoclase), K-feldspar (orthoclase), quartz, biotite and magnesio-hornblende. Whole rock geochemical analyses reveal subalkaline, calc-alkaline, metaluminous and I-type characteristics. The studied granitoids are enriched in LILEs (such as K, Cs, Sr, Pb) and depleted in HFSEs (such as Ti, Nb, P) similar to granitoids found at subduction zones. The geochemical characteristics of the studied granitoids such as their low Y (av. 8.80 ppm) content, high Sr content (av. 891 ppm), Sr/Y > 20 (av. 102) and no significant Eu anomalies, indicate their similarity with adakitic magma (Kuh-Panj type). The geochemical characteristics of the studied granitoids show their derivation from partial melting of a thickened, garnet bearing, amphibolitic lower continental crust in a subduction-related arc setting.

Automated summary

Granitoid bodies in the northwestern part of the Dehaj-Sarduiyeh volcano-sedimentary belt in Iran consist mainly of diorite, tonalite, and granodiorite rocks. Geochemical analyses suggest that they originated from the partial melting of the lower continental crust in a subduction-related arc setting, similar to adakitic magma.