Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Tectonomagmatic Environment of Ultramafic –Intermediate Intrusions in Chahghand Complex (South Part of Sanandaj – Sirjan Zone)

Document Type : Original Research Paper

Authors
1 Geology Department, Payam-e-Nour University, Shiraz, Iran
2 Geology Department, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, Iran
Abstract
Chahghand complex is located in the northeast of Neyriz and southwest of Shahre-Babak. This complex consists of granitoid and metamorphic rocks, ultramafic, mafic and intermediate intrusive rocks, inwhich pyroxenite, olivine gabbro and diorite occur.
Alkaline character of the complex is revealed by detailed petrography, geochemistry, multielement patterns (trace and rare earth elements) and tectonomagmatic diagrams. It seems that the generation of these rocks corresponds to the lower degree of partial melting from a lehrzolitic mantle source rock.
The enrichment of LREE, LILE and depletion of HFSE elements coincide with patterns characteristics of intraplate continental setting; as a result, an intracontinental rift environment in Sanandaj-Sirjan zone during Triassic Jurassic for Chahghand complex magmatism is suggested.
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