Petrography, geochemistry and tectonic setting of the Kuh Gabbri granitoide, Rafsanjan,
Subject Areas :
Keywords: : Crustal melting Fractional crystallization Kuh- gabbri granitoid Rafsanjan,
Abstract :
The Kuh-Gabbri granitoid is located at 42 Km east of Rafsanjan in Kerman provinc. This region is small part of Urumieh- Dokhtar magmatic belt of Iran. Intrusive of two granitoid stocks into upper Crataceous limestone and lower Paleocene polygenetic conglomerate, produced contact metamorphism. These rocks contain major minerals such as Quartz, Alkali feldspar and Plagioclase; minor minerals as Biotite, Zircon and Opaque. The SiO2 contents range from 75.57 to 76.83 wt%. The majority of the Kuh-e- Gabbri rocks show similar patterns in the trace element plot normalized to primitive mantle and condrite. These rocks are generally enriched in Rb and Th, and depleted in Ba, Sr and Eu. Condrite- normalized REE patterns are moderately LREE enriched white pronounced negative Eu anomalies. The Nb anomaly implies a crustal component. Moreover all data belong to the within- plate granite fild in the tectonic discrimination diagram and those are I- type granite. Felid, petro raphic and geochemical characteristics suggest magmatic origin and crustal source rock under low pressure conditions. Petro raphic and chemical variations were mainly the result of fractional crystallization.