Document Type : Original Research Paper

Authors

1 Faculty,of Basis Sciences, Tarbiat Modarres University, Tehran, Iran

2 Geological Survey of Iran, Theran, Iran

3 Department of Geosciences, Naruto University of Education

Abstract

     Kal-e Kafi granitoid complex is a part of Central Iranian structural zone called Yazd block. This complex is composed of a wide spectrum of plutonic rocks ranging from gabbro to alkalike granite with age range of Upper Eocene-Lower Oligocene. Potassic granitoid shows geochemical and mineralogical characteristics distinct from other plutonic rocks in the complex. The potassic granitoids are peralkaline and ferroan while other plutonic rocks in the complex are alkaline to calc-alkaline and magnesian. With respect to REE abundances and patterns, the potassic rocks of the complex are different from other Kal-e Kafi granitoids. Low REE abundances of the potassic granitoids indicate that the rocks could not be related to other plutonic bodies through magmatic differentiation. This would probably demonstrate that different petrogenetic processes were involved in petrogenesis of the potassic granitoids. The potassic granitoids are likely to be the consequence of crustal partial melting.

Keywords

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