Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Petrology of Gojed Intrusive and Associated Volcanics

Document Type : Original Research Paper

Authors
Mahin Mansouri Esfahani 1
Iraj Norbehesht 2
1 Geology Department, Isfahan University, Isfahan, Iran
2 Faculty of Mining, Isfahan University of Technology, Isfahan, Iran
Abstract
The studied area located about 100 km east of Isfahan and 40 km southwest of Nain. Based on the geochemical data the rocks of area which have injected in volcanic and pyroclastic rocks, are not tonalite (as reported by Geological Survey of Iran), but they are monzogranite.
As a result of contact metamorphism of these rocks with the country rocks, a low-grade Albite- Epidote hornfels facies have been developed. The presence of microgranular enclaves and variable content of SiO2, K2O, CaO, Sr, Rb, Zr, in diffrent facies of the igneous rocks might be an indication of magmatic contamination.
By using different diagrams, all the rocks have calc-alkaline trend with bimodal origin. Basic and acidic rocks have produced from partial melting of mantle and crust respectively.
The granitoids of the region corresponded to Cordilleran type granitiods that have tectonically characterized as plate margin.
Based on overall geochemical and mineralogical studies, it has been concluded that, the plutonic massives have probably produced in continental margin with continental arc magmatic nature, corresponding of the Andean- type. Therefore, these intrusive rocks could be produced in relationship with subduction Neotethys oceanic crust, underneath continental crust of Iran platform.
Keywords
Gojed Intrusive, Volcanics, Nain

Subjects

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Scientific Quarterly Journal of Geosciences
Volume 6, 23-24
Spring & Summer 1998, Vol. 6, No. 23-24
Autumn 1998
Pages 79-95