The tectonic setting of Hassanabad-Shojaabad region (northeast Isfahan) based on the tectono-magmatic investigations


1 Associate Professor, Department of Geology, Faculty of Science, Payame Noor University, Tehran, Iran

2 PhD student in Geology, Petrology


Hassanabad-Shojaabad region is located in Urmia-Dokhtar magmatic belt. Regarding the formation of this area, two theories of rifting and subduction have been proposed. In this article, data obtained from desert, petrography, geochemical and magmatic tectonic studies were combined and analyzed. Using several geochemical and magmatic tectonic charts, the type of rocks in the region and the magmatic series of intrusive and volcanic rocks were determined. The intrusive and volcanic rocks in Hassan Abad region are of calc-alkaline type and the result of subtraction of basic magma with the origin of lithospheric mantle, these rocks belong to the subduction tectonic environment in the final stages of expansion of Komani Island. Volcanic rocks and intrusive masses in Shujaabad area are of shoshonite type and are the result of tonalitic melting of the lower crust, these rocks belong to the tectonic environment of the continental arc margin. Therefore, the area under study has been inclined to pressure at the edge of subduction and back arc areas, where Hassan Abad is located in the area of the edge of subduction and Shoja Abad is located in the back arc area.


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