Mineral chemistry research and a review of petrology of intrusive mass in Mobarak Abad region

Subject Areas :

Ali Asghar Parchegani ¹ , Mohammad Ali Arian ² , Mohammad Fodazi ³

1 - . M.SC Geology, Petrology, Islamic Azad University, North Tehran branch, Tehran, Iran
2 - Department of geology, Islamic Azad University, North Tehran branch, Tehran, Iran
3 - Department of geology, Islamic Azad University, Eslamshar branch, Tehran, Iran

Received: 2020-05-06 Accepted : 2020-05-06 Published : 2015-08-23

Keywords: Petrology, Mobarak Abad, Karaj formation, calc alkaline,

Abstract :

In 75 km of the North-East of Tehran, and in Mobarak Abad region, there is a big dike which is 6km to 500m in the direction West -Northwest and East-Southeast, injected into one of the branches of Mosha-Fasham thrust. This mass is injected into Karaj formation (middle Eocene) so is younger than middle Eocene.  From petrography point of view, the rocks are olivine gabbro, gabbro, diorite and Granodiorite. After electron microprobe analyze (EPMA) of the olivine, pyroxene and plagioclase samples of the area we concluded that olivine with 67.8% Mg is Hyalosiderite, pyroxene is Augite and plagioclase in center is Bytownite and the around is Labradorite. The magma type in this masse is sodic calc-alkaline that has quality metaluminous to peraluminous. Changes of main elements show that the formation elements have a creating relation between terms of plutonic rocks of the region.