Document Type : Final File

Authors

1 Department of Geology, Faculty of Sciences, University of Payam Noor,Tehran, Islamic Republic of Iran

2 Department of Research and Development (R and D), Pars Kani Co. Tehran, Islamic Republic of Iran

Abstract

Robat-e Zengejeh rocks affected by a variety of events began from Precambrian. This research studied preserved effects of the events. Regional metamorphism is the oldest event in this rocks include schist, amphibolite and orthogneiss, that reached up to amphibolite facies. After this regional metamorphism, it seems that mesocratic (624±5Ma) and hololeucocratic granitoides intruded respectively. Mesocratic and hololeucocratic granitoides deformed to granite-gneiss and gneiss along the northern main fault. Moreover, amphibolites show strong lineation along the faults, which as well as petrographic evidences point to the effects of dynamometamorphism in the area. Meatmorphism followed by low-grade regional metamorphism (low-greenschist facies) affected by granitoids of Robat-e Zengejeh. low-grade regional metamorphism, acted as a retrograde metamorphism for the paragenesis of the previous regional metamorphism. Finally, a sodic metasomatism affected Robat-e Zengejeh  rocks which its mineralogical and geochemical evidences are significant. 

Keywords

Main Subjects

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