Tertiary andesitic basalts of the Sirjan area, Urmieh-Dokhtar Magmatic Arc, Iran, contain plagioclase phenocrysts enclosed in a matrix of amphibole, clinopyroxene and rare olivine crystals. Textural and compositional evidence suggests two significantly different types of plagioclase phenocrysts occur in the andesitic basalts. The most common type of plagioclase phenocrysts have zoning patterns ...

introduction the generation and evolution of granitic magmas has been a hot debated subject among petrologists. the diversity of their origin has led different authors to propose that these rocks are not simple in their origin and might be generated in more ways than one. in the past several decades, many petrologists used a variety characteristics to subdivide the granitoid rocks. such proposa...

The aim of this study is determination and separation of alteration zones using Concentration-Area (C-A) fractal model based on remote sensing data which has been extracted from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images. The studied area is on the SW part of Saveh, 1:250,000 geological map, which is located in Urumieh-Dokhtar magmatic belt, Central Iran. The ...

in the urumieh-dokhtar volcanic zone, there are nearly parallel faults to the zagros zone.they were formed during collision of the arabic plate with central iran plate. the northwest-southeast trending of qom-zefreh fault system has long been recognized as major faults in central iran. the general aim of this research is to identify the activity period of this fault and the extent of its effect...

kalchouyeh area in southwest of naein is located in the urumieh-dokhtar volcano-plutonic belt. mineralization occurred mainly as disseminations and veinlets hosted by trachy-andesite and pyroxene andesites. for mineralogy, alteration, fluid inclusion and geochemical studies, the two major mineralized zones: a (larger vein) from the north-northwest and b (smaller vein) from the east-southeast of...

The Chah-Shur clay deposit is located in150 km southeast of Isfahan. Eocene igneous rocks ‎and Quaternary deposits cover the area. Eocene volcanic rocks include andesite and tuffs ‎which relating to magmatic activities of Urumieh-Dokhtar magmatic belt. Alteration of the ‎vitric and lithic tuff units has produced the clay deposit. Based on the petrographic studies, ‎the main minerals in tuff uni...

The Hezar Igneous Complex (HIC) in the south-eastern part of Urumieh-Dokhtar magmatic arc, is the most prominent magmatic feature in the Kerman Porphyry Copper Belt, that understanding magmatic evolution of which may shed light on the tectonomagmatic development of this less-studied part of an important magmatic arc in the Neotethys realm. The HIC has been developed in the the intersection of t...