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 ...

in order to study biostratigraphy of the surgah formation in zagros sedimentary basin, two subsurface sections of this formation in maleh kuh and sarkan oil fields at pol-e-dokhtar area, lorestan province, have been selected. the thickness of surgah formation at maleh kuh and sarkan, was 82 and 46 meters respectively and is composed of shale with intercalation of limestone and calcareous shale....

volcanic rocks of interest are situated in the middle part of the urumieh-dokhtar magmatic arc (udma). they are parts of a vast magmatic province located in the north of bitlis-zagros suture zone. having a prevailing porphyritic texture, these rocks include phenocrysts of plagioclase, amphibole and biotite in a matrix composed of feldspar, quartz, opaque, glass and microlite and mineralogically...

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 ...

homogeneity and uniformity of soil particles is a most potent factor which affects soil spectral signatures. geometric standard deviation of soil particles (?g) exhibits the homogeneity of soil components. this study presents the influence of ?g on spectral studying of soil geometric mean particle diameter as well as lime. the study was conducted in pol-e-dokhtar using the data set of lissiii-p...

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...

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...

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...