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        1 - Magmatic interactions as recorded in plagioclase phenocrysts of quaternary volcanics in SE Bam (SE Iran)
        Abdollah Yazdi Afshin Ashja Ardalan Mohammad Hashem Emami Rahim Dabiri Mohammad Foudazi
        In the southeast of Iran (SE Bam), there is a collection of volcanic rocks with andesite, basalt and trachyandesite composition. The textures of these rocks are often porphyritic with microlithic, porphyric cavity, and sometimes glomeroporphyritic, sore throat trachytic More
        In the southeast of Iran (SE Bam), there is a collection of volcanic rocks with andesite, basalt and trachyandesite composition. The textures of these rocks are often porphyritic with microlithic, porphyric cavity, and sometimes glomeroporphyritic, sore throat trachytic. Main minerals include olivine, clinopyroxene, plagioclase and secondary minerals including opaque minerals, Iddingsite, secondary biotite, chlorite and calcite. The analysis of magma textures gives us valuable information about magmatic processes. Micro textures in plagioclase of volcanic rocks in the region are divided into two groups: a) texture-linked to crystalline growth including: sieve texture, oscillatory zoning and degraded surfaces and b) Morphological textures such as glomerular crystals. Sieve texture and zoning in crystal represent processes such as magmatic mixing and abrupt reduction of pressure and, in general, unbalanced conditions in magmatic reservoirs. Based on electron microscope studies, plagioclase of igneous rocks of the region is within the boundaries of labradorite and bytownite.In the southeast of bam, there is a collection of volcanic rocks with andesite, basalt and trachy andesite composition. The texture of these rocks are often porphyritic with microlithic, porphyric cavity, and sometimes glomerulophorphuri, sore throat trachytic. Main minerals include Olivine, Clinopyroxene, Plagioclase and secondary minerals including opaque minerals, Iodenzyte, secondary Biotite, Chlorite and Calcite. Sieve texture and zoning in crystal represent processes such as magmatic mixing and abrupt reduction of pressure and, in general, unbalanced conditions in magmatic reservoirs. Manuscript profile
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        2 - Sedimentological and provenance analysis of the Cretaceous Moro formation Rakhi Gorge, Eastern Sulaiman Range, Pakistan
        Muhammad Khan Shahid Ghazi Mubashir Mehmood Abdollah Yazdi Abbas Ali Naseem Umair Serwar Arsalan Zaheer Hadayat Ullah
        The Cretaceous Moro Formation from the Rakhi Nala section Dera Ghazi Khan has been studied in detail to investigate the Sedimentology and provenance. This paper describes the litho-facies changes, depositional environment, and provenance analysis of the Cretaceous Moro More
        The Cretaceous Moro Formation from the Rakhi Nala section Dera Ghazi Khan has been studied in detail to investigate the Sedimentology and provenance. This paper describes the litho-facies changes, depositional environment, and provenance analysis of the Cretaceous Moro Formation from the Rakhi Nala section, eastern Sulaiman Range. The studied Formation is 110-140 meters thick and consists mainly of fine to coarse-grained sandstone, with minor-siltstone, mudstone (claystone, shale), and limestone. The uppermost beds of the Moro Formation are consist of sandstone with iron types of cement. Twelve lithofacies have been identified based on a petrographic investigation related to the depositional environment of the Moro Formation ranging from deltaic to marine setting (Delta Plain-Delta front). Petrographic analysis of sandstone reveals the presence of quartz both, mono-crystalline and poly-crystalline, less feldspar; heavy minerals like hematite and magnetite, and glauconite were found in negligible amounts. Detrital mineral composition shows that in Moro Formation, the sandstone shows a litharenite. Modal composition of the sandstone from the QFL diagram was Q 66% F 0.3% L 33.7% and that of the QmFLt diagram was QM, 57% F 0.23% L 43.77%. The overall average composition is Q 61.5% F 0.27% L 38.7%. A total of 37 thin-sections are studied for provenance analysis, out of which twenty-seven samples are considered as Litharenite (this shows recycled, or craton interior origin), eight Quartz arenite categories are identified and two samples are fall in the sublitharenites category (Quarts recycled source area). Manuscript profile
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        3 - Petrology and tectono-magmatic environment of the volcanic rocks of West Torud – Iran
        Abdollah Yazdi Elham Shahhosseini Farhad Moharami
        Middle-Upper Eocene volcanic and volcano-sedimentary rocks of the Torud region have been formed by the sequences of basic-intermediate lavas, pyroclastic rocks, and sedimentary layers (e.g., siltstone, sandstone, and nummulite-bearing limestone) within a shallow marine More
        Middle-Upper Eocene volcanic and volcano-sedimentary rocks of the Torud region have been formed by the sequences of basic-intermediate lavas, pyroclastic rocks, and sedimentary layers (e.g., siltstone, sandstone, and nummulite-bearing limestone) within a shallow marine basin. According to microscopic studies, the volcanic rocks of the region include basalt, basaltic andesite, trachyandesite, andesite, and dacite. These rocks have originated from the differential crystallization processes and occasionally calc-alkaline contamination geochemical properties. Generally, they contain olivine, clinopyroxene, and plagioclase ± amphibole minerals. Porphyritic to megaporphyritic textures with microlithic and flow matrixes are observed in these rocks. Studying the main and rare elements of these rocks indicates that reducing MgO content is accompanied by an increase in Al2O3, K2O, Na2O, and SiO2 and a decrease in Fe2O3 and CaO concentrations. These rocks are mainly enriched in LIL and LREE elements but depleted of HFS elements. The prominent features of these rocks are the presence of positive anomalies in the K, Sr, Rb, and Ba elements, the depletion of some samples of Nb and Ta, and their depletion of Ti and P. This result reveals the crustal contamination of the mantle mafic magma constructing these rocks. According to the geochemical data, magmatic pollution has not been an effective process in the formation of these rocks. In addition, the relatively higher levels of Cr, Ni, and MgO in the alkali basalts of the region indicate that these rocks are originated from partial melting (5 to 10%) of a spinel-garnet peridotite. Overall, they have no subduction-dependent rock characteristics and mainly represent characteristics of alkali basaltic magmas of the preliminary back-arc basin (BAB). These features, attributed to their calc-alkaline nature, represent the formation of these rocks in a tectonic back-arc setting in the Middle-Upper Eocene. Manuscript profile
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        4 - Geochemistry and tectonomagmatic environment of Eocene volcanic rocks in the Southeastern region of Abhar, NW Iran
        Masoud Nazari Mohammad Ali Arian Ali Solgi Reza Zareisahamieh Abdollah Yazdi
        Eocene volcanic are exposed in southeast of Zanjan in the Tarom magmatic zone that located in the Central Iran structural zone. The Abhar Eosen pyroclastic with andesite, trachy-andesite, dacite and rhyolite along with tuff compositions is located 120 km southeast of Za More
        Eocene volcanic are exposed in southeast of Zanjan in the Tarom magmatic zone that located in the Central Iran structural zone. The Abhar Eosen pyroclastic with andesite, trachy-andesite, dacite and rhyolite along with tuff compositions is located 120 km southeast of Zanjan. Mineralogically point of view, the studied volcanic rocks have low quartz, negligible alkaline feldspar, abundant plagioclase, and pyroxene contents. Textureally, Porphyritic, microlithic porphyritic, glomeroporphyritic, and poikilitic are predominant in these rocks. All of the studied samples display REE patterns characterized by LREE-enriched (Rb and Ba) and HREE-depleted segments typical of arc lavas which is one of the characteristics of subduction zone. The geochemical characteristics of the studied samples indicated that fractional crystallization is the primary cause of the diversity and differentiation of these rocks compared to crustal contamination. The rocks of the study area are composed of a similar origin to the OIB (mantle components) and partial melting of subcontinental lithospheric mantles. Of course, this mantle source has been modified by recycled sediments and melt released from the edge of the subducting oceanic crust. Manuscript profile