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Open Journal of Geology 2017年第11期7卷 1644-1653页

作者： Abdollah Yazdi Afshin Ashja-Ardalan mohammad-Hashem emami Rahim Dabiri mohammad Foudazi Department of Geology North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Islamshahr Branch Islamic Azad University Tehran Iran Department of Geology Mashhad Branch Islamic Azad University Mashhad Iran

In this paper, tectonic and geothermobarometric environments have been studied with respect to the combination of pyroxene, olivine and plagioclase in volcanic rocks in the southeast of Bam. The combination of volcanic rocks in the region consists of olivine basalt, basalt, alkaline basalt, andesite, trachyandesite and pyroxene andesite. This combination is the result of the processes of crystallization and sometimes contamination. Plagioclase, clinopyroxene, olivine, and amphibole constitute the major minerals (rock forming minerals) in these rocks. Porphyritic to mega-porphyritic textures with microlithic, glumero-porphyritic and amigdaluidal matrix are observed. Based on the thermometric calculations, plagioclase, pyroxene, and olivine minerals and the rocks of this region are crystallized at a pressure of 1.5 to 7 kb and temperatures ranging from about 700°C to 1250°C.

关键词： Plagioclase Pyroxene Geochemistry Thermo-Barometry Volcanic Rocks Bam

Geodynamics of Dikes in North of Saveh

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Open Journal of Ecology 2015年第9期5卷 452-459页

作者： mohammad-Hasan Bazoobandi mohammad-Ali Arian mohammad-Hashem emami Gholam-Reza Tajbakhsh Abdollah Yazdi Department of Geology Faculty of Science North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Faculty of Science Islamshahr Branch Islamic Azad University Tehran Iran Department of Geology Faculty of Science Yazd University Yazd Iran Department of Geology Faculty of Science Kahnooj Branch Islamic Azad University Kerman Iran

Dikes can be divided into sheeted, feeder, cone and swarm types based on the origin and the formation. A group of dikes that are formed in dense in a relatively broad zone influenced by a particular tectonic regime are referred to as swarm dikes. Swarm dikes have numerous applications such as locating mantle plume centers, determining areas of longstanding tensions and detection of deformation networks. The purpose of this article is classified swarm dikes of “North of Saveh” based on previous studies. In one study, swarm dikes are classified based on their initial geometry into five types of I, II, III, IV and V. According to this classification, our study has been shown that the dikes in north of Saveh are of type IV. In another study, the swarm dikes are classified into three types: parallel, large radial and small radial. According to the classification, our study has been shown that the dikes of North Saveh are parallel that have arisen by tensions caused by the collision of the Arabian plate and the Central Iran plate. In addition to original tensions in the region, local faults have been effective on the arrangement and the establishment of dikes.

关键词： Swarm Dikes Locating Mantle Plume Dikes in North of Saveh Dikes Classification

Mineral Chemistry and Thermobarometry of the Volcanic Rocks in Torud, Iran

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Open Journal of Geology 2014年第9期4卷 425-435页

作者： Elham Shah Hosseini Afshin Ashja Ardalan mohammad Hashem emami mohammad Hossein Razavi Department of Geology North Tehran branch Islamic Azad University Tehran Iran Department of Geology North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Eslamshahr Branch Islamic Azad University Eslamshahr Iran Department of Geology Faculty of Sciences Kharazmi University Tehran Iran

This paper elucidates the compositional studies on clinopyroxene, plagioclase of basalts to andesitic rocks of Torud area to understand the geotectonic and geothermobarometry conditions.?Early?Eocene-Oligocene calc-alkaline volcanic rocks are exposed around Torud in the Central Iranian zone. Volcanic rocks consist of basaltic, andesite basalt, Tracyandesite, and andesite. Minerals in the volcanic rocks exhibit degrees of disequilibrium features. Plagioclase as dominant mineral in these rocks generally displays oscillatory zoning. Mineral chemistry studies show that clinopyroxenes in the volcanic rocks are diopside, augite and plotted in medium pressure field. The clinopyroxene composition yields the crystallization temperatures 900°C?- 1000°C. The mineral composition indicates that these rocks are formed in a tensional environment.

关键词： Volcanic Rocks Mineral Chemistry Clinopyroxenes Plagioclase Torud

Formation of Extensional Basin in Internal Part of the Zag-Ros Orogeny in West of Sirjan, Iran

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Open Journal of Geology 2015年第11期5卷 821-827页

作者： Amin Azadikhah Soheila Bouzari Ali Yassaghi mohammad Hashem emami Department of Geology North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Tarbiat Modares University Tehran Iran Department of Geology IslamShar Branch Islamic Azad University Islamshhar Iran

Oblique continent—continent collision between Iranian microcontinent and Arabian plate is the main cause of transpression and transtension regimes in this area. Zagros orogeny in this area resulted in formation of various structures including thrust fault-related folds, dextral and sinistral, strike slip faults, normal fault related to dextral strike slip fault. Thrust faults within the area under study are duplex with general trend of NW-SE and dip toward the north-east with right slip component. Strike slip fault regime acts as tear fault and it is active yet. Therefore, simultaneous presence of thrusts and strike slip faults illustrates convergent dextral transpressional tectonic regime while this transpressional regime accompanied with transtension as well;since normal faults are also seen in alluvium around depression of Sirjan which can be as a result of extension stresses due to strike slip faults activity of the district. The results achieved from geometry and kinematic analysis of west of Sirjan structures indicate that structures of the area have characteristics of internal part of Zagros orogeny.

关键词： Zagros Orogeny Thrust Faults Transpression Strike Slip Faults

Geochemistry and Petrogenesis of Intrusive Pluton in North of Golpayegan (Central Part of Sanandaj-Sirjan Zone)

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Open Journal of Geology 2014年第9期4卷 481-494页

作者： Marzieh Shahpari Afshin Ashja Ardalan mohammad Hashem emami mohammad Ali Arian Abdollah Yazdi Department of Geology Faculty of Sciences North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Eslamshahr Branch Islamic Azad University Eslamshahr Iran Department of Geology Kahnooj Branch Islamic Azad University Kerman Iran

Granitoid pluton in the north of Golpayegan is located in10 kmnorth of Golpayegan at SanandajSirjan zone. Dominant rocks of this region include granite, syenite, and gabbro. Granite type is granular with medium to coarse crystals and its mineralogical composition contains alkali feldspar + quartz + plagioclase + biotite + secondary minerals (opaque + sphene + apatite). Granite rocks have calc-alkaline and?metaluminous to peraluminous nature, relative enrichment of Rb over Sr, and relative enrichment of LILE over HFSE elements. These granites, which are type I, are derived from the melting of metagreywackes and their tectonic setting is of upper continental crust and post-orogenic setting. Gabbroic type is older than other types of the pluton and is granular with medium to fine crystal. Mineralogical composition of these rocks is plagioclase + pyroxene + amphibole + biotite + secondary minerals (opaque). Based on geochemical characteristics of tholeiitic and metaluminous nature, relative enrichment of Ba and Sr elements over Rb, relative enrichment of LILE elements over HFSE, negative anomaly of Nb, Ba, and Ta, and positive anomaly of Pb are observed. Origin of this type is probably from enriched mantle and in-plane tectonic setting.

关键词： Granitoid Sanandaj-Sirjan Zone Golpayegan

Geochemistry and Tectonic Setting of Kohe Siahvolcanoes, North Qorveh, Sanandaj, Iran

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Open Journal of Geology 2018年第5期8卷 474-488页

作者： Somaye Kazemi Koohbanani Seyed Jamal Sheikhzakariee mohammad Hashem emami Rahim Dabiri Department of Geology Science and Research Branch Islamic Azad University Tehran Iran Department of Geology Islamic Azad University Islamshahr Branch Tehran Iran Department of Geology Islamic Azad University Mashhad Branch Mashhad Iran

The KoheSiah Volcanoes are located in the North of Qorveh city in the west of Iran. The KoheSiah volcanoes include several craters bearing domes located in the Kordestan Province, between latitudes 35°23'13.54” to 35°21'26.63”N and longitudes 47°54'38.26”E to 47°56'01.42”E. Based on the petrographic and geochemical analysis, the volcanic rocks in the KoheSiah area are classified as basalt, Alkali basalt, trachy-andesites and mugearite. The studied samples are alkaline with sodic to potasic feature based on Na2O/K2O ratios and belonging to Shoshonite series. Most of the alkaline volcanic rocks in the study area fall in the field of within in plate basalts (WPB) and represent of a mantle metasomatism trend associated with variable degrees in the partial melting of an enriched mantle source.

关键词： Alkaline Rocks Kohesiah Volcanoes Dome Qorveh Tectonic Setting

Petrography, Temperature Measurement, and Economic Evaluation of Granitoid Pluton of Qohrud-Kashan Using EPMA, XRD, and XRF Analysis

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Open Journal of Geology 2014年第8期4卷 406-424页

作者： Afshin Ashja Ardalan Mina Khodadady mohammad Hashem emami Jamal Sheikh Zakariaie mohammad Hosein Razavi Abdollah Yazdi Department of Geology Faculty of Sciences Islamic Azad University North Tehran Branch Tehran Iran Department of Geology Faculty of Sciences Islamic Azad University Science and Research Branch Tehran Iran Department of Geology Faculty of Sciences Kharazmi University Tehran Iran Department of Geology Islamic Azad University Islamshahr Branch Islamshahr Iran Department of Geology Islamic Azad University Kahnooj Branch Kerman Iran

The area which is being studied is located in northwest of Isfahan, 30 kilometers south of Kashan, and southern section of Qmasar. The longitude of the area of study is 51°19'13"E to 51°26'26"E and its latitude is 33°34'24"N to 33°44'24"N. Based on microscopic observations, modal analysis, and also based on their location in the Streckeisen [QAPF], both the stones of the Qohrud batholitic mass themselves and its enclaves are more in quartz monzonite ranges. Granitoid also have quartz monzonite enclaves. These enclaves are from both microgranular mafic and Autolith types which indicate the mixing of two magmas. At the center of the pluton, there are indications of existence of main magma reservoir and magma mixing. In terms of mineralogy, the granitoid rocks of the area very much resemble I-type. The zoning of the plagioclases is both the normal kind and variation invert and has andesine general composition. The probed biotite sample contains iron and belongs to a granitic sample from the center of the mass. Also, the ranking graph indicates biotite as the source of recrystallization for the analyzed points. The probed biotite sample of the Qohrud area showed formation temperature of 730 degrees centigrade. According to the Rb and Sr contents, the source of the rocks is at depths of 20 to 30 kilometers from the earth’s surface that are depending on the subduction zone. The formation temperature of the specimens of the Qohrud batholithic mass is mostly between 900 to 1000 degrees centigrade. [At] the center of the mass (around Qahrud), the amount of molybdenum is higher than the economic limit.

关键词： Kashan Qohrud Granitoid Temperature Measurement Analysis

Petrology and Tectonic Setting of Volcanic Rocks in West and South West of Salafchegan, Qom, Iran

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Open Journal of Geology 2017年第6期7卷 745-767页

作者： Mozhgan Taheri Afshin Ashja Ardalan mohammad Hashem emami Seyed Jamal Shaikh Zakariay Department of Geology North Tehran Branch Islamic Azad University Tehran Iran Department of Geology Islamshahr Branch Islamic Azad University Tehran Iran Department of Geology Science and Research Branch Islamic Azad University Tehran Iran

In the west and south-west part of Salafchegan near Zavarian village in Iran (in central Iranian volcano plotonic belt), there are some volcanic rocks. Based on petrography and geochemistry findings, these volcanic rocks are Basalt, Andesite, Tracky-Andesite, Trackyte, Latite, Dacite. Tectono-magmatic diagram Y versus Zr shows the magmatic arc setting and Zr/TiO2 versus Ce/P2O5 diagram contrasts post colligenal magmatic arcs. The HFSE depletion in the MORB spider diagram shows significant volcanic arc magmatism. The high enrichment of Eu, Sr, Th, Rb, Cs, K (LFS elements) and Y, Zr, Hf shows negative anomaly and subduction tectonic setting. Based on MORB, Chondrite and primitive mantle spider diagrams, LREE have enriched to HREE in this area. The results of petrography, geochemistry and tectonic setting studies in this area, indicate that neogene magmatism occurred in post colligenal tectonic setting—subduction of Neo-thetise ocean under central Iranian plate in neogen era.

关键词： Volcanic Rocks Andesite Central Iranian Volcano Plotonic Belt Salafchegan Iran

Geology of the Aftabrou Polymetallic Deposit, Saveh, Iran

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Open Journal of Geology 2017年第7期7卷 978-999页

作者： Akram Sabzian Fariborz Masoudi Hooshang Asadi-Harooni mohammad-Hashem emami Nima Nezafati Department of Geology Science and Research Branch Islamic Azad University (IAU) Teheran Iran Faculty of Earth Sciences Shahid Beheshti University Evin Tehran Iran Department of Mining Engineering Isfahan University of Technology Isfahan Iran Department of Geology Islamshahr Branch Islamic Azad University Teheran Iran

Aftabrou polymetallic prospect is located at the contact of Oligo-Miocene calcalkaline granodioritic to dioritic and Eocene andesitic to basaltic volcanic complex in middle section of Urumiyeh-Dokhtar volcanic arc in NW of Saveh city. Petrographic study indicated that the volcanic rocks are mostly: lava and tuff. Composition of lavas is mainly andesite and tuffs are mainly composed of dacite to rhyodacite. Major phenocrysts in these rocks are plagioclase, clinopyroxene, hornblende and opac minerals. Petrographic and geochemical studies indicated an I-type granitoid and, calcalkaline magmatism associated with continental margin of subduction zone. This study determined three mineralization subzones of 0.2% - 5.3% Cu, 0.02 - 1.31 ppm Au and 1.2% - 3.9% Zn. Fluid inclusion studies on quartzic veins associated with magmatism, demonstrated that homogenization temperatures of this mineralization fluid are between 170°C to 330°C, the salinity of the system is between 11.7 to 23.5 weight percent, density of this fluid is 0.8 - 1.1 g/cm3 and is occurred in depth of less than 1800 m of surface. Fluid inclusion studies suggested that formation of mineral deposit is simple cooling and mixing with atmospheric water and type of Aftabrou deposit is IOCG. In this base, it is assumed that this IOCG mineralization is occurred associate with magmatism that is formed as a result of Neo-Tethys oceanic subduction beneath the Central Iran zone which is replaced in the Orumieh-Dokhtar magmatic arc.

关键词： Aftabrou Polymetallic Mineralization Calcalkaline Fluid Inclusion IOCG Deposit

The Petrography, Mineralography and Microprobe Analysis on New Exploratory Excavation Phase in Sarcheshmeh Copper Mine Pit and Comparing Them with Existing Data from the Other Area in South West Sarcheshmeh

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Open Journal of Geology 2017年第2期7卷 162-181页

作者： Mehdi Abdollahy Riseh Mansur Vosooghi Abedini mohammad Hashem emami Seyed Jamal Sheikh Zakariaei Department of Geology Science and Research Branch Islamic Azad University Tehran Iran

Kerman region where Sarcheshmeh zone is located includes the end part of Uremia-Dokhtar Zone. Extrusive igneous group in Sarcheshmeh is as follows: 1) andesite and 2) rhyodacite. The group of intrusive igneous rocks includes 1) porphyry granite, 2) porphyry granodiorite, and 3) porphyry diorite. Nochoon mine is located at 4 km of southwest of Sarcheshmeh copper mine and it comprises of a group of extrusive igneous rocks as follows: 1) andesite, and 2) dacite. Based on results of microprobe analysis, pyroxene mineral’s composition in these rocks of diopside and augite indicates amphiboles of composite zone of magnesium hosting type and existing plagioclases in regional rock for labradorite and bitonit composition. The most common compounds are chlorite with formula among antigorite and amosite. Comparison of magnetite mineralization in Sarcheshmeh and Nochoon indicates vein mineralization in Nochoon and disseminated granulation in Sarcheshmeh and particularly concerning to chalcopyrite, Nochoon includes more veins than Sarcheshmeh.

关键词： Petrography Microprobe Chemical Analysis Sarcheshmeh Mine Kerman