Bu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Type and genetic model of mineralization in the Qoushebolaq Pb-Zn occurrence (NW Zanjan): Evidence from geology, mineralization, and geochemistryType and genetic model of mineralization in the Qoushebolaq Pb-Zn occurrence (NW Zanjan): Evidence from geology, mineralization, and geochemistry123569610.22084/nfag.2024.29498.1619FASh.TarvirdizadehM. Sc. student, Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran0009-0007-7618-0860H.KouhestaniAssoc. Prof., Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran0000-0002-3031-9042M. A. A.MokhtariAssoc. Prof., Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran0000-0002-5359-416XN.RahmatiM. Sc. student, Dept., of Geology, Faculty of Sciences, University of Zanjan, Zanjan, Iran0009-0008-0113-2319Journal Article20240617The Qoushebolaq Pb-Zn occurrence, located 110 km northwest of Zanjan, is part of the Tarom-Hashtjin metallogenic belt. The mineralization occurred as a 200-meter long and 1-to-2-meters wide Pb-Zn-bearing quartz-sulfide vein (NE-SW/70-80NW) hosted by Eocene volcanic and volcaniclastic strata and is enclosed by 3-to-5-meters intermediate argillic alteration halos. Hydrothermal alteration in the study area comprises silicification, carbonate, intermediate argillic, and propylitic alteration. Pyrite, chalcopyrite, galena, sphalerite, pyrolusite, and psilomelane are ore minerals, and quartz, calcite, siderite, and sericite-illite are gangue minerals. Cerussite, smithsonite, malachite, covellite, and goethite are formed during supergene processes. The ore minerals formed as disseminated, vein-veinlets, brecciated, crustiform, colloform, cockade, bladed, plumose, vug infill, and replacement textures. Five mineralization stages can be distinguished at Qoushebolaq, where Pb-Zn mineralization occurred as quartz-pyrite-chalcopyrite-galena-sphalerite veins and breccias in the second stage. The Chondrite-normalized trace elements and REE patterns of ore samples, and host crystal tuff are comparable. This reveals that alteration and leaching of elements from the host volcanic and volcaniclastic are involved in mineralization. According to all the evidence, the mineralogical characteristics of the Qoushebolaq occurrence are similar to the intermediate-sulfidation type of epithermal deposits.The Qoushebolaq Pb-Zn occurrence, located 110 km northwest of Zanjan, is part of the Tarom-Hashtjin metallogenic belt. The mineralization occurred as a 200-meter long and 1-to-2-meters wide Pb-Zn-bearing quartz-sulfide vein (NE-SW/70-80NW) hosted by Eocene volcanic and volcaniclastic strata and is enclosed by 3-to-5-meters intermediate argillic alteration halos. Hydrothermal alteration in the study area comprises silicification, carbonate, intermediate argillic, and propylitic alteration. Pyrite, chalcopyrite, galena, sphalerite, pyrolusite, and psilomelane are ore minerals, and quartz, calcite, siderite, and sericite-illite are gangue minerals. Cerussite, smithsonite, malachite, covellite, and goethite are formed during supergene processes. The ore minerals formed as disseminated, vein-veinlets, brecciated, crustiform, colloform, cockade, bladed, plumose, vug infill, and replacement textures. Five mineralization stages can be distinguished at Qoushebolaq, where Pb-Zn mineralization occurred as quartz-pyrite-chalcopyrite-galena-sphalerite veins and breccias in the second stage. The Chondrite-normalized trace elements and REE patterns of ore samples, and host crystal tuff are comparable. This reveals that alteration and leaching of elements from the host volcanic and volcaniclastic are involved in mineralization. According to all the evidence, the mineralogical characteristics of the Qoushebolaq occurrence are similar to the intermediate-sulfidation type of epithermal deposits.https://nfag.basu.ac.ir/article_5696_b8cfbf77a3d250a4523ba67a65a7d031.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Numerical modeling of the effectiveness of some geogrid parameters in reducing the settlement of the foundation placed on granular soilNumerical modeling of the effectiveness of some geogrid parameters in reducing the settlement of the foundation placed on granular soil2442560910.22084/nfag.2024.29195.1610FAA.JamshidiAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranR.YazarlooAssist. Prof., of Civil Engineering, Islamic Azad University, Gonbad Kavoos branch, Gonabad Kavoos, Iran0000-0002-8742-5663S.AligholiDept., of Engineering Geology, Institute of Innovation, Science and Sustainability, Federation University, Ballarat 3350, VIC, AustraliaF.NabizadehAssist. Prof., of Civil Engineering, Islamic Azad University, Chaloos branch, Chaloos, IranJournal Article20240408Reinforcement can significantly reduce foundation settlement, but finding an economic plan requires detailed numerical studies. In the present study, the stability of granular soil reinforced with geogrid was analyzed using PLAXIS software and the effect of factors such as the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid on the of settlement were investigated. The results indicate that the factors mentioned above play a significant role in the foundation settlement. The analysis shows that by increasing the number and length of geogrid, the settlement value has decreased. Moreover, with the increase in the tensile strength of the geogrid, the settlement has significantly reduced. In regard the depth of the reinforced area, it was found that placing the first layer of geogrid after a certain depth (optimal depth) below the foundation does not cause a noticeable reduction in the settlement. Based on the output of PLAXIS software, the optimal values of the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid layer to minimizing the amount of settlement have been proposed. This can lead to a reduction in the costs of foundation design and implementation. According to the results, the lowest settlement (41 mm) was for the conditions where 5 layers of geogrid were used. The most optimal geogrid length and depth of the first geogrid layer to reduce the settlement is equal to 2.5 and 0.5 times the foundation width, respectively. Also, the lowest settlement (80.5 mm) for geogrid with tensile strength of 4500 kN/m was obtained. Finally, the accuracy of the results has been checked based on the modeling of actual data published by Laviza et al. (2010).Reinforcement can significantly reduce foundation settlement, but finding an economic plan requires detailed numerical studies. In the present study, the stability of granular soil reinforced with geogrid was analyzed using PLAXIS software and the effect of factors such as the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid on the of settlement were investigated. The results indicate that the factors mentioned above play a significant role in the foundation settlement. The analysis shows that by increasing the number and length of geogrid, the settlement value has decreased. Moreover, with the increase in the tensile strength of the geogrid, the settlement has significantly reduced. In regard the depth of the reinforced area, it was found that placing the first layer of geogrid after a certain depth (optimal depth) below the foundation does not cause a noticeable reduction in the settlement. Based on the output of PLAXIS software, the optimal values of the number and length of geogrid layers, the optimal depth of the first geogrid layer below the foundation, and the tensile strength of the geogrid layer to minimizing the amount of settlement have been proposed. This can lead to a reduction in the costs of foundation design and implementation. According to the results, the lowest settlement (41 mm) was for the conditions where 5 layers of geogrid were used. The most optimal geogrid length and depth of the first geogrid layer to reduce the settlement is equal to 2.5 and 0.5 times the foundation width, respectively. Also, the lowest settlement (80.5 mm) for geogrid with tensile strength of 4500 kN/m was obtained. Finally, the accuracy of the results has been checked based on the modeling of actual data published by Laviza et al. (2010).https://nfag.basu.ac.ir/article_5609_828c3938b662961ed8f775ed638b97f2.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Petrology, mineral chemistry, and thermobarometry of the metamorphic rock assemblages in north AznaPetrology, mineral chemistry, and thermobarometry of the metamorphic rock assemblages in north Azna4359563210.22084/nfag.2024.29524.1620FAM.TahmasbiPh. D. student. Dept., of Geology, Faculty of Science, Bu Ali Sina University, Hamedan, IranA. A.Sepahi GerowProf., Dept., of Geology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran,
Prof., Dept., of Geology, Faculty of Science, Bu Ali Sina University, Hamedan, IranM. M.MiriAssist. Prof., Dept., of Geology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, IranJ.IzadyarAssoc. Prof., Dept., of Geology, Faculty of Science, University of Zanjan, Zanjan, IranJournal Article20240413North Azna (the Sanandaj-Sirjan zone) hosts metamorphic complex including slate, phylite, andalsuite staurolite schist, hornfelse, marble and meta-sandstone formed by various metamorphism and deformation phases during subduction of Neo-Tethys beneath in the Jurassic. Electron microprobe analyses show that the garnets are almandine-rich, the biotites are high-Mg, the plagioclases are of albite and the chlorites are Fe-Mg rich. Petrographic observations reveal that the mineral assemblage garnet + staurolite + biotite + andalusite formed in the schists at peak of the regional metamorphism in the middle amphibolite facies. After that and due to intrusion of the granitoid bodies, the second metamorphism phase formed the garnet + biotite + andalusite hornfelse. The rocks subsequently endured retrograde metamorphism caused substitution of the staurolite and andalusite with the biotite + muscovite + chlorite assemblage. The calculated thermodynamic phase diagram show that the regional metamorphism reached 550 °C and 4 kbar at its peak condition. In the contact metamorphism, increasing temperature caused formation of more andaluite in the hornfelses. Although, Al2O3 content of the protolith was not sufficient to form high amounts of andalusite.North Azna (the Sanandaj-Sirjan zone) hosts metamorphic complex including slate, phylite, andalsuite staurolite schist, hornfelse, marble and meta-sandstone formed by various metamorphism and deformation phases during subduction of Neo-Tethys beneath in the Jurassic. Electron microprobe analyses show that the garnets are almandine-rich, the biotites are high-Mg, the plagioclases are of albite and the chlorites are Fe-Mg rich. Petrographic observations reveal that the mineral assemblage garnet + staurolite + biotite + andalusite formed in the schists at peak of the regional metamorphism in the middle amphibolite facies. After that and due to intrusion of the granitoid bodies, the second metamorphism phase formed the garnet + biotite + andalusite hornfelse. The rocks subsequently endured retrograde metamorphism caused substitution of the staurolite and andalusite with the biotite + muscovite + chlorite assemblage. The calculated thermodynamic phase diagram show that the regional metamorphism reached 550 °C and 4 kbar at its peak condition. In the contact metamorphism, increasing temperature caused formation of more andaluite in the hornfelses. Although, Al2O3 content of the protolith was not sufficient to form high amounts of andalusite.https://nfag.basu.ac.ir/article_5632_a2232b5b6b17429cdff8ddc2f14ea8c9.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Biostratigraphy of Permo-Triassic succession at the Abadeh area, North of Fars ProvinceBiostratigraphy of Permo-Triassic succession at the Abadeh area, North of Fars Province6078564510.22084/nfag.2024.29104.1609FAH.NoroozpourAssist. Prof., Dept., of Geology, Faculty of Science, Payame Noor University, Tehran, Iran0000-0003-2293-3904M.Yousefi RadAssoc. Prof., Dept., of Geology, Arak University of Technology, Arak, IranM.ArianProf., Faculty of Converging Sciences and Technologies, Islamic Azad University, Science and Research Branch, Tehran, IranA.SolgiAssoc. Prof., Faculty of Converging Sciences and Technologies, Islamic Azad University, Science and Research Branch, Tehran, IranJournal Article20240314In this research, Permo-Triassic boundary was studied in three stratigraphic sections at Abadeh area (Fars Province). For microfossils identification, was taken 170 samples from limestone strata (for foraminifera and algae) and 15 fine-grained clastic samples (for palynomorph identification) from upper parts of the Abadeh fm., the Hambast fm., and lower parts of the Elika Fm. (equivalent deposits). The study of thin sections and palynological slides led to identification of 48 species belong 43 genera of foraminifera and algae and 7 species belong to 6 genera of palynoflora.<br />Based on appearance and stratigraphy range of foraminifera in the upper parts of the Abadeh fm., four biozone including Frondina permica-Climacammina grandis Range Zone, Climacammina grandis-Chusenella sinensis Range Zone, Cribrogenerina sumatrana-Frondina permica Range Zone, Frondica permica Range Zone were proposed to early Julfian (early Wuchiapingian). In Hambast formation, based on foraminifera stratigraphic range three biozone including Tauridia nudiseptata Range Zone, Nodosinelloides mirabilis Range Zone, Globivalvulina vonderschmiti Range Zone were identified and base ond palynoflora stratigraphic range in this formation, was introduced informally an assemblage zone A and for these deposits was suggested late Julfian-Durashamian (late Wuchiapingian- Changhsingian). In equivalent deposits of Elika Formation was identified foraminifera (Globivalvulina Vonderschmiti) and palynomorphs (Alisporutes sp., Falcisporites sp.), spore and fungi. Based on stratigraphic range of palynoflora, was introduced an informal biozone assemblage zone B. Based on presence of fungal spores, the same dip, gradational of Permian-Triassic deposits boundary and absence of retrogradation and unconformity evidences, for equivalent deposits of Elika Formation was suggested Early Triassic (Induan). In this research, introduced biozones, have well correlation with introduced biozones from another region of the Iran and world.In this research, Permo-Triassic boundary was studied in three stratigraphic sections at Abadeh area (Fars Province). For microfossils identification, was taken 170 samples from limestone strata (for foraminifera and algae) and 15 fine-grained clastic samples (for palynomorph identification) from upper parts of the Abadeh fm., the Hambast fm., and lower parts of the Elika Fm. (equivalent deposits). The study of thin sections and palynological slides led to identification of 48 species belong 43 genera of foraminifera and algae and 7 species belong to 6 genera of palynoflora.<br />Based on appearance and stratigraphy range of foraminifera in the upper parts of the Abadeh fm., four biozone including Frondina permica-Climacammina grandis Range Zone, Climacammina grandis-Chusenella sinensis Range Zone, Cribrogenerina sumatrana-Frondina permica Range Zone, Frondica permica Range Zone were proposed to early Julfian (early Wuchiapingian). In Hambast formation, based on foraminifera stratigraphic range three biozone including Tauridia nudiseptata Range Zone, Nodosinelloides mirabilis Range Zone, Globivalvulina vonderschmiti Range Zone were identified and base ond palynoflora stratigraphic range in this formation, was introduced informally an assemblage zone A and for these deposits was suggested late Julfian-Durashamian (late Wuchiapingian- Changhsingian). In equivalent deposits of Elika Formation was identified foraminifera (Globivalvulina Vonderschmiti) and palynomorphs (Alisporutes sp., Falcisporites sp.), spore and fungi. Based on stratigraphic range of palynoflora, was introduced an informal biozone assemblage zone B. Based on presence of fungal spores, the same dip, gradational of Permian-Triassic deposits boundary and absence of retrogradation and unconformity evidences, for equivalent deposits of Elika Formation was suggested Early Triassic (Induan). In this research, introduced biozones, have well correlation with introduced biozones from another region of the Iran and world.https://nfag.basu.ac.ir/article_5645_6f6d7ea73f8b34354a3ecc69f872abfd.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Geochemistry and petrogenesis of the granitoid rocks in Mahiroud volcano-plutonic complex; Southeast of Sarbisheh (Eastern of Iran)Geochemistry and petrogenesis of the granitoid rocks in Mahiroud volcano-plutonic complex; Southeast of Sarbisheh (Eastern of Iran)7996570110.22084/nfag.2024.29210.1612FAA.DavodiM. Sc., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranA.Ahmadi KhalajiAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranSh.KeshtgarAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranP.EskandarniaM. Sc., of Geology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, IranZ.TahmasbiAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranJournal Article20240413The study granitoid pluton is a part of the Mahiroud (Cheshmeh Ostad) volcano-plutonic complex in the southeast of Sarbisheh (South Khorasan province). The composition of this pluton is mostly granodiorite-tonalite. Its main minerals include plagioclase, quartz, orthose and hornblende with granular texture. Based on mineral chemistry, amphiboles in these rocks have a calcic composition and are placed in the Mg-hornblende subgroup. These amphiboles crystallized under pressure conditions of 0.5 to 2 kbar, temperature between 700 - 725 ºC and high oxygen fugacity. Based on the geochemical results, this granitoid pluton is in the range of type I, metalunimous and calc-alkaline granites. Also, this puloton is been formed through mantle partial melting so that La and Dy increase with the increase of La/Sm and Dy/Yb ratios. These rocks were formed through partial melting and less than 5% of sediments have been subducted and fluid has entered the magma source. The spider diagram of trace elements normalized with the primary mantle shows relative enrichment with a gentle slope of LREE elements compared to HREE. This granitoid pluton is similar to subduction-related granites and is consistent with the calc-alkaline magmatic arc in the eastern of Iran which is the result of the subduction of the Neotethys oceanic plate (Sistan Ocean) under the eastern zone of Iran.The study granitoid pluton is a part of the Mahiroud (Cheshmeh Ostad) volcano-plutonic complex in the southeast of Sarbisheh (South Khorasan province). The composition of this pluton is mostly granodiorite-tonalite. Its main minerals include plagioclase, quartz, orthose and hornblende with granular texture. Based on mineral chemistry, amphiboles in these rocks have a calcic composition and are placed in the Mg-hornblende subgroup. These amphiboles crystallized under pressure conditions of 0.5 to 2 kbar, temperature between 700 - 725 ºC and high oxygen fugacity. Based on the geochemical results, this granitoid pluton is in the range of type I, metalunimous and calc-alkaline granites. Also, this puloton is been formed through mantle partial melting so that La and Dy increase with the increase of La/Sm and Dy/Yb ratios. These rocks were formed through partial melting and less than 5% of sediments have been subducted and fluid has entered the magma source. The spider diagram of trace elements normalized with the primary mantle shows relative enrichment with a gentle slope of LREE elements compared to HREE. This granitoid pluton is similar to subduction-related granites and is consistent with the calc-alkaline magmatic arc in the eastern of Iran which is the result of the subduction of the Neotethys oceanic plate (Sistan Ocean) under the eastern zone of Iran.https://nfag.basu.ac.ir/article_5701_bac49b876d5dfc9cd169c22ef5178ca7.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Structural and tectonical study and nomination of Bozgush fold and thrust belt (NW Iran)Structural and tectonical study and nomination of Bozgush fold and thrust belt (NW Iran)97116578010.22084/nfag.2024.15973.1600FAB.ZamaniAssoc. Prof., Dept., of Earth Sciences, Natural Sciences Colleague, University of Tabriz, Tabriz, Iran,
Invited researcher on University of Strasbourg, CNRS UMR7063 – ITES, 5 Rue Ren´e Descartes, F-67084, Strasbourg Cedex, FranceY.KarimiM. Sc. (graduated), Dept., of Earth Sciences, Natural Sciences Colleague, University of Tabriz, Tabriz, IranJournal Article20240513Bozgoush Mountains located in northwestern Iran, between the provinces of East Azerbaijan and Ardabil. Bozgoush ranges include of elevation of the Eocene volcanic and volcanoclastic rocks has been cut by monzonite and microdioritic dikes. The topographic elevations are between the northern and southern Bozgush faults and the faults will drift Bozgoush to the Sarab and Mianeh plains, in general show a Pop up structure. In this study, structural analysis and Neostress states of Bozgosh Mountains is used to tectonic study of the mountains. Evaluation of remote sensing data and structural identification using geological maps show various structures in the area such as faults (with a mechanism of thrust, normal and strike-slip), folds (anticline and syncline) and the basins and uplifts. Results of the stress inversion analysis and study of fault geometries and structures within Bozgoush, was used to determine of changes in the structural components during faulting and folding. In this research we find that the thrust faults have mainly NE-SW and E-W strike and 60 to 80-degree dip. Normal faults mainly have NW-SE direction and 60 to 70 degre dip. Also strike-slip faults have NNW-SSE direction and dip is near to vertical. Stress analysis result shown, the direction of compressional stress regime is NNE-SSW. In all studied area fold axis are parallel to the fault directions. Structural analysis and stress analysis results shown formation of this mountain chain compatible with the transpression tectonic model.Bozgoush Mountains located in northwestern Iran, between the provinces of East Azerbaijan and Ardabil. Bozgoush ranges include of elevation of the Eocene volcanic and volcanoclastic rocks has been cut by monzonite and microdioritic dikes. The topographic elevations are between the northern and southern Bozgush faults and the faults will drift Bozgoush to the Sarab and Mianeh plains, in general show a Pop up structure. In this study, structural analysis and Neostress states of Bozgosh Mountains is used to tectonic study of the mountains. Evaluation of remote sensing data and structural identification using geological maps show various structures in the area such as faults (with a mechanism of thrust, normal and strike-slip), folds (anticline and syncline) and the basins and uplifts. Results of the stress inversion analysis and study of fault geometries and structures within Bozgoush, was used to determine of changes in the structural components during faulting and folding. In this research we find that the thrust faults have mainly NE-SW and E-W strike and 60 to 80-degree dip. Normal faults mainly have NW-SE direction and 60 to 70 degre dip. Also strike-slip faults have NNW-SSE direction and dip is near to vertical. Stress analysis result shown, the direction of compressional stress regime is NNE-SSW. In all studied area fold axis are parallel to the fault directions. Structural analysis and stress analysis results shown formation of this mountain chain compatible with the transpression tectonic model.https://nfag.basu.ac.ir/article_5780_294a8ed24b1ad22ec2e7efea049b8737.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Geochemistry of mafic igneous rocks of Baghcheghaz region (northeast of Hamedan province): with emphasis on origin and tectonic environmentGeochemistry of mafic igneous rocks of Baghcheghaz region (northeast of Hamedan province): with emphasis on origin and tectonic environment117131573710.22084/nfag.2024.29351.1614FAS.AsadbeygiPh. D. student. Dept., of Geology, Faculty of Science, Bu Ali Sina University, Hamedan, IranH.ShahbaziAssoc. Prof., Dept., of Geology, Faculty of Science, Bu Ali Sina University, Hamedan, Iran0000-0003-3952-8104Journal Article20240515The Baghcheghaz intrusive mass is exposed in Hamadan province and in the northeast of Famenin city in the Sanandaj zone of Sirjan. Based on petrographic and geochemical studies, the type of rock that forms the mass is gabbro. The results of geochemical analysis show that these rocks are related to calcalkaline and tholeiite magmatic series. The trends formed in the Harker diagrams and their geochemical continuity, the patterns of the spider diagrams and the parallelism of the trends of these diagrams and the existence of enrichment in K and Pb elements and depletion in Nb confirm the common origin of the samples and indicate the involvement of magma with the continental crust. The nature and chemical composition of rocks in the region have undergone magmatic processes such as fractional crystallization, partial melting, and contamination.The pattern of changes of normalized rare earth elements compared to chondrite and primary mantle show that the values of rare earth elements LREE are higher than heavy earth elements HREE. The graphs related to the minor elements show that the magma forming the igneous rocks of the Baghcheghaz intrusive mass originates from the mantle with the composition of spinel lherzolite and with a low to medium partial melting degree (5% to about 30%) and in a subduction environment and volcanic arcs are formed on the active continental margin.The Baghcheghaz intrusive mass is exposed in Hamadan province and in the northeast of Famenin city in the Sanandaj zone of Sirjan. Based on petrographic and geochemical studies, the type of rock that forms the mass is gabbro. The results of geochemical analysis show that these rocks are related to calcalkaline and tholeiite magmatic series. The trends formed in the Harker diagrams and their geochemical continuity, the patterns of the spider diagrams and the parallelism of the trends of these diagrams and the existence of enrichment in K and Pb elements and depletion in Nb confirm the common origin of the samples and indicate the involvement of magma with the continental crust. The nature and chemical composition of rocks in the region have undergone magmatic processes such as fractional crystallization, partial melting, and contamination.The pattern of changes of normalized rare earth elements compared to chondrite and primary mantle show that the values of rare earth elements LREE are higher than heavy earth elements HREE. The graphs related to the minor elements show that the magma forming the igneous rocks of the Baghcheghaz intrusive mass originates from the mantle with the composition of spinel lherzolite and with a low to medium partial melting degree (5% to about 30%) and in a subduction environment and volcanic arcs are formed on the active continental margin.https://nfag.basu.ac.ir/article_5737_e6e9099e59636a015536fbb07f979201.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Biostratigraphy the Surgah Formation in the Khorramabad anticline ( High Zagros zone )Biostratigraphy the Surgah Formation in the Khorramabad anticline ( High Zagros zone )132142576310.22084/nfag.2024.29206.1611FAI.Maghfouri MoghaddamAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranGh.DarabiPh. D. (graduated), Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranZ.Rahimi Rok RokM. Sc. (graduated), Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranM.SedaghatniaPh. D. (graduated), Expert of the Central Laboratory of Lorestan University, Khorramabad, IranJournal Article20240412The Surgah Formation is a deep marine sedimentary sequence that extends only in the Lorestan zone and its margins. In order to study the stratigraphic and biostratigraphic characterises of this formation, the Falakolddin section in the High Zagros zone, adjacent to the northern part of the Lorestan zone, was selected. The thickness of the Surgah formation in this section is 80.80 meters and includes dark gray medium to thick argillaceous limestones and limestones, which has more clay content compared to other outcrops of the Surgah Formation. In the biostratigraphic studies of this formation, 18 species of 7 genera of planktonic foraminifera were identified, based on their distribution, four biological zones were introduced, which are: Helvetoglobotruncana helvetica total renge zone, Marginotruncanasigali-Dicarinella primitiva partial range zone, Dicarinella concavata interval zone and Dicarinella asymetrica total range zone . Based on the introduced biozones , the age of Surgah Formation in this section has been determined Middle Turonian -Late SantonianThe Surgah Formation is a deep marine sedimentary sequence that extends only in the Lorestan zone and its margins. In order to study the stratigraphic and biostratigraphic characterises of this formation, the Falakolddin section in the High Zagros zone, adjacent to the northern part of the Lorestan zone, was selected. The thickness of the Surgah formation in this section is 80.80 meters and includes dark gray medium to thick argillaceous limestones and limestones, which has more clay content compared to other outcrops of the Surgah Formation. In the biostratigraphic studies of this formation, 18 species of 7 genera of planktonic foraminifera were identified, based on their distribution, four biological zones were introduced, which are: Helvetoglobotruncana helvetica total renge zone, Marginotruncanasigali-Dicarinella primitiva partial range zone, Dicarinella concavata interval zone and Dicarinella asymetrica total range zone . Based on the introduced biozones , the age of Surgah Formation in this section has been determined Middle Turonian -Late Santonianhttps://nfag.basu.ac.ir/article_5763_1819020b02e926785cf3be594d957696.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Investigations on the Silvana region gabbro, south of Urmia, pressure-temperature-fluid conditions based on the crystal chemistryInvestigations on the Silvana region gabbro, south of Urmia, pressure-temperature-fluid conditions based on the crystal chemistry143158576410.22084/nfag.2024.29637.1622FAM.ModjarradAssoc. Prof., Dept., of Geology, Faculty of Science, Urmia University, Urmia, IranJournal Article20240721In this manuscript, we focused on the Silvana ophiolite-related gabbro, south of Urmia. The essential aim is studying constituent minerals classification and understanding formation conditions of this rock type based on the mineral chemistry. The mentioned gabbro was intruded in the serpentinized ultramafic unit in the area and outcropped along the Asbi Bunar fault as colored mélange accompanied by other ophiolitic members. Abundant rock types are gabbro and hornblende gabbro with clinopyroxene, amphibole, plagioclase, and ore minerals as major minerals. Additionally, some biotite, calcite and apatite as minor or accessory phases exist. Clinopyroxenes composition in these rocks is diopsidic, amphiboles are parasitic-kaersutite, plagioclases are anorthite-rich, opaque minerals are ilmenite and biotites are phlogopitic, based on the EPMA analyses. Mineral chemistry of both amphibole and clinopyroxene in the studied gabbro, shows a supra subduction zone/fore-arc setting for them. Also, the oxygen/water fugacity of the parent magma was high. The crystallization temperature of 800-1000 ⁰C at the 5-8 kbar pressure using amphibole composition and 1150 ⁰C at low pressure by clinopyroxene are evaluated.In this manuscript, we focused on the Silvana ophiolite-related gabbro, south of Urmia. The essential aim is studying constituent minerals classification and understanding formation conditions of this rock type based on the mineral chemistry. The mentioned gabbro was intruded in the serpentinized ultramafic unit in the area and outcropped along the Asbi Bunar fault as colored mélange accompanied by other ophiolitic members. Abundant rock types are gabbro and hornblende gabbro with clinopyroxene, amphibole, plagioclase, and ore minerals as major minerals. Additionally, some biotite, calcite and apatite as minor or accessory phases exist. Clinopyroxenes composition in these rocks is diopsidic, amphiboles are parasitic-kaersutite, plagioclases are anorthite-rich, opaque minerals are ilmenite and biotites are phlogopitic, based on the EPMA analyses. Mineral chemistry of both amphibole and clinopyroxene in the studied gabbro, shows a supra subduction zone/fore-arc setting for them. Also, the oxygen/water fugacity of the parent magma was high. The crystallization temperature of 800-1000 ⁰C at the 5-8 kbar pressure using amphibole composition and 1150 ⁰C at low pressure by clinopyroxene are evaluated.https://nfag.basu.ac.ir/article_5764_9715d04413f296eaf3c30c47cec3daa6.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Evaluation of the acid mine drainage potential from the spoils of the Tazare Coal Mine, NE IranEvaluation of the acid mine drainage potential from the spoils of the Tazare Coal Mine, NE Iran159176578410.22084/nfag.2024.29747.1627FAE.RabieeM. Sc. student of Geology, Faculty of Earth Sciences, Shahrood University of Technology, Shahrood, IranG.Forghani TehraniAssist. Prof., Dept., of Geology, Faculty of Earth Sciences, Shahrood University of Technology, Shahrood, IranS.Zarei DoudejiAssoc. Prof., Dept., of Geology, Faculty of Earth Sciences, Shahrood University of Technology, Shahrood, IranJournal Article20240909The Tazare Coal Mine is located in the Eastern Alborz structural zone, NE Iran. The present study aims to investigate the mineralogical and geochemical characteristics of spoils produced in Tazareh coal mine, and to evaluate the potential of the waste materials to produce acid mine drainage as a result of oxidation processes. For these purposes, 8 representative spoil samples were collected, and the mineralogy, geochemistry, and static geochemical tests were carried out. Mineralogical studies indicate the presence of pyrite, chalcopyrite, arsenopyrite, chalcocite, marcasite, albite, kaolinite and quartz in the studied samples. Pyrite presented as angular, spherical fragments and framboidal aggregates, or as filling the fissure. The studied samples were not enriched in Mn and Fe, whereas they were significantly enriched in Ni, Cr, Cu, Pb, highly enriched in As and Zn. The highest concentration of elements was recorded in sample no. 6. On the basis of the results of static tests of acid mine drainage prediction, the pH of saturated paste was higher than 4 and the electrical conductivity of saturated paste of 6 samples was higher than 2000 µs/cm. According to static test results, the studied samples, especially samples no. 3 and 6, were of acid producing potential. This conclusion was confirmed by field observations. The obtained results in this study show the necessity of tackling the environmental management measures in the Tazare Coal Mine district.The Tazare Coal Mine is located in the Eastern Alborz structural zone, NE Iran. The present study aims to investigate the mineralogical and geochemical characteristics of spoils produced in Tazareh coal mine, and to evaluate the potential of the waste materials to produce acid mine drainage as a result of oxidation processes. For these purposes, 8 representative spoil samples were collected, and the mineralogy, geochemistry, and static geochemical tests were carried out. Mineralogical studies indicate the presence of pyrite, chalcopyrite, arsenopyrite, chalcocite, marcasite, albite, kaolinite and quartz in the studied samples. Pyrite presented as angular, spherical fragments and framboidal aggregates, or as filling the fissure. The studied samples were not enriched in Mn and Fe, whereas they were significantly enriched in Ni, Cr, Cu, Pb, highly enriched in As and Zn. The highest concentration of elements was recorded in sample no. 6. On the basis of the results of static tests of acid mine drainage prediction, the pH of saturated paste was higher than 4 and the electrical conductivity of saturated paste of 6 samples was higher than 2000 µs/cm. According to static test results, the studied samples, especially samples no. 3 and 6, were of acid producing potential. This conclusion was confirmed by field observations. The obtained results in this study show the necessity of tackling the environmental management measures in the Tazare Coal Mine district.https://nfag.basu.ac.ir/article_5784_6157966f9b9e2f35d2266675bad8b7f8.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Petrography and dolomitization model of Shahbazan Formation (Anticline Khorramabad, north of Lorestan)Petrography and dolomitization model of Shahbazan Formation (Anticline Khorramabad, north of Lorestan)177200580710.22084/nfag.2024.30078.1644FAN.Maleki SadeghiPh. D. (graduated), Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranR.Zarei SahamiehAssoc. Prof., Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, IranJournal Article20240729The studied area is located in the north of Lorestan and 25 km north of Khorram Abad city. In this area, the Shahbazan Formation with the dominant lithology of limestone and dolomite is 85 meters thick, its lower boundary is a slope on the Kashkan detrial formation and its upper boundary is continuous with the carbonates of the Asmari formation. The facade is covered. Based on petrographic and geochemical studies, two groups of dolomites were identified. Primary dolomites (delomicrites) with a mosaic and often amorphous texture in sizes less than 10 microns and secondary dolomites (dolomicrosparites and doloasparites) with a semi-shaped to shaped texture They were observed in sizes larger than 10 microns and even larger than 250 microns.In the studied dolomites, there is an increasing trend of Fe and Mn elements and a decreasing trend of Sr element from dolomicrites towards dolomicrosparites and dolosparites. The presence of some evidence such as bird's eye porosity, algal laminae and intraclasts and the absence of evaporite minerals in the studied samples showed that the primary dolomites were formed in a tidal model and then As a result of seepage of basin floor sediments in the carbonate platform of Shahbazan Formation, secondary dolomites have expanded in a shallow to medium burial diagenesis model.The relatively high concentration of Na in the studied dolomites (0.1 to 1.4% by weight) indicates the influence of basin floor sediments on them. The ratio of Ca/Mg in all the studied dolomites is higher than the standard limit (1.6) and indicates that they are non-stoichiometric. This issue can be justified considering the age of Shahbazan formation in this part of Lorestan sedimentary basin.The studied area is located in the north of Lorestan and 25 km north of Khorram Abad city. In this area, the Shahbazan Formation with the dominant lithology of limestone and dolomite is 85 meters thick, its lower boundary is a slope on the Kashkan detrial formation and its upper boundary is continuous with the carbonates of the Asmari formation. The facade is covered. Based on petrographic and geochemical studies, two groups of dolomites were identified. Primary dolomites (delomicrites) with a mosaic and often amorphous texture in sizes less than 10 microns and secondary dolomites (dolomicrosparites and doloasparites) with a semi-shaped to shaped texture They were observed in sizes larger than 10 microns and even larger than 250 microns.In the studied dolomites, there is an increasing trend of Fe and Mn elements and a decreasing trend of Sr element from dolomicrites towards dolomicrosparites and dolosparites. The presence of some evidence such as bird's eye porosity, algal laminae and intraclasts and the absence of evaporite minerals in the studied samples showed that the primary dolomites were formed in a tidal model and then As a result of seepage of basin floor sediments in the carbonate platform of Shahbazan Formation, secondary dolomites have expanded in a shallow to medium burial diagenesis model.The relatively high concentration of Na in the studied dolomites (0.1 to 1.4% by weight) indicates the influence of basin floor sediments on them. The ratio of Ca/Mg in all the studied dolomites is higher than the standard limit (1.6) and indicates that they are non-stoichiometric. This issue can be justified considering the age of Shahbazan formation in this part of Lorestan sedimentary basin.https://nfag.basu.ac.ir/article_5807_681a23b0649e61ca572cb5bb8db206ec.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Combining methods of analysis of main components in Remote Sensing and Geochemistry of the geological map of one hundred thousand localities using a new weighing cell method to identify gold anomaliesCombining methods of analysis of main components in Remote Sensing and Geochemistry of the geological map of one hundred thousand localities using a new weighing cell method to identify gold anomalies201215582610.22084/nfag.2024.30000.1640FAA. R.PayamaniPh. D. student, of Mining Engineering, Mahallat branch, Islamic Azad University, Mahallat, IranS.DehghanAssist. Prof., Dept., of Mining, Mahallat branch, Islamic Azad University, Mahallat, IranB.BabaeiAssist. Prof., Dept., of Mining, Mahallat branch, Islamic Azad University, Mahallat, IranH.Asadi HarouniAssist. Prof., Dept., of Mining Engineering, Isfahan University of Technology, Isfahan, IranJournal Article20241016Modeling mineral potential and identifying promising areas is one of the most important stages of preliminary exploration. Examining and understanding different and new modeling methods are important because of increasing the probability of discovery and reducing risk. The studied area in terms of structural divisions of the geological zones of Iran, includes parts of the volcanic belt and the metallogenic state of Sanandaj-Sirjan. According to the subduction and closure of the Neotethys ocean of the Sanandaj-Sirjan metamorphic belt due to the intrusion of mostly acidic calc-alkaline intrusive masses with the composition of mostly granite to granodiorite and quartz monzonite in older sedimentary and sometimes volcanic units, scattered mineralizations in this has created a zone. By using the data received from the Aster sensor, PCA method was used as an efficient and optimal method to detect the changes in the area. In the geochemistry, by analyzing the geochemical data, it was determined that Au, Cu, AS and Ag elements with a skewness above eight and a maximum value equal to several tens to several hundred times the global background value of these elements have a relative mineralization potential in this range. Among them, gold has an anomalous community. In the geochemical factor analysis, it was observed that in the first component, the highest factor load is for the elements Nb, La, Ce, Li, P, W, Fe, and then the Au element has a high factor load. This factor alone justifies about 25% of the total variability due to the multiplicity of the mentioned elements. After the preparation of remote sensing and geochemistry information layers, information integration was done using the new cellular weighting method and due to the presence of mines in areas with an overlap of 51%, the anomalies obtained with the mines of the region were identified.Modeling mineral potential and identifying promising areas is one of the most important stages of preliminary exploration. Examining and understanding different and new modeling methods are important because of increasing the probability of discovery and reducing risk. The studied area in terms of structural divisions of the geological zones of Iran, includes parts of the volcanic belt and the metallogenic state of Sanandaj-Sirjan. According to the subduction and closure of the Neotethys ocean of the Sanandaj-Sirjan metamorphic belt due to the intrusion of mostly acidic calc-alkaline intrusive masses with the composition of mostly granite to granodiorite and quartz monzonite in older sedimentary and sometimes volcanic units, scattered mineralizations in this has created a zone. By using the data received from the Aster sensor, PCA method was used as an efficient and optimal method to detect the changes in the area. In the geochemistry, by analyzing the geochemical data, it was determined that Au, Cu, AS and Ag elements with a skewness above eight and a maximum value equal to several tens to several hundred times the global background value of these elements have a relative mineralization potential in this range. Among them, gold has an anomalous community. In the geochemical factor analysis, it was observed that in the first component, the highest factor load is for the elements Nb, La, Ce, Li, P, W, Fe, and then the Au element has a high factor load. This factor alone justifies about 25% of the total variability due to the multiplicity of the mentioned elements. After the preparation of remote sensing and geochemistry information layers, information integration was done using the new cellular weighting method and due to the presence of mines in areas with an overlap of 51%, the anomalies obtained with the mines of the region were identified.https://nfag.basu.ac.ir/article_5826_99f42c473afe0eb4bd047ae133b851fc.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Mineral chemistry and geothermobarometry of pyroxenes in East Harzburgites of Hajiabad (Hormozgan province): Implication to petrogenetic evolution and tectonomagmatic settingMineral chemistry and geothermobarometry of pyroxenes in East Harzburgites of Hajiabad (Hormozgan province): Implication to petrogenetic evolution and tectonomagmatic setting216233586010.22084/nfag.2024.29783.1629FAH.FalahiPh. D. student, Dept., of Geology, Faculty of Natural Sciences, University of Tabriz, Tabriz, IranS.SedighianAssist. Prof., Dept., of Geology, Faculty of Sciences, Velayat University, Iranshahr, Sistan and Bluchestan, Iran0009-0004-4674-8329R.AkbarpourM. Sc. (graduated), Dept., of Geology, Islamic Azad University of Zarand, Kerman, IranJournal Article20240820Mantle peridotites form an important part of Esfandah-Hajiabad ophiolitic belt on the southeast of Sanandaj-Sirjan zone. The East Harzburgites of Hajiabad, having minerals such as olivine, orthopyroxene, and clinopyroxene, are the main unit among this set of ultramafic rocks that do not have obvious layering and are observed as masses. The orientation of minerals, recrystallization and different generations of minerals indicate that these rocks are prouduced in the upper mantle and implacement in the crustal environment. Mineral chemistry of pyroxene in harzburgites show that in these rocks, orthopyroxenes are located in the enstatite range and clinopyroxenes are located in the diopside range. Based on thermometric and barometric studies on pyroxene crystals in harzburgites, the equilibrium temperature is around 1342.11 ͦ C and the crystallization pressure is around 14.12 kb, which corresponds to the range of spinel peridotite. Based on geochemical and tectonic studies, the harzburgites in the east of Hajiabad were formed in the range of abyssal peridotites towards a supersubduction zone, probably similar to back-arc basin with about 12% partialmelting. The behavior of rare earth elements associated with the rock samples of the study area also proves the partialmelting and metasomatism processes that occurred during the formation of these rocks.Mantle peridotites form an important part of Esfandah-Hajiabad ophiolitic belt on the southeast of Sanandaj-Sirjan zone. The East Harzburgites of Hajiabad, having minerals such as olivine, orthopyroxene, and clinopyroxene, are the main unit among this set of ultramafic rocks that do not have obvious layering and are observed as masses. The orientation of minerals, recrystallization and different generations of minerals indicate that these rocks are prouduced in the upper mantle and implacement in the crustal environment. Mineral chemistry of pyroxene in harzburgites show that in these rocks, orthopyroxenes are located in the enstatite range and clinopyroxenes are located in the diopside range. Based on thermometric and barometric studies on pyroxene crystals in harzburgites, the equilibrium temperature is around 1342.11 ͦ C and the crystallization pressure is around 14.12 kb, which corresponds to the range of spinel peridotite. Based on geochemical and tectonic studies, the harzburgites in the east of Hajiabad were formed in the range of abyssal peridotites towards a supersubduction zone, probably similar to back-arc basin with about 12% partialmelting. The behavior of rare earth elements associated with the rock samples of the study area also proves the partialmelting and metasomatism processes that occurred during the formation of these rocks.https://nfag.basu.ac.ir/article_5860_32508f53f24c46f685870a075eaaa29c.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Petrology of Chenask intrusive rocks in the eastern Qazvin, central Alborz: An explanation for Eocene magmatism in an extensional basin related to syn-collisional settingPetrology of Chenask intrusive rocks in the eastern Qazvin, central Alborz: An explanation for Eocene magmatism in an extensional basin related to syn-collisional setting234252587010.22084/nfag.2024.29946.1638FAF.SepidbarAssist. Prof., Dept., of Geology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, IranB.Borouzi NiyatPh. D. student, Dept., of Geology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, IranJournal Article20241002The Chenasak intrusives are located in eastern Qazvin, western end of the central Alborz. These intrusives consist of granular-textured intermediate menzonite and syenite rocks with mineralogy mainly consisting of plagioclase, potassium feldspar, amphibole, and biotite with varying volume percentages. U-Pb zircon dating data indicate that the menzonite and syenite have approximately the same ages of 41.8±0.5 and 41.2±0.6 Ma, respectively. These rocks have high-potassium calc-alkaline to shoshonite geochemical characteristics and are enriched in large ionic radius elements (LILE) and light rare earth elements (LREE) and depleted in high field strength elements (HFSE) and heavy rare earth elements (HREE), indicating magmas formed in the subduction zone. Whole-rock Nd-Sr isotope ratios indicate that the ɛNd and 87Sr/86Sr values of these rocks vary from +0.5 to +1.2 and 0.70483 to 0.70648. Whole-rock chemistry and isotopic data indicate that the magma forming the menzonite and syenite was formed by the crystalline fractionation of the primary melt derived from the metasomatized mantle in a tensile basin formed by the rollback of the subducting plate during the collision of the Iran and Arabia plates.The Chenasak intrusives are located in eastern Qazvin, western end of the central Alborz. These intrusives consist of granular-textured intermediate menzonite and syenite rocks with mineralogy mainly consisting of plagioclase, potassium feldspar, amphibole, and biotite with varying volume percentages. U-Pb zircon dating data indicate that the menzonite and syenite have approximately the same ages of 41.8±0.5 and 41.2±0.6 Ma, respectively. These rocks have high-potassium calc-alkaline to shoshonite geochemical characteristics and are enriched in large ionic radius elements (LILE) and light rare earth elements (LREE) and depleted in high field strength elements (HFSE) and heavy rare earth elements (HREE), indicating magmas formed in the subduction zone. Whole-rock Nd-Sr isotope ratios indicate that the ɛNd and 87Sr/86Sr values of these rocks vary from +0.5 to +1.2 and 0.70483 to 0.70648. Whole-rock chemistry and isotopic data indicate that the magma forming the menzonite and syenite was formed by the crystalline fractionation of the primary melt derived from the metasomatized mantle in a tensile basin formed by the rollback of the subducting plate during the collision of the Iran and Arabia plates.https://nfag.basu.ac.ir/article_5870_1f74a54f39b3123ad272ca0a06e7463f.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Paleoecology of Upper Eocene-Chattian deposits (Pabdeh and Asmari formations) in Maron oil fieldPaleoecology of Upper Eocene-Chattian deposits (Pabdeh and Asmari formations) in Maron oil field253277510710.22084/nfag.2023.27329.1543FAM.GoodarziPh. D. student. Dept., of Geology, Faculty of Science, Lorestan University, Khorramabad, Iran0000-0002-6415-2981H.AmiribakhtiarPh. D. of Geology, National Iranian South Oil Company (NISOC), Ahwaz, IranM. R.NuraeinezhadPh. D. student., Dept., of Sedimentary Basins and Petroleum, Faculty of Earth Sciences, Shahid Beheshti University, Tehran, IranM.SedaghatniaPh. D. (graduated), Expert of the Central Laboratory of Lorestan University, Khorramabad, IranJournal Article20250528In the Current research paleoecology of the Upper Eocene (Pabdeh Formation) and Chattian (Asmari Formation) has been studied by analyzing 250 thin sections in the Maron oil field (A and B). in the studied wells the light conditions vary from the dark to maximum (aphotic to euphotic), salinity from the normal to slightly higher than normal (34- 40 Psu), and the nutrients fluctuate from oligotrophic to eutrophic. In the Upper Eocene interval (Pabdeh Formation) the abundance of Planktonic foraminifera indicate a quiet, low energy and deep marine setting and in the Oligocene the occurrence of larger benthic foraminifera in the basal parts of the Asmari Formation (distal part of the middle ramp) point to low hydrodynamic energy conditions and a stable substrate. The presences of hyaline foraminifera with lenticular, thicker tests and smaller in size in the proximal parts of the middle ramp suggest higher energy and light levels and a higher energy shallow marine environment with unstable and firmground substrate.In the Current research paleoecology of the Upper Eocene (Pabdeh Formation) and Chattian (Asmari Formation) has been studied by analyzing 250 thin sections in the Maron oil field (A and B). in the studied wells the light conditions vary from the dark to maximum (aphotic to euphotic), salinity from the normal to slightly higher than normal (34- 40 Psu), and the nutrients fluctuate from oligotrophic to eutrophic. In the Upper Eocene interval (Pabdeh Formation) the abundance of Planktonic foraminifera indicate a quiet, low energy and deep marine setting and in the Oligocene the occurrence of larger benthic foraminifera in the basal parts of the Asmari Formation (distal part of the middle ramp) point to low hydrodynamic energy conditions and a stable substrate. The presences of hyaline foraminifera with lenticular, thicker tests and smaller in size in the proximal parts of the middle ramp suggest higher energy and light levels and a higher energy shallow marine environment with unstable and firmground substrate.https://nfag.basu.ac.ir/article_5107_9f93557d309f655ff06f109a08dcf7c4.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251222Thermobarometry Chelvan igneous rocks using amphibole, biotite, plagioclase, pyroxene minerals, north of Shahrekord, Sanandaj-Sirjan zone.Thermobarometry Chelvan igneous rocks using amphibole, biotite, plagioclase, pyroxene minerals, north of Shahrekord, Sanandaj-Sirjan zone.278292617510.22084/nfag.2025.31268.1683FAM.AhankoubAssist. Prof., Dept., of Geology, Payame Noor University, Tehran, Iran0000-0002-9941-7927Journal Article20250514Abstract: The area is in 45 kilometers north of Shahrekord and near the city of Chelvan in the middle part of the Sanandaj-Sirjan structural zone. The stratigraphic column of the area consists of: Cretaceous carbonates, Jurassic shales and sandstones, and volcanic rocks. The petrographic observation of volcanic rocks indicate the presence of igneous rocks of the andesite, andesite-basalt and basalt types with the main minerals olivine, pyroxene, plagioclase and amphibole, along with biotite and minor and opaque minerals that have a dominant microlitic porphyry and porphyry texture. The results of the chemical analysis of pyroxene phenocrysts indicate the presence of augite-type pyroxenes with a chemical composition spectrum of Fs 12.52-17.38 En 42.71-Wo 36.92-39.67, which were formed in the temperature range of 1200 to 1300 degrees Celsius and a pressure range of 6 to 10 kilobars. The amphiboles are magnesian-hornblende type that crystallized at a pressure of 2.7 to 5 kilobars and a temperature of 720 to 800 degrees Celsius. The micas of this area are primary magmatic magnesian biotites that were formed at a temperature of 580 to 680 degrees Celsius, and the composition of plagioclases fluctuates from oligoclase to labradorite, indicating the crystallization temperature 700-800 degrees Celsius. The combination of mineral chemical analysis data of the Chelwan igneous rocks indicates the tectonic setting of calc-alkaline magmas that formed in a subduction zone.Abstract: The area is in 45 kilometers north of Shahrekord and near the city of Chelvan in the middle part of the Sanandaj-Sirjan structural zone. The stratigraphic column of the area consists of: Cretaceous carbonates, Jurassic shales and sandstones, and volcanic rocks. The petrographic observation of volcanic rocks indicate the presence of igneous rocks of the andesite, andesite-basalt and basalt types with the main minerals olivine, pyroxene, plagioclase and amphibole, along with biotite and minor and opaque minerals that have a dominant microlitic porphyry and porphyry texture. The results of the chemical analysis of pyroxene phenocrysts indicate the presence of augite-type pyroxenes with a chemical composition spectrum of Fs 12.52-17.38 En 42.71-Wo 36.92-39.67, which were formed in the temperature range of 1200 to 1300 degrees Celsius and a pressure range of 6 to 10 kilobars. The amphiboles are magnesian-hornblende type that crystallized at a pressure of 2.7 to 5 kilobars and a temperature of 720 to 800 degrees Celsius. The micas of this area are primary magmatic magnesian biotites that were formed at a temperature of 580 to 680 degrees Celsius, and the composition of plagioclases fluctuates from oligoclase to labradorite, indicating the crystallization temperature 700-800 degrees Celsius. The combination of mineral chemical analysis data of the Chelwan igneous rocks indicates the tectonic setting of calc-alkaline magmas that formed in a subduction zone.https://nfag.basu.ac.ir/article_6175_c80d9ba4852b67046bee487bcd9802c0.pdfBu-Ali Sina UniversityNew Findings in
Applied Geology2228-5873193820251122Epitaxial growth mechanism of the Au-bearing arsenian pyrites in Yeganli-2 gold deposit, north of Takab: New insight from complex interaction of crystal growth kinetics and gold concentrationEpitaxial growth mechanism of the Au-bearing arsenian pyrites in Yeganli-2 gold deposit, north of Takab: New insight from complex interaction of crystal growth kinetics and gold concentration293308624910.22084/nfag.2025.31449.1690FAE.Tale FazelAssoc. Prof., Dept., of Geology, Faculty of Science, Bu Ali Sina University, Hamedan, Iran0000-0002-8776-1405Journal Article20250618Understanding the complex interplay between the crystallization processes and distribution of precious trace elements (e.g., gold) is of great importance in economic geology. In this contribution, the effective factors on the incorporation of trace elements, especially gold, during the epitaxial growth of Au-bearing arsenian pyrite crystal in the Yeganli gold deposit (north of Takab) have been interpreted by advanced electron-atomic techniques. According to SEM evidence, As-rich (> 3 ppm) bright bands with a thickness of 10 nm have other trace elements (e.g., Cu, Sb, Pb, and Tl). According to the evidence of APT, the heterogeneous distribution of trace elements with the appearance of islands along the discontinuous planar features from the outer edge of the As-rich bright bands is known as Stranski-Krastanov growth mode, and with the distance from these bands, epitaxial growth occurs as a result of periodic fluid fluctuations. Also, As-induced lattice distortion facilitates surface adsorption of dopant trace metals, which leads to “unstructured” impurities clustering locally in crystal defects. In summary, based on nano-scale textural-chemical evidence from arsenitepyrite crystals, it can be said that the kinetics of crystal growth and its complex interaction with the equilibrating hydrothermal fluid play an important role in the distribution and concentration of gold, which can be considered as a prospecting implication at the mineralogical scale.Understanding the complex interplay between the crystallization processes and distribution of precious trace elements (e.g., gold) is of great importance in economic geology. In this contribution, the effective factors on the incorporation of trace elements, especially gold, during the epitaxial growth of Au-bearing arsenian pyrite crystal in the Yeganli gold deposit (north of Takab) have been interpreted by advanced electron-atomic techniques. According to SEM evidence, As-rich (> 3 ppm) bright bands with a thickness of 10 nm have other trace elements (e.g., Cu, Sb, Pb, and Tl). According to the evidence of APT, the heterogeneous distribution of trace elements with the appearance of islands along the discontinuous planar features from the outer edge of the As-rich bright bands is known as Stranski-Krastanov growth mode, and with the distance from these bands, epitaxial growth occurs as a result of periodic fluid fluctuations. Also, As-induced lattice distortion facilitates surface adsorption of dopant trace metals, which leads to “unstructured” impurities clustering locally in crystal defects. In summary, based on nano-scale textural-chemical evidence from arsenitepyrite crystals, it can be said that the kinetics of crystal growth and its complex interaction with the equilibrating hydrothermal fluid play an important role in the distribution and concentration of gold, which can be considered as a prospecting implication at the mineralogical scale.https://nfag.basu.ac.ir/article_6249_bcb7c13ff9746a60fa8c3e748acd054d.pdf