List of Articles
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Open Access Article
1 - Biostratigraphy of Mesozoic-Cenozoic boundary based on calcareous nannofossils in Bulfars section, Southwest Iran
Saeedeh SenemariTo study Mesozoic –Cenozoic boundary based on calcareous nannofossils, section of Tang-e- Bulfars in East Ramhormoz was studied. The fossil groups in determining the relative age of the Mesozoic and Cenozoic layers are important. In this interval, a thickness of 32 m MoreTo study Mesozoic –Cenozoic boundary based on calcareous nannofossils, section of Tang-e- Bulfars in East Ramhormoz was studied. The fossil groups in determining the relative age of the Mesozoic and Cenozoic layers are important. In this interval, a thickness of 32 meters of shale and limestone were studied and for the first time 35 species of nannofossils were identified. As a result, the identified biozones includes Reinhardtites Levis Zone (UC18/CC24) and the base of Arkhangelskiella cymbiformis (CC25/UC19) with Late Cretaceous age and Heliolithus kleinpellii Zone (NP6) with Selandian/Thanetian age. Based on the identified zones, the transition period of Early Maastrichtian-Selandian/Thanetian and the boundary between the Cretaceous to Paleogene was determined as a discontinuity. The presence of index species of calcareous nannofossils indicates that the studied sediments in the section of Tang-e- Bulfars were deposited in the lower latitudes and under warm climatic conditions. . Manuscript profile -
Open Access Article
2 - Cenozoic superposed deformation in the south of Central Iran: Implication for folding and tectonic stress field in Rafsanjan structural belt
لیلا عبادی Seyd Ahmad Alavi Mohamad Reaz GhasemiThe South Central Iran Block has experienced polyphase intensive deformation in the Cenozoic time. Large-scale superposed folds in South Rafsanjan document the Cenozoic tectonic events within the South Central Iran Block. In this study, a case study of this deformation MoreThe South Central Iran Block has experienced polyphase intensive deformation in the Cenozoic time. Large-scale superposed folds in South Rafsanjan document the Cenozoic tectonic events within the South Central Iran Block. In this study, a case study of this deformation inferred from regional-scale Rafsanjan superposed folds in the south of Central Iran is presented to reconstruct the deformation sequence and tectonic regime during crustal shortening. These data indicate that the superposed folds, dominated by a two-stage tectonic transpression regime which experienced two phases of superposed folding, leading to the orthogonal superposition of WNW–ESE-trending folds onto NE–SW trending folds. Structural analyses and fault kinematic analyses in the Rafsanjan Structural Belt indicate a two-stage syn-folding paleo-stress field during the Cenozoic. The early phase of tectonism is characterized by late Miocene NW-SE transpression, which led to the development of NE-trending fold structures and causing the occurrence of an orogeny perpendicular shortening. This tectonic event was most likely associated with progressive anticlockwise rotation of the Central Iran Block. Subsequent tectonic event from Late Miocene until Quaternary contributed to a phase of contraction that overprinted the early NNE–SSW shortening in the interior parts of the studied area and generated a large-scale NE-convex fold belt and the typical large-scale superposed folds within the South of Central Iran Block. In terms of geodynamics, the later tectonism is likely to have been related to the NE-directed convergence between the Arabian and the Eurasian Plates. Manuscript profile -
Open Access Article
3 - Petrogensis and tectonomagmatic setting of Moghanlu Granitoid (NW of Iran)
Fatemeh Najmi Leili Fathiyan Seyed Ahmad Mazaheri Farhad Aliani Saeid Saadat Ali Akbar Baharifar Azam Entezari Mohamad Hossian ZarinkoubThe Moghanlu granitoid was located in the northwest of central Iranian structural zone with a Precamberian age. Based on field observations and microscopic studies, this body includes tonalite, monzogranite and granodiorite. Based on geochemical studies, tonalites are I MoreThe Moghanlu granitoid was located in the northwest of central Iranian structural zone with a Precamberian age. Based on field observations and microscopic studies, this body includes tonalite, monzogranite and granodiorite. Based on geochemical studies, tonalites are I-type, calc-alkaline, and weakly peraluminous. Based on isotopic studies [(87Sr/86Sr (i) and εNd (i) values equal to 0.710544, -7.01 respectively)], low values of La/Yb, Sr/Y , Nb/Ta, Ni and Cr, low fractionated patterns (flat pattern) of rare earth elements (REE) and negative anomaly of Eu, it can be concluded that they were resulted from melting of amphibolitic thickened mafic crust or under plate basalts (in the stability field of plagioclase) in low pressures and low depth in volcanic arc granitic area. Monzogranites are S-type, peraluminous and calc-alkaline, which are plotted in collision zone. These rocks are enriched in LILE and LREE and also depleted in HFSE, which represent negative anomaly of Ba, Ti, Nb, Sr with Mg number about 11-20. On the basis of this result, it can be concluded that the granitoids were generated from melting of crustal rocks (melt derived from pelitic rocks with high plagioclase content). Granodiorite are I-type, calc-alkaline and peraluminous. They have 87Sr/86Sr (i) and εNd(i) values of 0.71713, -10.55, Mg number between 31-33, negative anomaly of Sr and Nb, and also positive anomaly of La and Th, which represent that these rocks were generated from partial melting of lower to middle crust. These granodiorites were formed because of thickening and shorting due to continental- continental collision (collision of Iranian-Arabian plates). With respect to geographical location of Moghanlu body and the age of this units, it seems that these granitoide rocks formed on active continental margin during convergence of Central Iran and Alborz-Azarbayjan plates to Arabian platform during Precambrian. Manuscript profile -
Open Access Article
4 - Tectonomagmatic setting of the Eocene volcanic rocks in Ahovan area (Semnan)
Maryam Alipour Morteza Khalatbari-Jafari Mohsen Pourkermani Sedigheh Etesami Ali SorbiPetrology and tectonomagmatic setting of the Eocene volcanic rocks exposed in the Ahovan area, east of Semnan are presented and discussed. The studied rocks include basic-intermediate and acidic volcanic lavas and dikes, accompanied by intercalations of nummulite-bearin MorePetrology and tectonomagmatic setting of the Eocene volcanic rocks exposed in the Ahovan area, east of Semnan are presented and discussed. The studied rocks include basic-intermediate and acidic volcanic lavas and dikes, accompanied by intercalations of nummulite-bearing limestone, shallow water deposits, hyaloclastite and hyaloclastic breccia. The basic-intermediate lavas are exposed at the base and the rhyolitic and andesitic lavas are exposed at the top of the volcanic series, all of which may be attributed to a bimodal volcanism. It seems that Eocene volcanic activity occurred in shallow water to subaerial environments. Based on petrographical investigations, the volcanic lavas show basaltic, basaltic andesitic, andesitic, dacitic, rhyolitic and acidic tuffs compositions. The lavas have phyric to aphyric textures. The phyric lavas include plagioclase, augite and hornblend phenocrysts. They show microlitic, microcrystalline and intergranular groundmass in dikes. Disrupted zoning and sieve texture in plagioclase phenocrysts and heterogeneous groundmass might be interpreted by magma mixing. Study of the geochemical analyses, indicates high-k calc-alkaline to shoshonitic magmatic trends in the Ahovan area. Trace and REE spider diagrams, normalized with standard values, display enrichment of LILE and clear depletion of Nb and Ti. In tectonomagmatic diagrams, these samples plot in the arc field which tends toward an initial extensional back arc envirenment. It appears that partial melting of adjusted mantle wedge above a subducted slab provided the parental magma which was enriched by fluids-melt released from partial melting of the subducted slab. Manuscript profile -
Open Access Article
5 - Investigating of seasonal change effects on suspended sediment yield using geochemical tracers
Kazem Nosrati فروزان احمدیThe objective of this study is to investigate the effect of seasonal changes on erosion and sediment yield in land-use types in Taleghani catchment, using the fingerprinting technique. In view of this, 39 soil samples including 17, 12, and 10 samples were collected from MoreThe objective of this study is to investigate the effect of seasonal changes on erosion and sediment yield in land-use types in Taleghani catchment, using the fingerprinting technique. In view of this, 39 soil samples including 17, 12, and 10 samples were collected from different sources: agriculture, rangeland, and forest, respectively. 7 samples also were collected from suspended sediments in two different seasons (3 samples in autumn and 4 samples in spring) from 2012 until 2013. After preparing the samples, 11 tracers including C, N, P, Na, K, Cu, Zn, Mg, Mn, Fe and Ca were measured as the primary tracers in sediment sources and sediment samples. Based on Kruskal-Wallis test and discriminant function analysis, four tracers including Mg, C, Zn and Ca were selected as the optimum set of tracers that can discriminate 3 sediment sources. Then sediment source samples were compared with suspended sediment samples. The results showed that the contribution of sediment sources is 67.9%, 32.1%, and 0 percent for agriculture, rangeland and forest, respectively in autumn season and the contribution of sediment sources is 44.3%, 44.3% and 11.4% for agriculture, rangeland, and forest, respectively in spring season. These results indicate the role of human activity on the erosion rate and land-use types as a very important factor in accelerating the erosion and sedimentation process in Iranian basins. Manuscript profile -
Open Access Article
6 - Biostratigraphy of the Sarvak and Ilam formations in Abteymoor Oil Field (Wells no. 1 and 14)
Reza Omidi Mahmoud Jalali Mahboubeh Hooseni-barzi Narges AkbariIn order to carry out biostratigraphic studies on Sarvak and Ilam formations, two subsurface sections in wells 1 and 14 of Abteymoor oil field were selected in the south of Dezful embayment. Sarvak Formation in well #1 has 812.98 (m) thickness and in Well No. 14 only 23 MoreIn order to carry out biostratigraphic studies on Sarvak and Ilam formations, two subsurface sections in wells 1 and 14 of Abteymoor oil field were selected in the south of Dezful embayment. Sarvak Formation in well #1 has 812.98 (m) thickness and in Well No. 14 only 234 (m) of this formation was drilled, in terms of lithology the Sarvak Formation consists mainly of limestone with dolomitic and clay interbeds. Its lower boundary in Well # 1 with Kazhdumi Formation is conformable but in Well # 14 it is unclear. The upper boundary is disconformable with Ilam Formation in both wells. Ilam Formation in two wells of 1 and 14, has thickness of 151.72 and 136 (m) respectively and in terms of lithology, it consists of limestone and shaley, marly and dolomitic limestone interbeds. The upper boundary of Ilam Formation with Gurpi Formation is conformable with sharp changes in lithology. In biostratigraphy studies 71 species were detected which belong to 57 genera of foraminifera, a biozones (biozone 1) in Ilam Formation and three biozones (biozones 2, 3 and 4) were identified in Sarvak Formation. They include: 1- Rotorbinella-Pararotalia Assemblage Zone 2- Nezzazatinella picardi-Dicyclina schlumbergeri Assemblage Zone 3- Rotorbinella mesogeensis Total Range Zone 4- Nezzazata-alveolinid Assemblage Zone Based on identified biozones, age of Sarvak Formation is considered as Cenomanian- Turonian and the age of Ilam Formation is Designated as Santonian- Campanian? Manuscript profile -
Open Access Article
7 - Sequence Stratigraphy of Oligo-Miocene deposits at Ahmadi anticline, southeast of Shiraz
Jahanbakhsh Daneshian Mohsen Yaghoobi Alireza Tahmasbi SarvestaniThe sequence stratigraphic studies can be of great help in understanding and analysis of sedimentary basins. For this purpose, Oligo-Miocene sediments (Razak and Asmari formations) at the Tang-e-Abdi section (southern flank of Ahmadi anticline) located in Fars province MoreThe sequence stratigraphic studies can be of great help in understanding and analysis of sedimentary basins. For this purpose, Oligo-Miocene sediments (Razak and Asmari formations) at the Tang-e-Abdi section (southern flank of Ahmadi anticline) located in Fars province was selected and investigated. The Asmari Formation overlies paraconformably on the Jahrum Formation, and it is overlain by the Razak Formation. The lithologic column of this section includes a succession of the Jahrum (10m), Asmari (35m) and Razak (172.5m) formations, and consists mainly of limestone, argillaceous limestone, marl, sandstone, conglomerate, shale and dolomitic deposits. Totally, 84 samples were investigated, and their age is suggested as Late Eocene for the Jahrum Formation to Rupelian for the Asmari sediments, and Rupelian to Aquitanian for the Razak Formation based on the benthic foraminiferal stratigraphic distribution. The microfacies studies were led to recognition of four facies belts including tidal flat, lagoon, sand shoals and open marine. According to field & laboratory studies, four sequences and sequence boundaries were recognized. Two sequence boundaries are of type one and the other two are of type II sequence boundaries. Manuscript profile -
Open Access Article
8 - Ability of Felmann wells to improve the physical and microbial parameters of river water
Mojtaba G.Mahmoodlu Mostfa Seyed Seyd Mostafa Khezri Gholam Abbas Fanaei KheirabadRiverbank filtration can be used as an effective and low-cost method for water treatment of rivers for drinking purposes. In alluvial land consisting of loose sediments (e.g., sand or gravel) with a water table near land surface, one of the most economical methods for e MoreRiverbank filtration can be used as an effective and low-cost method for water treatment of rivers for drinking purposes. In alluvial land consisting of loose sediments (e.g., sand or gravel) with a water table near land surface, one of the most economical methods for extracting water in large volumes is the use of wells with large diameter such as Felmann Well. In this study, we investigated the effect of Felmann Wells and riverbank filtration process on improving the water quality parameters of surface water. For this, Doogh River and a Felmann Well were sampled simultaneously within a 5-month period. SPSS software and T-tset were used to determine the significant difference between data obtained from chemical analysis. Comparison of water quality parameters of Doogh River and Felmann Well showed that riverbank filtration can play an important role in reducing the physical and biological parameters of water in Felmann Well drilled near the river. For drinking water purpose, the water quality of both Doogh River and Felmann Well was investigated using WQI (Water Quality Index). Hence, the WQI for Doogh River water varied from 50 to 57, which indicated the average quality of the water of the Doogh River. While, WQI value varied from 64 and 75 for the Felmann well representing a good water quality in the well. Results of this study showed that the Felmann wells which were drilled near the riverbank can play an important role in improving the water quality parameters of surface water for drinking purposes. Manuscript profile