Stratigraphy and Palaeontology
Fatemeh Rezvannia; Hossein Mosaddegh; Bijan Biranvand; Vahid Tavakoli; Galina Nestell; َAhmad Yahyaei
Abstract
One of the most important carbonate gas reservoirs in the Zagros and Persian Gulf sedimentary basins is the Dalan Formation. This research investigates the microfacies, lithostratigraphy, and sequences of carbonate-evaporite deposits in the Lower member of the Dalan and the Nar member belonging to the ...
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One of the most important carbonate gas reservoirs in the Zagros and Persian Gulf sedimentary basins is the Dalan Formation. This research investigates the microfacies, lithostratigraphy, and sequences of carbonate-evaporite deposits in the Lower member of the Dalan and the Nar member belonging to the Guadalupian series with a total thickness of 2402 meters in four wells namely A, D, E, and G located in the eastern part of the Qatar-Persian arc in the Persian Gulf. The study of 340 thin sections prepared from the drill-ing cutting pieces with 2-meter intervals of well E, and a review of documents related to other wells. this led to the identification of 20 species belonging to 14 genera of foraminifera and the foraminiferal assemblages consisting of 65 species belonging to 25 genera. A foraminiferal biozone was recognized in well E, assigned to the Wordian. - Capitanian: Pachyphloia- Globivalvulina- Hemigordius, Assemblage Zone. Additionally, 11 microfacies, are distributed in five environments (sabkha, intertidal, lagoon, shoal, and shallow marine).
F Behravesh; M.H Mahmudy Gharaie; F Ghassemzadeh; S Avaz Moghaddam
Abstract
Traffic dust often contains high concentrations of heavy metals and can influence on environment and human health. In this study, we tried to measure heavy metals in street dusts and soil in the city of Mashhad and sample collections were carried out at the time and location of high traffic. For the ...
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Traffic dust often contains high concentrations of heavy metals and can influence on environment and human health. In this study, we tried to measure heavy metals in street dusts and soil in the city of Mashhad and sample collections were carried out at the time and location of high traffic. For the purpose of this study, twenty three samples were collected from three main paths that cover the entire city and total concentrations of five heavy metals (Ni, Zn, Pb, Cr, and Cu) were measured. The index of geo-accumulation (Igeo), Pollution index (PI) and integrated pollution index (IPI) were also calculated for the contamination levels of the metals in the city of Mashhad,. The pollution index represent that all samples are highly polluted by Pb (3.688-74.16) and most of the samples are highly polluted by Zn (1.484-7.23). However, Cu (0.678-1.945) and Ni show medium level of pollution in the samples (1.01-1.935). Chromium in all samples show low levels of contamination (0.246-0.772). Possible sources of the pollutants were assessed using Pearson correlation and principal components analysis. The results of this analysis show high concentrations of metals such as lead, copper, zinc and nickel in the soil samples as compared to UCC (Upper Continental Crust). There is a positive correlation between heavy metals of zinc and copper as well as lead and zinc, which indicate the source of these metals, can be fuels as well as powder of shoe brake of vehicles. The results of the sequential extraction procedure also imply that the elements of Ni, Zn and Pb has occurred in unstable phases (F1+F2+F3+F4), indicating their human origin. But the elements such as Cr and Cu are mainly on stable phases (F5), which represents natural origin for these two elements.
K. Seyed Emami; N. Behfar; M. R. Majidifard; A. Behfar
Abstract
Middle Jurassic strata are well developed northeast of Damghan (E Alborz). At the study section the Dalichai Formation has a maximum thickness of 156 m, consisting of an alternation of bluish-grey limestones and marls, being subdivided into 4 members. The lower boundary with the siliciclastics of the ...
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Middle Jurassic strata are well developed northeast of Damghan (E Alborz). At the study section the Dalichai Formation has a maximum thickness of 156 m, consisting of an alternation of bluish-grey limestones and marls, being subdivided into 4 members. The lower boundary with the siliciclastics of the underlying Shemshak Formation is unconformity, due to the Mid-Cimmerian tectonic event, whereas the upper boundary with the light and cliff-forming carbonates of the Lar Formation is gradational. The Dalichai Formation at the study section is very fossiliferous. Summing up 1750 fossil specimens were collected, among which the ammonoids with 1491 specimens clearly predominate. Altogether 27 genera, 33 species of ammonites, belonging to 6 biozones (Parkinsoni Zone, Zigzag-Aurigerus zones, Subcontractus Zone, Bullatus-Gracilis zones, Anceps-Coronatum zones, Athleta Zone) has been recognized. In addition 17 genera and 8 species of planktonic and benthic foraminifers are described.These can be divided into 2 biozones. The fossil-content is mainly concentrated within few meters of red and nodular limestone in the upper part of the section. Based on the ammonite fauna the age of the Dalichai Formation in the investigated area ranges from Upper Bajocian to Oxfordian. Paleobigeographically the fauna shows close relationship to western Europe and Sub-Mediterranean region. This indicates a paleogeographic position of the area at the northern Tethys during the Middle-Upper Jurassic.
S. Shariati; S. A. Aghanabati; S. R. Mousavi Harami; S. Modabberi; M. H. Adabi
Abstract
Angouran Lead and Zinc Mining deposit is one of the biggest Lead and Zinc deposits of Middle East and one of five great mines of Iran according to the article of categorization of the mines of Iran. In addition to the diverse metal and non-metal mines, there are many industries and factories in this ...
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Angouran Lead and Zinc Mining deposit is one of the biggest Lead and Zinc deposits of Middle East and one of five great mines of Iran according to the article of categorization of the mines of Iran. In addition to the diverse metal and non-metal mines, there are many industries and factories in this region which most of them were active and are as conversion industries of Zinc soil into the Concentrate or as factoring of Lead and Zinc Bar. The realized studies demonstrate that due to activation of existent industries in that region, the rate of some elements are in unusual level and show some fundamental environmental abnormalities. The environment of the region is mostly influenced by the accumulation of wastes and residues dispossessed as cake in the borders of the rivers and canals and open lands. These Cakes which as a matter of fact are the residues of proceeding of the flotation and melting the Lead and Zinc and the process of Concentrate factoring, may have lost the great amount of their Lead and Zinc in the industrial point of view, but as an environment view, those have a lot of Lead and Zinc many times more than allowed limits which are potentially toxic. At the other hand, by reduction of these elements, the densities of other elements are increasing. This means intensive effects which in this paper are going to be surveyed. The rates of these elements in some samples are reported exceeding to 10,000 ppm Lead and Zinc and Nickel and also 8,000 ppm Arsenic and 4,000 Cadmium. The studies also demonstrate that waste pool or the pools of residues are one of the most fundamental causes of dangers for the environment of the region. The rate of 200,000 ppm of Zinc and sometimes 2000 ppm of Lead and 20,000 ppm Nickel, also tha rate of some hundreds ppm of arsenic and even 200,000 ppm of Cadmium in the water and water deposits of the region are some of those dangers. The most of these abnormalities are seen in the sediments and water of the region, however the agricultural grounds are also influenced by these pollutions and are included some major abnormalities in term of the environment. This paper will exclusively review the allowed rate of the elements of Lead, Zinc, Cadmium, and Arsenic and survey the principal manners of access of these elements to the environment of region and also try to present some solution for the control and reduction of these rates.
S. R. Shadizadeh; M. Zoveidavianpoor
Abstract
Abadan Refinery is located between Arvandrud and Bahmanshir rivers. These rivers supply urban, industrial and agricultural water of Abadan city. During the war between Iran and Iraq, leakage of large amounts of oil and its refined products from storage tanks, pipe lines, and refinery units of Abadan ...
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Abadan Refinery is located between Arvandrud and Bahmanshir rivers. These rivers supply urban, industrial and agricultural water of Abadan city. During the war between Iran and Iraq, leakage of large amounts of oil and its refined products from storage tanks, pipe lines, and refinery units of Abadan refinery to surrounding environment occurred. Also, leakage of petroleum and its products during the operation of Abadan refinery to surrounding environment led to conduct a research for determination of oil pollution extension of underground layers in Abadan refinery. Utilization of clays as natural geological barriers in environmental application and pollution control has been widely recognized. Abadan city was formed by recent Estuarine; these alluviums had a diverse variety in grain size and material. In the case of dominant presence of clay in underground layers, petroleum pollution control hypothesis of Abadan refinery is confirmed. In order to prove the above hypothesis the following items were conducted: 1) determination of material type of underground layers, 2) determination of petroleum pollution in underground layers and defining the oil saturation of the cores, and 3) determination of petroleum pollution in underground waters by one year sampling of underground waters along with measurement of piezometric head of groundwater monitoring wells. Location of twenty groundwater monitoring wells was investigated by considering petroleum leakage to surrounding area during and after war. Geological underground layers of Abadan refinery was determined from coring during drilling of the groundwater monitoring wells. The results of this investigation has shown that the material type of underground layers of Abadan refinery had a significant role to encapsulate petroleum leakage, in such a manner that leaked petroleum was observed in all of the drilled boreholes. On the other hand floated leaked petroleum on groundwater was observed just in two groundwater monitoring wells. These two polluted groundwater monitoring wells were shown to be from leakage of recent activities of Abadan refinery. Finally the results show that the majority of existing petroleum in underground layers of Abadan refinery was absorbed by clay