kamal siahcheshm

The Niaz Cu prospect is located 25 km west of Meshkinshahr, east of the Qaradagh metallogenic zone. The intrusion Oligo-Miocene magmatic bodies into the Paleocene-Eocene rock units has led to alteration and mineralization. The rock units of this area include batholiths Ι and ΙΙ (Khanbaz granodiorite and Khankandi granodiorite), Niaz quartz-monzonite/ quartz-monzodiorite and ore-bearing rhyodacite breccia.

In this research, the geological features, alteration, mineralization and physicochemical conditions of mineralizing fluids have been studied. In this regard, sampling from altered, mineralized zones and drilling cores were carried out and 23 samples were analyzed by XRF and 18 samples by ICP-OES methods and microthermometric measurements were performed on 8 doubly-polished thin sections.

The intrusive units have high-K calc-alkaline to shoshonitic nature, and the geochemical characteristics of their trace elements indicate similarities with subduction-related magmas. The negative anomaly of Ti and Nb in these rocks can be due to the magmatism related to the subduction processes, as well as the stability of the phases containing these elements during partial melting or their separation during the differentiation process. The enrichment of Pb, La, K, U, and Th elements and the depletion of Sr, Ti, and Nb can be attributed to crustal contamination. Hypogene alterations at Niaz include potassic, phyllic, propylitic and intermediate argillic types. Mineralization has occurred during early, middle, and late stages. Based on the mineralogy and paragenetic sequence, at least five types of veins/veinlets can be distinguished in Niaz deposit. Group A veinlets contain quartz+pyrite+chalcopyrite+magnetite, group B veins are also present in the potassic and phyllic alteration zones, veinlets of group C are mainly formed in the middle stage of mineralization, group D veins are mostly observed in the phyllic alteration zone, which are formed in the middle and later stages of hydrothermal activities and group E veins are almost devoid of sulfide minerals and mainly contain bright-color minerals (quartz and/or calcite)±tourmaline and are mostly present in the propylitic alteration zone. Studies on fluid inclusions (FIs) within the quartz veinlets showed that there are four types of FIs at room temperature, (1) mono-phase vapor, (2) liquid-rich 2-phase, (3) vapor-rich 2-phase, and (4) multi-phase solid containing daughter solid phases. The ranges of FIs are about 280-360°C in the potassic, 280-360°C and 280-300°C in phyllic and 170-330°C in propylitic alteration zones.

The petrology and petrogenesis of magmatic host rocks, mineralogy, hydrothermal alteration in the Niaz area testify to a porphyry-type Cu mineralization. The main sulfide mineralization includes vein-type pyrite, molybdenite, chalcopyrite, sphalerite and galena. Fluid inclusion microthermometry results show a Th range of 170-360 °C and salinity values of 0.2-60 wt%NaCl equiv., corresponding to the ranges of porphyry Cu deposits. Boiling and simple colling of ore-bearing fluids were the main processes for ore precipitation.

Alam-Kandy iron skarn lies at the contact margin of a granodiorite stock with limestone and dolomites of Soltanieh Formation. Anhydrous prograde calc-silicate assemblages (garnet, diopside, wollastonite) were replaced by a series of hydrous calc-silicates (serpentine, epidote, tremolite-actinolite) and/or quartz, calcite, magnetite, hematite, and pyrite. During this event, magnetite lenses (±hematite and pyrite) are formed with various textures such as massive, banded, scattered grains and veins at the vicinity of the intrusion body and the contact zones. According to this study, The geochemistry of trace elements of magnetite is variable under the influence of progressive and regressive stages of skarn formation and wall rock composition, and consistant with the indicators of magnetite formation in the (magnesium) skarn environment. These include factors such as: 1) high concentration of Mg (1 to 1.5 %), low values of Cr (<10 ppm), Ti (<0.01%) and insignificant incompatible elements such as Ag (0.5 ppm) 1 <), Rb (ppm 1 <), Sb (ppm 1 <) and Na (less than 0.1%) in magnetite; 2) significant positive correlation between Ti and V and the position of the samples in the Ti+V versus Ca+Al+Mn and Ni/(Cr + Mn) diagrams. High temperature vein-veinlet magnetites have more cobalt content than the replacement magnetites syn-deposited by sulfide minerals (retrograde stage), indicating that in the Alam Kennedy skarn system, the concentration of cobalt in the magnetite is controlled by the abundance of sulfide mineral deposits.

The Sarikhanloo area is located within the Qaradagh metallogenic zone in northwest Meshgin Shahr. Igneous rocks cropped out in this area include successions of Paleocene-Eocene pyroclastic rocks (tuff and andesitic-dacitic lavas with intercalations of ignimbrite) and basaltic andesite lava flows. Igneous rocks show high-K calc-alkaline to shoshonitic nature and are mainly metaluminous, formed in a post-collisional uplift tectonic setting. Hydrothermal activities in this area brought about formation of vast silicic veins and caps, along with silicic, propylitic, phyllic (non-pervasive) and intermediate argillic alterations around the veins, as well as intermediate to advanced argillic alteration halos at the margins of silicic caps. Ore minerals in the silicic veins includes pyrite, arsenopyrite and Fe-oxides, accompanied by minor malachite, formed during four mineralization stages. Fluid inclusion studies indicate that the homogenization temperature of fluid inclusions ranges from 175 to 355 °C, considering the low pressure of fluid inclusions (≤ 0-40 bars), can signify the fluid temperature at the time of entrapment. The estimated salinity values are between 0.2 and 3 wt% NaCleq.

Oxidation of sulfide mineralized zones during the weathering processes is intensified by biological and chemical reactions and the resulting acid mine drainage (AMD) causes the release and mobility of toxic and heavy metals from the parent rock and their concentration in soil or water. In this study, soil samples taken from around the village of Doustbaglu (northwest of Meshginshahr), which is considered a typical mineralization and alteration area, were studied and chemical species, toxicity and origin of heavy elements such as As, Cd, Cu, Cr, Pb, Sb, Ni and Zn were determined.

In this study, total concentration and bioavailability of heavy elements (i.e. As, Cd, Cu, Cr, Pb, Sb, Ni and Zn) in five surface soil samples were evaluated by Tessier sequential extraction method in five phases (exchangeable, bound to carbonate, bound to iron and manganese oxides, bound to organic matter and residual phase) and using of the Visual Minteq thermodynamic software.

The results of the sequential extraction method show that the highest concentration of the total concentration of all 8 heavy elements studied were retained in the residual fraction (stabilized in the mineral structure). This indicates the geogenic origin of these elements and can be considered the result of erosion and weathering of rocks in the region. Compared to other elements, Sb has a higher concentration in potentially available fractions (e.g. exchangeable, carbonate-bound, bound to Fe-and Mn-oxides, and/or organic matter) and can be readily available to plants and toxic. The software output delineates that the predominant species in the examined samples were lead (Pb) as Pb (SO4)22-, Pb2+ and PbSO4(aq); copper as CuSO4 (aq) and Cu2+; nickel as NiSO4 (aq), Ni2+ and NiSO4; antimony as Sb(OH)3, Sb(OH)2+ and Sb(OH)61-; zinc as Zn(SO4)22-, ZnSO4(aq) and Zn2+; Arsenic as H3AsO3 and H2AsO4-; Cadmium as Cd(SO4)22-; and Cd2+ The predominant species of chromium were CrSO4+, CrOHSO4(aq) and HCrO4-. In general, the free water-soluble species of these elements are more mobile than other species; instead, the concentration of these species is very low in comparison, and most of these elements are more present in the form of complexes with low mobility.

 Based on sequential extraction results; all 8 studied elements show high ecological risk potential and significant pollution in the sediment of waterways and surface soil horizons of the Doustbaglu area. Analysis of the findings of Visual Minteq software indicates that the most active types of elements and related concentrations, among all possible types, include: Cd2+(1.49%), CrOHSO4(aq)(25.20%), Cu2+(10/38%), Pb2+(1/37%), ZnSO4(aq) (18.83%), respectively. Since more mobile species have low concentrations and on the other hand, according to the results of sequential extraction, most of the studied elements are present in the remaining phase, so the bioavailability and toxicity of these elements are estimated to be negligible. In general, it can be concluded that only a small percentage of elements are present in bioavailable fractions, and this can alleviate concerns about the possibility of element release by changing environmental conditions and thus accessibility to plants.

The monzonitic-syenitic Gowdal intrusive body located in the north of Ahar, East- Azerbaidjan province is a member of the Shivardagh batholithic body and a part of the Alborz- Azerbaidjan- Lesser Caucasus magmatic belt related to the Meso-Tethys (Sevan- Akera- Ghareh Dagh) Ocean. Fe- Cu and Mo skarn mineralization (magnetite, specularite, pyrite, chalcopyrite, and molybdenite) occurred at the contact of the Gowdal intrusive body with limestone- marly limestone units. The supergene copper and iron minerals (malachite, azurite, secondary hematite, and Fe-hydroxides) are superimposed on the hypogene skarn mineralization assemblages. Based upon diagrams of major elements versus SiO2, with mean values, ratios of trace elements, and diagrams of trace elements, the Gowdal intrusive body formed from relatively evolved magma and compositionally lies within the range of intrusive bodies affiliated with copper and to some extent zinc skarns. On the other hand, distribution patterns of trace elements of the Gowdal intrusive body normalized to N-MORB shows considerable similarity to known zinc and to some extent copper skarn-related intrusive bodies. Consequently, despite having dominant iron mineralization at the current level, the Gowdal intrusive body displays the utmost similarity with the bodies associated with copper skarns.

Phytoremediation can be one of the most promising techniques for elimination of pollutants from water and soil and environmental management. Through absorption and desorption processes, we can determine the level of maintenance for cations and anions. Based on transition factor of elements it is possible to specify that elements like Barium and Lithium have the least and elements like Cadmium and Boron have the highest accumulation. Soil pH also affects the level of availability and mobility of elements by controlling solubility of soil organic matters and it is in direct relationship with oxidation and reduction conditions. Absorption of ions by plant roots can be both passive (in direction of diffusion gradient) and active (against diffusion gradient using energy) processes. Phytoremediation is accomplished in four states including 1) phytostabilization and deposition of pollutants in the root, 2) phytoextraction that can be divided into two categories: continuous that requires the use of plants throughout their lifetime and induced by addition of accelerants or chelators to the soil, 3) phytovolatilization and transfer of contaminants from the root to leaves and the atmosphere and 4) phytofiltration to remove contaminants from water. For instance, to remove Arsenic, Cadmium (Zinc), Chromium, Mercury, Nickel, Lead, and Selenium plants such as P. vittata, T. caerulescens, Betula sp. tree, Amanita muscaria, Alyssum lesbiacum, Arabidopsis sp., and B. juncea could be used respectively.

Oxidation of sulfide-mineralized zones during weathering intensifies by the biological and chemical reactions, and the released acidic mine drainage (AMD) mobilizes toxic and heavy elements from the parent rock and concentrates them in soil or water environments. The village of Doustbaglu is located in a mountainous area to the northwest of Meshgin-Shahr city, which has numerous farmlands overlooking the extensive alteration zones. Field studies indicate that, unfortunately, skin and liver diseases, as well as cancer are prevalent in the area. The importance of knowledge of heavy metal enrichment in soil resources and the high potential of the Doustbaglu area for the production of agricultural and horticultural crops and its direct relationship with human health reveals the necessity of conducting this study to evaluate heavy metal contamination and identify possible sources.

In this study, the total concentration and bioavailability of heavy metals including As, Cd, Cu, Cr, Pb, Sb, Ni, and Zn in 70 surface soil samples were evaluated by ICP-MS analysis. Calculation of contamination rates of soil samples was done using different environmental indices including modified contamination index, soil heavy metals ecological risk index, pollution load index, and Nemerow’s index.

The results of the mCd index showed a high degree of contamination of Cu, Cr, Cd, Pb, Sb, Ni, Zn and as in most samples. High values of the ecological risk index (up to 2076.9) indicated the level of serious contamination risk of some samples. The pollution load index (PLI) in 10 samples showed PLI values <1 indicating no contamination of the samples, but in other samples, high loads of heavy metal contamination were observed in the soil of this area. According to Nemerow’s index, Cu, Pb, Sb, As, and Cd were highly contaminating. Statistical analysis of data and calculations of correlation coefficients, cluster analysis, and PCA test (VARIMAX rotation) revealed a positive and significant correlation between elements such as Pb with Cr, As and Sb, Ni with Cr, Cd and Zn and a negative correlation with arsenic. Therefore, it is estimated that these elements have a similar and predominantly geogenic origin.

Based on the results of geo-environmental indices, all eight studied elements showed high ecological risk potential and significant contamination occurrence in stream sediments and surface horizons of the Doustbaglu district.

The Aghbolagh iron-copper skarn is located in ~21 km north of Oshnavieh, southwest of West-Azarbaidjan province. The intrusion of Cretaceous granitic body into the Cambrian Barut, Zagun, and Lalun Formations (carbonate, shale, and sandstone) was accompanied by development of calcic-type skarn, hornfels, and marble in the study area. The garnets of the Aghbolagh skarn belong to solid solution series of grossularite-andradite in which andradite is the dominant phase (>80%). These garnets are isotropic and lack zonation. The pattern of REE distribution in these garnets shows the enrichment of LREE relative to HREE and also the occurrence of negative anomalies of Eu/Eu* and Ce/Ce*. The comparison of the distribution pattern of REE in garnets with those in igneous (granite and monzonite) and sedimentary (carbonates and sandstones) rocks demonstrates that the REE in garnets were derived mainly from the igneous rocks rather than the sedimentary units. The increase in Pr/Yb ratios in parallel with increase in the ƩREE is indicative of the magmatic origin of the ore-forming fluids in the Aghbolagh skarn. However, the lack of sensible variations between Ce/CE* and ƩREE values indicate that the meteoric waters might have also played a part in skarn-forming fluids at Aghbolagh.

As a result of mining activities in Sungun copper mine at the north of Iran acid mine drainage enters into Pakhirchay river a subbasin of Aras borderline river. In this study using laboratory and modeling studies, optimal method is provided for treating acid mine drainage. First dynamics laboratory model was employed to evaluate zeolite efficiency to remove the copper and then using a static tests the maximum absorption potential was estimated 2.85 mg/L. Thus a zeolite filter with a length of 250 m was considered for removal of copper from the acidic drainage. For simulation copper ion transport HYDRUS 2D model was employed to investigate behavior of contaminants in porous media with a body of zeolite and also evaluate efficiency of zeolite on reducing of copper concentration under various scenarios. First scenario showed for the present condition of the drainage zeolite will decrease Cu concentration down to sub-standard copper concentration (5 mg/L) for two months. In the second scenario, as the worst case scenario, it was assumed that the concentration of copper ion increase 50% of the initial value. The model revealed that filter is able to keep the copper level below the standard level only for a month. Finally, under the last scenario and also the most optimistic one that the entering copper is ceased a month after the implementation of the model, zeolite filter will absorb copper ions for two months, without needing to change the filter material.

Nowadays, the use of bacteria to clean oil pollution from water and soil has been considered by scientists and this method is more economical than other methods and does not cause toxic compounds in the environment.

In the present study, the results of the bioremediation process have been presented to identify the most optimal bacterial isolates of petroleum degraders in physicochemical and textural conditions of contaminated soil of Tabriz refinery. Gas chromatographic analysis with thermal detection (Gc-FID) was used to evaluate the removal rate of hydrocarbons.

The 7 isolates of bacteria were purified in this study. A Pseudomonas isolate was introduced as a strain with the highest efficiency.

 Discussion and Conclusion

After 30 days, as a result of Pseudomonas and Acinetobacter performance, the amount of TPH in contaminated soil samples was decreased in rate of 65.25 and 42.39 percent, respectively. Based on this investigation, the Bacterial Bioremediation method to clean up contaminated soils by petroleum hydrocarbons due to simplicity of implementation, environmentally friendly, safety and low cost is highly proposed to conduct in other oil refineries in Iran.

The Noghduz  prospecting area, as a part of the Arasbaran metallogenic zone is located about 20 km east of Ahar, East-Azarbaijan Province. The mineralization host rocks are andesite-trachy andesite with the age of  Late  Eocene. The hydrothermal alterations exposed in this area are silicic, argillic, and propylitic. Pyrite is the main hypogene sulfide mineral which is accompanied by lesser amounts of chalcopyrite and bornite. The most important supergene minerals in this area are iron oxyhydroxides (hematite, limonite and goethite) and malachite that accompany the hypogene mineral assemblage. Gold mineralization occurred within quartz-sulfide veins/veinlets in this area. The microthermometric measurements in the primary 2-phase (L+V) fluid inclusions in quartz crystals associated with  mineralization  indicate that  the mineralizing fluids had temperatures and salinities within the range of 160-334°C and 0.53-3.39 wt% NaCl equivalent. respectively. The presence of hydrothermal breccias, pseudomorph of quartz after bladed calcite, and mono-phase gas inclusions are indicative of boiling of the hydrothermal fluids responsible for mineralization. The sulfur isotopic analysis of pyrite shows  that  the values of isotopic composition of this element  is  close to the range of magmatic source. Also, the oxygen and hydrogen isotopic data demonstrated that  the meteoric waters constituted a great portion of the ore-bearing fluids at Noghduz area. The presence of structural and textural evidence along with fluid inclusion studies (salinity and homogenization temperature) indicate that the gold mineralization at Noghduz area is of epithermal type.

The Malayer-Boroujerd-Shazand district (approximately 70 km long) is located in the Sanandaj-Sirjan zone with NW-SE trending, and consist mainly of hornfels, schist, phyllite, migmatite, granite and granodiorite which contain numerous pegmatite and aplitic dykes. Among these rocks, granodiorite, hornfels and schist are main host rocks for quartz, feldspar, muscovite and tourmaline bearing pegmatites. The tourmaline composition is schorlite- foitite type with tendency to dravite in Shazand tourmaline which show magmatic-hydrothermal origin, and located in alkali and site-vacancies. These tourmalines in the Fe/ (Fe + Mg) vs MgO diagram are located above and below 0.8 which proved tourmalines are magmatic and hydrothermal. Magmatic evidences are dominantly schorlite tourmaline composition, increase in octahedral Al content, higher Fe content than Mg and presence of more sample between alkali-deficient and proton-deficient tourmaline vectors. Presence of zoning in tourmaline, vein form pegmatite, increase of Mg in some samples and being away from alkali-deficient and proton-deficient tourmaline vectors are evidences for hydrothermal origin of tourmaline.

The Zailic gold-bearing veins are located in the Arasbaran metallogenic zone, east of Ahar, East-Azarbaidjan Province. The most important lithologic units in this area are andesitic and trachy-andesitic tuffs and lavas of Upper Eocene age hosting vein-type gold mineralization. Theses rocks have suffered silicic, argillic, phyllic, and propylitic alterations brought about by hydrothermal fluids. The geochemical study of alteration zones in this area showed that in the silicic zone, due to the acidic nature of altering fluids and hence intense leaching, depletion of most major and trace elements took place. The degree of leaching towards the propylitic zone, owing to the pH increase of the hydrothermal fluids, gradually decreases. The presence of minerals with high adsorption capacity, such as clay minerals, resulted in concentration and fixation of many elements in the argillic, phyllic, and propylitic zones. Consideration of the behavior of rare earth elements (REE) in silicic zone relative to almost fresh volcanic rocks showed that most of REE suffered depletion. Geochemical indices such as TiO2 and (Ce + Y + La)-(Ba + S), showed that the hypogene hydrothermal fluids played an important role in the development of alteration zones at Zailic

The Shirbit polymetal prospect area is located in 30 km north-east of Ahar city within the Ahar- ore filed in around of Shivardagh batholith. Intrusion of granodiorite igneous bodies into the Eocene trachyte to andesite associated with pyroclastic interlayers caused widespread silicic, argillic and propylitic hydrothermal alteration associated with the Cu, Mo, Pb mineralization as quartz-sulfide (±oxide, carbonate, sulphate) vein and veinlets. Most of chalcopyrite, pyrite and molybdenite veins together with malachite, azurite and iron hydroxides were concentrated in the trachytic-andesitic units with silicic-argillic alteration. The turning point of this study includes investigating the possibility of log-log C-P method for separating geochemical anomalies of ore forming elements from the background, accurately determining the cut-off grade, decreasing the area of anomalies, and determining the number of stages of enrichment of elements in the study area compared to the multivariate statistical methods. For this purpose, 85 stream sediment samples taken from a systematic geochemical network were analyzed using ICP-MS method. In order to identify the susceptible mineralization areas by using of concentration-perimeter double logarithmic method, thee background values and anomalies were separated for each element in the region. Then, elemental anomaly maps were prepared and finally the distribution maps of the ore-forming elements were mapped and the relevant anomalies were distinguished. The results of using C-P fractal method indicates the presence of possible anomalies of Cu, Mo and Ti elements in the eastern, northeastern, and southwest parts of Shirbit area.

Khak- Sorkh iron deposit lies about 42 km west of the Yazd city. The area is located in the central part of the Urumieh-Dokhtar magmatic belt and is covered by upper Triassic-lower Jurassic sedimentary units and Oligo-Miocene intrusions. Intrusion of Oligo-Miocene granitoids into Cretaceous limestones resulted in iron skarn mineralization. Magnetite is the main iron ore mineral; minor copper mineralization also occurs locally as malachite staining at surface. Two main structural trends can be distinguished: NW-SE which follows the main trend of the Urumieh-Dokhtar belt, and NE-SW trend that transects the former one and dissects magnetite bodies in some places.
In this study Euler deconvolution and analytical signal methods have been used for interpretation of geophysical data. Depth of magnetic anomalies determined by Euler deconvolution clarified that magnetic bodies are located at shallow depths in the NW of the area. The trends of the detected anomalies correlate very well with the general trend of the Urumieh-Dokhtar belt. This can be used as an exploration tool for magnetic anomalies in the area and likely in other parts of the Central Urumieh-Dokhtar belt. Based on magnetic anomalies 15 diamond bore holes were drilled at the NW part of the region which cut the ore bodies at predicted levels with average ore assay of 39 percent total iron.

The study area is located about 25 km northwest of Takestan city, within Tarom-e-Sofla metallogenic belt. This area is covered by a widespread Eocene andesite to dasite volcanic rocks affected by Oligo-Miocene monzogranite to granodiorite igneous bodies which altered them to silicic, argillic zones as long as hypogene sulfide vein-veinlet mineralization (e.g. galena, sphalerite, pyrite, rare chalcopyrite and tetrahedrie- tennantite) occurred along with supergene minerals (e.g anglesite, cerussite, malachite, covellite and goethite in oxide zone). This study concentrated on geochemistry and geo-barometry of sphalerite and galena to evaluate sulfidation state, temperature and type of ore formation. During mineralography studies, two types of galena were recognized: 1) high temperature, brecciated veinlet type including tetrahedrite and, 2) low temperature coarse grained type along with colloform sphalerite. Based upon mineral chemistry of sphalerite, average concentration of Cd, Ga, Ge, Zn/Cd and Ga/Ge ratios were 5870, 970, 1380, 165.4 and 1.39, respectively. Ga/Ge ratios of sphalerites geothermometry indicate that the formation temperatures of sphalerite are between 170°C and 220°C. The amount of log aS2 hydrothermal fluid (-11.5 to -13.5), calculated from FeS content (0.33-0.80 mol%) in sphalerite, can be attributed to moderate sulfidation state for changoreh deposit. According to Sb/Bi in galena geo-thermometer, geochemistry of sphalerite (low ∑Sred activites, moderate Cd content (5870 ppm) and average Zn/Cd ratio (165.4), physico-chemical and thermodynamics of ore-bearing fluid in Changoreh is in accordance with moderate to high temperature epithermal deposits.

In order to assess soil pollution formed on the alteration zones of Zakhur District, we used 20 ICP-MS analyses. Argillic, argillic-phyllic, advanced argillic, silicic along with Cu, Fe, Pb, Zn, Co, Ni, Au and Ag are the most important decentralized natural resource contaminating agents that have formed extensive heavy/toxic metal haloes in this area. Diverse environmental pollution indices (e.g. geoaccumulation- Igeo, modified contamination degree- mCd and potential ecological risk- RI) show that the leve of environmental pollution risk of Pb is considerable and, as in different alteration zones, quaternary sediments are also very high. Soils highly contaminated with sulfur result in the high sulfide mineralization character of the alteration zones in Zakhur District. Calculations of the mass changes in argillic and silisic zones indicate enrichment by Cr, Ni, As, Pb and S and loss of Hg and Cd. Besides the positive correlation of heavy metals with each other, there are significant correlations between them and Mn and Al which may have occurred due to the adsorption processes by manganese, iron oxides and/or clay minerals.