Environment
Feridon Ghadimi; Amirhossein Solaimani
Abstract
Chogan region is located in the west of the Urmia-Dokhtar volcanic belt and northwest of the Markazi province in Komijan City. Copper mineralization has a vein type with a length of 260 meters and an average thickness of 4 meters. Mineralization was taken in a sheared silica vein. Eighty three samples ...
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Chogan region is located in the west of the Urmia-Dokhtar volcanic belt and northwest of the Markazi province in Komijan City. Copper mineralization has a vein type with a length of 260 meters and an average thickness of 4 meters. Mineralization was taken in a sheared silica vein. Eighty three samples were taken from the surface ground, in the trenches and it determined the concentration of 10 elements such as Fe, Al, Ca, Ba, S, Mn, As, Pb, Zn, and Cu. It was determined, that S, Ba, Mn, Fe, and Cu are secondary elements in the tuffs by the method of factor and cluster analysis. The constituent mineral such as barite and malachite are vein-shaped, but iron oxides such as hematite and goethite in the form of iron gossan. Geochemical, mineralogical, and geophysical (IP/RS) indices were investigated to separate copper oxide and copper sulfide zones. Sulfur and Ba were used in barite and excess S was chosen as sulfide index (Is). Chalcopyrite and metal factor were chosen as separating oxide and sulfide zones. By combining the geochemical and metal factor, it was approximated the apparent sulfide zone depth and confirmed with actual depth in borehole and error was less than 12%.
Environment
Feridon Ghadimi; Abolfazl Shafaei; Abdolmotaleb Hajati
Abstract
This work investigates the extraction of sodium sulfate (Na2SO4) from Mighan Playa in Arak, Iran, where 163 boreholes were drilled to depths of up to 20 m revealed a heterogeneous lithology dominated by Glauberite (Na2Ca(SO4)2) and Mirabilite (Na2SO4·10H2O) with average sodium sulfate concentrations ...
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This work investigates the extraction of sodium sulfate (Na2SO4) from Mighan Playa in Arak, Iran, where 163 boreholes were drilled to depths of up to 20 m revealed a heterogeneous lithology dominated by Glauberite (Na2Ca(SO4)2) and Mirabilite (Na2SO4·10H2O) with average sodium sulfate concentrations of 25% (ranging from 2–32% and peaking at 55% in localized southwestern areas). The playa’s surface is primarily clay-covered (94%) and interbedded with evaporitic facies including Gypsum, Halite, and carbonate minerals. Seasonal water inflows of 200–800 l/s from a wastewater treatment plant, together with 3.5 m-deep extraction pits and gravitational drainage, have resulted in stagnant ponds over 25% of the southern lake area and an annual reduction in surface area of 5–10%. Stratigraphic analysis further indicates pure Glauberite layers (0.5–1 m thick) at depths of 1,653–1,656 m, in contrast with thicker impure Glauberite-Mirabilite sequences (up to 9 m) present between 1,649–1,659 m. To mitigate these challenges, an integrated engineering approach is proposed that includes pumping seepage brine (with a moisture content of 40%) to solar evaporation pools, employing continuous dual-pump slurry systems for tailings management, and implementing hydraulic balancing through retaining walls and winter brine reserves—measures that enhance extraction efficiency by 30–42% in high-concentration zones. These adaptive mining practices, incorporating in-situ brine leaching and advanced wastewater treatment, are designed to meet 70% of Iran’s annual sodium sulfate demand from an 8 km² operational area while reducing environmental degradation.
M. Fooladi; F. Ghadimi; Seyed J. Sheikh Zakariaee; H. Rahimpour Bonab
Abstract
In this work, we determine the factors affecting soil erosion and its effect on dust formation around the Mineral Salts Company in Mighan playa of Arak. Seventy samples are randomly sampled from a depth of 10 cm above the ground around Mighan playa. Some factors involved (e.g. sample aggregation, lime, ...
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In this work, we determine the factors affecting soil erosion and its effect on dust formation around the Mineral Salts Company in Mighan playa of Arak. Seventy samples are randomly sampled from a depth of 10 cm above the ground around Mighan playa. Some factors involved (e.g. sample aggregation, lime, organic matter, pH, Na, K, Ca, and electrical conductivity) are determined and compared with the statistical parameters such as the correlation matrix and cluster analysis in order to determine the erosion rate in each sample based on the soil properties. The results obtained show that soil salinity, as a major factor in erosion, causes soil depletion and degradation in the area. Also a high amount of sand in the environment causes the soil texture instability. The factors such as the amount of gravel, organic matter, and K are the main erosion inhibiting factors, which have little effect on the majority of the samples. The organic matter content in most samples is less than 4%, and does not have much effect on erosion. The amount of clay in the samples is less than 10%, and has no effect on the adhesion of soil texture. The main factor affecting the erosion rate is EC and Na in the soil. The inhibitors such as gravel, organic matter, K, and clay amount in the samples can be considered as a protective or reducing factor in erosioning. Rising in the mentioned factors in the soil causes a lack of density and instability in the soil, and increases the rate of soil erosion. The results of this work show that addition of soil erosion increases the amount of fine-grained soil, and dust is a result of increased production. Also the presence of mineral salt in the area increases the production rate of dense soil, and as a result, rises the amount of dust produced in the area. Therefore, we need to stabilize mining soil, and prevent dust generation around the Mineral Salts Company.
F. Ghadimi; A. Hajati; A. Sabzian
Abstract
The Mighan playa/lake is characterized as a closed catchment. In the recent years, the rapid industrialization and urbanization has resulted in a pollution area in the city of Arak. In this work, we focus on six regions around the playa/lake to study the distribution of heavy metals in the waters and ...
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The Mighan playa/lake is characterized as a closed catchment. In the recent years, the rapid industrialization and urbanization has resulted in a pollution area in the city of Arak. In this work, we focus on six regions around the playa/lake to study the distribution of heavy metals in the waters and their contamination risk. A total of 32 water samples are analyzed to determine the contamination degree of heavy metals, i.e. Hg, As, Cd, Cr, Cu, Pb, and Zn. The heavy metal pollution index, heavy metal evaluation index, and degree of contamination are utilized to assess the pollution extent of these metals. The spatial distribution patterns reveal that the waters in different areas of playa/lake are in a good condition. The island, lake in playa, and the Wastewater Mineral Salts Company are most seriously polluted with Pb, being higher than the standard of drinking water quality limit. Water in the wastewater treatment plant is polluted with Hg and As. The correlation matrix, factor analysis, and cluster analysis are used to support the idea that Pb may be mainly derived from the atmospheric input, and As and Hg from the wastewater treatment plant, agricultural lands, and domestic waste. Many native and migratory birds live in the Mighan playa, which is exposed to heavy metals. Therefore, it is required to monitor heavy metals in the Arak playa and to manage the municipal, industrial, and agricultural activities around it and to reduce them.
