بررسي پتانسيل آلودگي در محدوده معدن مس مزرعه اهر و تعيين منشأ آن‌ها

Investigation of potential contamination in Mazraeh copper mine and determination of their origin

پژوهش حاضر به‌منظور بررسي منشأ احتمالي آلودگي حاصل از عناصر كمياب و تعيين ويژگي‌هاي هيدروشيميايي منابع آب موجود در محدوده معدن مس مزرعه اهر انجام شد. به‌منظور دستيابي به اهداف پژوهش در منطقه موردمطالعه، اقدام به نمونه‌برداري ماهانه از منابع آب منطقه گرديد. پارامترهاي اندازه‌گيري شده شامل pH، هدايت الكتريكي، عناصر اصلي، فرعي و كمياب بود. نتايج حاصل از تجزيه شيميايي عناصر، غلظت بيش‌ازحد مجاز شرب عناصر كادميم، سرب و كبالت را نشان داد و همچنين نمودارهاي پايپر و استيف وجود دو تيپ بيكربناته و سولفاته آب منطقه را نشان داد كه مطابق با سازندها و شرايط زمين‌شناسي منطقه بود. يافته‌هاي حاصل از آناليزهاي آماري چند متغيره تحليل عاملي نيز 4 گروه عاملي را در كيفيت منابع آب منطقه معدن مس مزرعه اهر مؤثر نشان دادند. عامل دوم و سوم زمين‌زاد و عامل اول و چهارم متأثر از هر دو عامل زمين‌زاد و انسان‌زاد است. به‌طور كل اكثريت عناصر كمياب موجود در منابع آبي متأثر از سازندها و اندركنش آب-سنگ است. براي دسته‌بندي داده‌هاي هيدروشيميايي از روش خوشه‌بندي مرتبه‌اي استفاده شد. ميزان EC⸲ سولفات و كلسيم در خوشه اول بسيار بيشتر از خوشه دوم بود كه نشان از انحلال كاني‌هاي سولفيدي منطقه است.

Investigation of Contamination Potential in the area of Ahar Mazareh Copper Mine and Determination of their Origin. Introduction Investigating the quality of water resources in an area is one of the most fundamental issues in the study of contamination. The term “trace elements” generally refers to elements that are present in the environment in small concentrations and can be hazardous at concentrations above the permitted standard of drinking. The origin of these elements can be geogenic or anthropogenic. The geogenic origin of these elements is the earth's crust, and the anthropogenic origin can also be due to industrial, agricultural, and mining activities. One of the strategic tasks in the field of water resources is to provide chemical information in a way that it can be visually reconstructed. Mazraeh mine is one of the copper mines in Iran that uses a lot of water daily to concentrate copper through flotation, which along with other contaminates is directed to the tailings dam, Therefore, it is necessary to study the affected factors to the hydrochemical evolution and quality of surface and groundwater resources and to investigate the relationship between elements and contaminates and its impact on the quality of water resources and most importantly the origin of these elements and their relationship with mining and tailings dams. In this study, Hydrochemical study of water resources in the study area has been done by plotting methods such as Piper and Stiff diagrams. Multivariate statistical methods such as factor and cluster analysis were used to evaluate the origin of the trace elements. Materials and Methods Mazraeh copper mine is located 5 km from Mazraeh, and 120 km from Tabriz. It is located in the north of East Azarbaijan. Geologically, the study area is part of the Alborz-Azarbaijan structural unit. The geological map of the study area shows that the oldest geological units in the study area belong to the Cretaceous. Mazraeh copper mine reserves are of the iron and copper skarn index type. In general, in this study, on average, about 16 water samples were collected monthly from surface and groundwater resources in the area of the Mazraeh copper mine; The samples include 8 water samples from piezometers in the area, 1 sample from tailings dam, 1 sample from overflow of the tailings dam, 1 sample from water well of the village near the mine, and 5 samples from springs. Discussion of Results The amount of electrical conductivity also varies between 254 and 1774 μS / cm. The amount of the concentrations of the major cations and anions in terms of the median are "potassium Conclusions Based on the results, the Piper and Stiff diagrams plotted for water, the water type was mainly divided into two groups of sulfate and bicarbonate; the resource of water in the area corresponds to the geological formations of the area. The results of chemical analysis of about 290 water samples showed that some trace elements such as cadmium, lead, and cobalt have more concentrations than the standard of drinking water. The results of factor analysis showed that 4-factor groups were effective in the quality of water resources in the Mazraeh copper mine area. The second and the third factors were geogenic and the first and the fourth factors were affected by both geogenic and anthropogenic factors. The majority of trace elements in water resources are affected by the impact of formations and water-rock interaction. In the clustering method, amount of EC, sulfate, and calcium in the first cluster is more than in the second one, which indicates the effect of dissolution of sulfide minerals such as pyrite and chalcopyrite in the area. The amount of zinc and iron in the second cluster is more than the first cluster.