نشریه زمین شناسی محیط زیست
پیاپی 45 (زمستان 1397)

Aquifer vulnerability assessment is very important for developing, management, making land use decisions, monitoring of groundwater resources quality and prevent groundwater contamination. In this research, vulnerability of Kahriz plain aquifer was evaluated by DRASTIC model and Geographic Information System (GIS). The model combines seven hydrological factors affecting groundwater contamination. These factors include: depth of groundwater level, aquifer net recharge, aquifer media, soil media, topography, Unsaturated Zone and hydraulic conductivity of the aquifer. Based on overlapping of resultant map vulnerability zoning map of the aquifer was prepared. Two main vulnerable zones including low and moderate vulnerable zone were determined. Area of moderate and low vulnerable zones are about 78 and 22 percent, respectively. Model validation was performed using the dispersion of nitrate concentration in the aquifer. Almost all areas with high nitrate were in the moderate vulnerable range.

Electronic and electrical wastes are special types of wastes whose main components include capacitors, transistors, ICs, electronic circuits, cathode and anode components, and have toxicity, pathogenicity and stability in the environment and even in the corpuscles, corrosive installations and Equipment and the like. Accordingly, the purpose of this study is to investigate and identify the effective factors in the liberation of these metals and especially the cadmium element in the surrounding environment. To investigate this, the effect of different factors such as temperature, pH, HMC and time on the release of cadmium from these wastes to soil environments has been studied. For this purpose, the selected parts were analyzed and examined. The results indicate that in the soil environment, the level of cadmium penetration in very acidic and very alkaline pH increases the amount of release. Also, in the soil environment, the increase in temperature increases the penetration of the cadmium element in the environment, and the effect of the contact time parameter is also proportional to the pH variation.

Mashhad plain in a special structural position and Influenced by the performance of a series of active faults in the northern margin of the Binaloud Mountain Range, The southern margin of the Kopet Dagh Mountain Range and the Quchan Eating Zone is located to the west. The activity of these faults has formed the stepping morphology of lowland rock. Also active faults in the thick Quaternary period and The expansion of alluvial sediments has a high potential for discharge. Chaheshk fault as a subsidiary of Shandiz fault zone in central part of Mashhad plain, It plays an important role in controlling the hydraulic behavior of the groundwater resources of this plain. This fault is based on the integration of geoelectric profiles and The results of machine excavations are first identified in this study.Wells drilled to the north of Chahshak fault with good discharge Often at depths of more than 250 meters, they have been impacted by clayey rocks and Neogene conglomerates. But wells drilled south of the fault with very low discharge and Or no discharge generally at a depth of 100 to 140 meters They have been struck by metamorphic rocks. The uplift of the rock in the south of the Chahshak Fault causes The stepping morphology has been followed by metamorphic rocks in the southern part of Mashhad plain. This metamorphic uplift as a positive flower-like building, Under the influence of a straight-strike strike-slip faulting system, it was created by a trance-tension mechanism.

The present research is conducted to study some heavy metals pollutants in Karaj River (the most famous river located in Islamshahr) including soluble oxygen, pH, TDS, EC, salinity; in addition, concentration of heavy metals including Ni, Cr, Cd, Zn, Pb, Cu, and As was also analyzed in water samples.To determine and examine the parameters, sampling steps were carried out at 5 stations along the River in February excluding other stations due to lack of water. Research data were analyzed using Pearson correlation coefficient test through SPSS. pH mean level 5555 in surface water samples indicates alkaline nature of water samples. High water conductivity of Karaj River results from agricultural and industrial activities. High TDS is related to water nitrate frequency. The descending trend of water sample main cations mean concentration is as follows: Magnesium> Calcium> Sodium> Chlorine. In Pier chart, water anions are of sulfate-type in the carbonate and bicarbonate facies; and water type in cations is of sodium- potassium situated in Manizic and Calcic facies. According to the results of correlation coefficients between nickel metal elements with chrome, copper with zinc, as well as chrome with zinc, the common origin of earth-born and lithogenic (human activities) is probably supplied in the River water. Furthermore, sulfate anions and some metal elements showed a positive correlation; in addition, chlorine ion also explains elements transportation at the sulfide phase.

Factors such as atmospheric precipitation reduction, inefficient agricultural methods, the threat of water resources from pollutants, etc. have all resulted in water supply issue confronting two challenges of quality and quantity in relation with aquifers. Similarly, in Malard county, underground water aquifers are the primary source of water supply. The information of physiochemical parameters of water samples of 9 water wells in Malard County during two drought and wet periods in the year 1396 have been collected. The objective of this study is the qualitative modeling of underground water and the calculation of GWQI index in the GIS system, and comparison. The findings showed that the quality of underground water from east to west, and from northeast to southwest confronts increment in physicochemical parameters because of the situation of the wells' depth, underground water scarcity, the decrease of earth self-purification, and bedrock lift as geological and hydrological factors as well as human factors entering the aquifers. This issue is more serious in Dehak Qeshlaq and Sharifabad counties. Considering the appropriate self-purification condition in Khoshnam County, this area can be introduced as a safe region. Moreover, a meaningful relation has been obtained between the outcomes resulted from GIS and GWQI.

Soil erosion is one of the major environmental concerns of the present century. This issue has become a major problem to the environment and natural resources, so that statistics indicate that soil erosion in Iran is several times more than global average. This research was carried out with to investigate the factors affecting the Varak area erosion and its risk zonation using the EPM method. For this purpose, field visits and satellite images studying were used to investigate the erosion. Then, the information layers of the area including average slope, soil and rock susceptibility to erosion, land use and observational erosion were prepared, and information layers were weighted and the erosion risk susceptibility map was prepared. In addition, the results from the risk zonation of the region show that 6.3, 55.2, 26, 3.1 and 9.4 percent of the region are at the erosion risk classes of very low, low, moderate, severe, and very severe, respectively. Based on the zoning, the focus of the erosion-sensitive areas are in the southwest, northwest, and a part of the north of the region, which is consistent with the fossilized and fractured parts of the Asmari lime, which has a higher slope. Considering the field observations, investigating the precision measurement of the method used to prepare the potential erosion risk map of Varak watershed indicates that the EPM method has a fairly high precision.

Karghan Area is located in East Azarbaijan province, southeast of Tabriz and northwest of Bostanabad city. Based on the division of the structural zones of Iran, it is part of the Alborz-Azarbaijan zone. The most important geological units in the studied area are shale, marl and limestone (Cretaceous), Sahand volcanic products of the age of Pliocene-Pliocoscene, Granitic intrusive, Gabrodiorite and Monzogranite, old terraces and Quaternary sediments. Regarding the spread of the area, 29 geochemical stream sediment samples and 29 heavy mineral samples were taken from the places. The anomalies of arsenic, barium, copper, lead and zinc in the region are represented by their statistical distribution type. The most important heavy minerals with lithological origin were zircon, amphibole and pyroxene. Heavy minerals of pyrite, magnetite and hematite are attributed to the mineralization holes. Heavy mineral studies indicate occurrence of malachite-copper mineralization in the region. Considering the observed anomalies in the stream sediments and heavy minerals, it is recommended detail exploration in the area