GEOSCIENCES
Year:2015 | Volume:24 | Issue:95 (ENGINEERING & ENVIRONMENTAL GEOLOGY)|Papers Count:31

By fast growing of structures and need for aggregates materials, more quarry resources should be provided and rapid identification and exploration of these resources should be introduced. Because of the importance of engineering geology parameters in exploration of aggregate quarries sources, based to in-situ and laboratory studies in this research, the parameters and criteria were determined and the results are presented as a simple applicable criterion. For this purpose, first site investigation was carried out and then samples and specimens from different selected mines were taken. Laboratory tests were carried out in accordance with relevant standards, and finally concrete samples were prepared using these materials. The results of tests on aggregates and concrete have been analyzed, and parameters involved in the quality of the concrete were classified and presented as a criterion. According to accuracy and ease application of this criterion, it is applicable for selecting the materials with minimum experiments, the desirable mines identification and an estimate of the ultimate strength of concrete will be provided for the engineers. The criteria according to type and kinds of the samples, is applicable with a broad scope in different geographical areas.

Rock falls are the usual forms of slope instability in hill slopes. The high velocity and rapid occurrence are the main differences of rock fall and other rock instability. Therefore, the rock falls are among the most destructive mass movements and results in high loss of lives and heavy damage to the structures, roads, residential area, farms and etc. In this research, rock fall in rocky slopes of the Tepal Mountain in northwest of Shahrood city was investigated. For this, the large scale geological map of area (scale of 1:10000) was produced and joint studies in 12 sections performed. Then, the slope instability was analyzed by two methods of stereographic (using Dips 5.103 software) and analytical method (by Swedge 4.078 and rock fall 4.039 softwares). The results show that all of the slopes are stable in static conditions and become instable in dynamic state. In critical states of huge raining and earthquake intense instability will be occurred and the big problems could be created for the down area of slopes. Based on the results of analytical and using the Arc GIS 9.3 rock fall hazard zonation map was produced. In addition, by overlaying of landslide hazard map and land use map, the area affected by rock falls was distinguished. The results of this study show that Salamaty road, Mazar Shohaday Gomnam and its access road, some part of Azadi Park, the tourism hotel, some of the residential area down of the Salamaty road and some parts of the Abshar Park are located in the hazard zones.

Regarding to the destructive earthquakes that happened in the world and Iran, potential influence of surface geology on strong ground motion and the damages due to the earthquakes that named as site effect is well known. This study is a section of seismic microzonation of Shahreza city. In this study we further investigated the site effect by microtremor measurement and for analysis of microtremor data; H/V (Nakamura’s technique) was used. Accordingly, the microtremor measurement has been estimated for 64 sites of Shahreza city. Finally, the results are presented in different maps as natural period distribution of site, amplification factors and Vulnerability Index. The calculations revealed that the natural period is differing from 0.04 to 0.38 and the amplification factor differs from 1.21 to 6.88, too. The results showed a relatively acceptable connection with the morphology of the region. Thus, the natural period is decreased by moving toward the mountains around the city, whereas the natural period is increased by moving toward the center of plain. The results of this study as preliminary investigation can be used with detailed investigations in metropolitan planning for Expansion of City, estimation of seismic risks and crisis management due to an earthquake.

In cold regions, freeze-thaw cycles are one of the most important agents affecting on the mechanical properties of stones and consequently their durability. Uniaxial compressive strength, Brazilian tensile strength and P-Wave velocity are among important mechanical properties in assessing the durability of the stones used in cold regions. As regards of determination these properties during the freeze-thaw cycles experiment is very time consuming and cumbersome, statistical relationships can be used to estimate the mechanical properties. In this study, a multivariate statistical model is presented for 15 samples of travertine, which can estimate uniaxial compressive strength, Brazilian tensile strength and P-Wave velocity in each cycle of the freeze-thaw experiment. In this model, mechanical properties after freeze-thaw cycles were considered to be the dependent variable that dependent on the variables of the initial mechanical properties, water absorption and the number of freeze-thaw cycle. The statistical tests results and also data from other researchers show that model presented is reasonably accurate in estimating uniaxial compressive strength, Brazilian tensile strength, P-Wave velocity and consequently their durability of the travertines in each cycle of the freeze-thaw experiment.

Roads are of linear engineering projects passing various rock units and geological conditions, so it is necessary to engage the engineering geological studies along the way. The studies continue until the end of the construction and operation. In the route selection process, large volumes of data and different track conditions are facing. To perform this manually is time consuming and not accurate enough. This study examines the status of engineering geology freeway route Qazvin - Rasht in Roudbar discussed in this context, the factors affecting engineering geology route selection and construction of the freeway, using the Analytical Hierarchy Process (AHP) and Expert Choice software to give weight of these factors, according to their suitability for the construction of freeways, and then layers weighted overlay in GIS software and the final map has been prepared. The final map shows the quality of route engineering geological conditions, which is provided for both surface and subsurface (tunnels) with the least error. Since the procedure for engineering geological survey route is a new method, it requires further investigation and to test in other places in order to be much more modified and corrected. On the other hand, this model can be used for other engineering geological investigations due to high flexibility of this model.

In destructive earthquakes lots of break down in structures such as vital lifelines and buried pipelines also destruction of massive buildings have always been observed. These destructions can sometimes cause more serious injuries. The absorbed force and destruction caused by the earthquake in surface structures are proportional to their mass and inertia, so that with increasing acceleration, the amount of forces is higher. This is despite the fact that the behavior of buried structures actually influenced by the behavior of the surrounding soil and the mass of structure in comparison with their environmental soil is very small and negligible. Therefore, using the methods based on earthquake acceleration parameter can’t be sufficient in designing of such structures and existing of the speed spectrum designing along with the acceleration spectrum available in 2800 building code is also necessary, because the seismic design of such structures is based on the displacement response method. That is, first the displacement of the earth in location of buried structures using velocity response spectrum is calculated and the interaction between earth and underground structure is analyzed with quasi- static method. Velocity response spectrum for seismic designing of buried structures based on the maximum response of the earth surface layer due to the desired acceleration entering the bottom layer is obtained from a soil profile analytical model. In this study, we have tried to determine the curve of the velocity spectrum factor for soil type 1 and 2 according to the accelerograms data obtained from different earthquakes in Iran For this purpose, among the received accelerograms data from the Building and Housing Research Center, we selected 306 horizontal accelerograms of soil type I and 323 horizontal accelerogram of soil type 2. The normalized velocity spectrum of each accelerogram were calculated separately based on the maximum values of the velocity domain and acceleration. Accordingly, for each of these two types of soil we obtained two sets of normalized velocity response spectrum. Then, for each set, mid and 84% - design spectrum were determined. Finally, mathematical model of velocity spectrum factor curves was determined and presented in the formula for soil conditions of types 1 and 2 of Iran.

In order to study the crustal movements in Iran, establishment of several campaign GPS networks in 1998 seriously initiated geodynamical activities. After that in 2005, a network of ~120 permanent GPS stations named Iranian Permanent GPS Network (IPGN) has been installed to complete the campaign GPS networks already existing in Iran. Thanks to all campaign and continuous GPS sites, there are many geodetic velocity vectors indicating kinematic behavior of the crust at their positions. Now, the main question is about geodetic velocity for any other arbitrary station. Evidently, the best reliable solution is installing more GPS stations and recording satellite signals, which need considerable cost and time. Another solution, which could be an appropriate alternative, is applying some modern and smart estimation methods such as “Artificial Neural Networks (ANN)”. The main advantages of ANN method are capability learning of networks, parallel processing and computation flexibility. Based on 42 GPS velocity vectors existing in NW Iran, we estimated new velocity vectors for some arbitrary positions in study area by using two estimation methods: “Back Propagation Artificial Neural Networks (BPANN)” and “Collocation”. This estimation was run in 2 models including 2 different reference stations but the same check points. The results from model 1 (with fewer reference points) showed BPANN’s RMSE in E and N components is ±2 mm and ±3.5 mm respectively, which is less than Collocation’s RMSE. The results from model 2 (with more reference points) showed BPANN’s RMSE in E and N components increased to ±1 mm and ±1.5 mm respectively. Therefore, it seems BPANN method could be considered as a good alternative to estimate geodetic velocity field relative to other classical estimation methods.

The method of ground penetrating radar (GPR) has increasingly been used for investigation of surface and internal structures of glaciers within the last few decades. This geophysical method distinguishes different structures of glaciers considering the existence of electrical permittivity contrast between ice, air, sediment debris and water in the glaciers. In this research, the GPR acquired data using unshielded antenna with central frequency of 25 MHz along 3 lines in Alam kuh glacier, Kelardasht, Mazandaran, in June 2012, have been processed and interpreted. In order to remove the effect of low-frequency unwanted reflections overlain on high-frequency reflections from all GPR sections, we have used dewow filter. Moreover, we have used gain function for signal enhancement, especially in late times of the GPR data acquisition. Considering the coarse topography of the study area, we have also applied topography correction on the data, and then, the obtained results have been compared with the obtained results without topography correction to demonstrate the importance of topography correction on GPR data. Moraine materials, covered the surface of the area, are mainly fine-grained granite. The bed rock or basement in the area is also granite. The polarity representing ice-bed rock is clearly seen on the GPR profiles. Furthermore, the results of this research indicate that recognition of moderate and cold ice areas in the glacier, type of the glacier (Multi-thermal), holes and topography of the glacier basement has successfully been possible using only the GPR method. The electrical resistive nature of the glacier has caused large depth of penetration of GPR waves in this research work.

In this research, the areas for prospecting porphyry copper deposits have been introduced using airborne geophysical data (magnetic and radiometric). Magnetic anomaly boundaries have been detected using the reduction to the pole (RTP), upward continuation (with different heights), horizontal derivative (HD) and tilt angle filters to estimate approximate depth of magnetic structures. In addition, the felsic intrusives and potassic alteration zones have been determined using radiometric data and the obtained ternary map. Finally, due to genetic model of porphyry copper deposits and effective factors on mineralization and integration magnetic and radiometric data results, the Chahargonbad region has been categorized according to the priority of the porphyry copper mineralization. The most favorable areas are located in north, center and east of study area.

The study area is located at 42 km NE of Qorveh city, in Kordestan Province and in the Metamorphic– Magmatic Sanandaj-Sirjan Zone. There are other important gold mines such as the Zarshouran and Aghdarreh mines in this zone. The most important alterations of the region are sericitic (phyllic), argillic, silicification and propylitic respectively. Therefore, in this research, the phyllic and argillic alterations were the main purpose and by using different techniques of images processing of satellite images such as: False Color Composition, Band Ratio, Principal Component analysis, Crosta and finally by Spectral Angle Mapper methods iron oxides and development of alterations have been recognized. For accuracy between field evidences and results of software processing, X-Ray Diffraction analysis were used for controlling and recognizing the index minerals of each zone. Then, the comparison between standard and the study area curves were done to confirm the obtaining results. Finally, this method was effective in recognizing and mapping of the hydrothermal alterations.

In the 11th August 2012 two Earthquakes trembled Azarbayjan that their scales were 6 Mw and 6.2 Mw. The locking depth of these two earthquakes is about 10 km, the epicenter of the first one is 38.55 N and 46.87 E, and the second one is 38.87 N and 46.87 E. In this research displacement of the earth crust during trembling on these stations was determined by using permanent GPS stations in Ahar Earthquake 2012. The cosiesmic offset due to the Ahar earthquake has been studied using permanent GPS Network of Azarbayjan (a sub network of Iranian permanent GPS Network). Here, we explore these issues using data processing and times series analysis of the GPS sites. We found 0.5 to 2 cm offset that the GPS site (near and far) showed from the main rapture due to earthquake.

The 1:100000 sheet of Ardestan is located in the south part of 1:250000 quadrangle of Kashan at 52o to 52o, 30 E and 33º to 33o, 30 N in the north west of Isfahan province and Orumieh-Dokhtarvolcanic belt.Most of the rock units’ of Ardestanregion include medium to basic volcanic and pyroclastic rocks, which are related to middle-upper Eocene volcanism phase. Intrusive rocks of this region have low-acidic to acidic combinations and belong to the shallow magmatism phase of Oligocene-Oligo Miocene and sub-volcanic activities of Pliocene. These intrusive rocks cause hydrothermal alteration and then mineralization of elements such as Cu, Mo, Au, Pb, Zn, and Fe. In this thesis, by employing the existing geological maps, systematic geochemical explorations, and known mineral indices together withthe derived information from processing of the existing airborne geophysics and satellite data (e.g. faults, hydrothermal alterations, total magnetic intensity and rock units), a number of different databases were formed. Then, by using the new weighted score method of analytic hierarchy process (AHP), these databases (also known as layers) are weighed based on the predicted genetic model of the region. These weighed layers are then modeled in the GIS system by using the index overlay method. Based on the achieved results from this study, promising area maps for Epithermal Gold is prepared. According to our field observations, sampling and laboratory analyses of the promising areas, 5areas with first priority are considered to have economical potentials and are introduced for the next phases of explorations.

Gandom Beryan or Burned Sand region is located in the Lut Desert, NW of Kerman. This region has always been under consideration due to its high temperature. In this study, by utilizing thermal Remote Sensing studies, ENVI software, and thermal images ETM+ (imaging time 10 am on Wednesday 7 October 2011) the surface temperature of Gandom Beryan was measured. Non-uniform distribution of basaltic rocks, erosion, and fracturing of rocks in Gandom Beryan has caused the calculated surface temperature in the southern part of the Gandom Beryan, which has been covered with dark basaltic rocks, shows reflections intensity more than the northern part of the study area. On the other hand, the photolineament index factor shows that the zones with greater fracture intensity than the other side have less temperature. The existence of mountains in all directions of the Lut desert (north, south, east, and west) have limited the penetration of sea moisture especially from the Indian Ocean, and this problem causes the increasing of drought, sunshine, and decreasing of cloud in this region. In general, desert location, including latitude and low altitude are factors that cause the high temperature of Basaltic messa besides the special surface absorption of basalt. Respect to daily and monthly corrections, the final temperature is calculated as the estimated maximum temperature, which is at least 76° C for Basaltic messa in Gandom Beryan and based on the surveys, this region can be considered as one of the Earth thermal poles.

Rusted bottles and ragged car tires are good examples of modern waste materials, which can cause significant environmental concerns. Despite all environmental issues of these materials they could be used as a reinforcement material in weak soils. This strategy not only reduces the volume of waste materials but also can make them valuable. The results of laboratory tests have shown that using PET crushed particles can improve the engineering properties of sandy soils while for rubber fibers these changes are not as positive as PET particles. In fact using rubber fibers has damaged some of the engineering characteristics of the sandy soils.

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.

The Karstic Asmari & Jahrom Formations extensively outcrop in the Darab city region. The current Darab landfill site is located on sandy gravel alluvium, a few meters above the karstic Asmari Formation. The objective of this study was to investigate the effects of the landfill on groundwater quality. Ten karstic and alluvial exploitation wells and downstream of the landfill site were sampled to measure the concentrations of major ions, nitrates, heavy metals, trace elements, total coliform and fecal coliform. The major ions and nitrate concentrations are below the EPA Maximum Contaminant Levels (MCL). The fecal coliform exceeds the EPA MCL in most of the wells. There is no contaminant source to justify the high levels of fecal coliform in the exploitation wells. Fecal coliform is naturally present in the soil based on recent researches. The concentrations of Sb and Se are more than the EPA and WHO MCL in some of the wells. The source of these contaminants is not the Darab landfill, because no general flow direction and concentration trends are observed from the landsite towards the contaminated wells. In addition, there is no anthropogenic source of these elements in the study area. The sources of Sb and Se are most probably geogenic from limestone and shale. The volume of aquifer dynamic storage has been significantly reduced due to overexploitation and drought. Therefore, Sb and Se were dissolved in ever-decreasing volumes of water, and consequently, their concentrations increased.

The investigation on toxic elements in sediments around the Chahar Gonbad copper-gold mine indicates sediments with various sources of pollution. In order to investigate the source and chemical fractionation of toxic elements 38 sediment samples were collected from 0 to 5 cm depth of river, alluvium and dam sediments randomly. The average values of elements in sediments are: 0.09 ppm Ag, 17.82 ppm As, 0.48 ppm Bi, 0.22 ppm Cd, 17.58 ppm Co, 91.49 ppm Cu, 43161.33 ppm Fe, 1152.83 ppm Mn, 0.97 ppm Mo, 41.5 ppm Ni, 10.82 ppm Pb, 484 ppm S, 1.3 ppm Sb, 0.13 ppm Se, 1.05 ppm Sn, 3067.67 ppm Ti, 0.35 ppm Tl, 126.5 ppm V and 90.82 ppm Zn, respectively. The average values for waste dam sediments include 0.22 ppm Ag, 28.37 ppm As, 13.14 ppm Bi, 0.26 ppm Cd, 51.88 ppm Co, 1981.4 ppm Cu, 81677.33 ppm Fe, 2165.13 ppm Mn, 72.86 ppm Mo, 80.67 ppm Ni, 191.38 ppm Pb, 5593.17 ppm S, 47.75 ppm Sb, 0.66 ppm Se, 1.77 ppm Sn, 2136.83 ppm Ti, 0.43 ppm Tl, 80.75 ppm V and 989.94 ppm Zn. The obtained results were evaluated by using of multivariation statistical method including correlation coefficient, principal component analysis (PCA), and cluster analysis (CA). By using a multivariation statistical method it becomes obvious that the sediments can be divided into four different categories. The first category of these sediments are derived from mining activity, which in the first component of the PCA analysis are related to Ag, As, Cd, Co, Cu, Fe, Mo, Pb, Sb, Se, Sn, Tl and Zn. The second category of sediments are not affected by mineralization and in the second component of PCA analysis are indicated by Al, Sc, Sr, V, Ta, Ti. The third category is of natural sediments, on which, rock source and mineralization had an influence, thus include the third component of PCA analysis and are indicated by Bi, Mn, and S. The forth category of sediments include toxic elements such as Cr and Ni that either are derived from weathering of sulfides or probably from ophiolitic rocks.

The Neka River is located at 21km in east of Sari, center city of the Mazanderan province, north of Iran. 51 stream sediment samples were collected from 4 sample sites. The samples were digested by HF+HClO4+HNO3 and analyzed by AAS in laboratory of Geological Survey of Iran. The results of analysis show that the enrichment ratio and Geo-accumulation index are too high for Ag, Cd and Sn in the whole sediments of the Neka River. Zn shows very high enrichment in the sites of Boz Mil and Lajan Lateh Sofla sample sites and Pb shows very high enrichment in the site of Boz Mil. Degrees of Geo-accumulation Index are very high for Ag-Cd in the 4 sites but for Zn are high to medium and for other elements are medium. In the Neka Choob and Mola Khil sample sites, the Co and Ag are too high because of anthropogenic contamination and Fe and Ni are low relatively. In the Boz Mil and Lajan Lateh Sofla sample sites, the Pb and Ag are too high because of anthropogenic contamination and V, Ni, Cu and Zn are low relatively. Coal mining and coal deposition in the upper part of the Neka River, urban and wood industry sewage are the main sources of the pollution.

Considerable quantities of wastes are generated in drilling operation contain various components such as heavy metals and hydrocarbons. These wastes are discharged in pits or the sea, which their geochemical composition should be investigated for waste management. In this study, sampling of heavy water based mud additives; different lithology of the Gachsaran formation and soils around location was performed. After preparation, metal concentrations in samples were determined by ICP-MS method. The results showed that the concentration of metals such as lead, copper, arsenic, zinc, molybdenum, antimony, mercury, and strontium in the Gachsaran wastes are more than standards and soils of the region. In addition, the calculated correlation coefficients between elements in wastes showed that possible mineral phases as impurities associated with barite. The environmental assessments also suggested that these wastes are extremely polluted for Ag, Sb, As, Cu, Pb. Using pure barite could reduce the amounts of the heavy metals.

One of the most basic problems in the exploration and extraction of the ornamental stones quarries is the recognition and modeling of the discontinuities. Generally, in the most of the ornamental stones quarries, analysis of the discontinuities is not considered. This study is dealt with the discontinuities analysis in the limestone outcrops. The Kerman ornamental stones quarries are located at the Cretaceous limestone. Geological study shows a development of lineaments due to effect of two faults systems. Normal faults have a dominated feature and cause an intensive fracturing in the ornamental stones quarries. In order to analysis of the lineaments, ETM+ image was filtered by use of ENVI software in the orientations of 45, 90 and 315 degree and then with use of ArcMap software, characteristics of discontinuities (e.g. orientation, length, intersection and number of lineaments) have identified in GIS, and map of lineaments density was prepared for each outcrop. The comparison of lineaments characteristic in GIS and field observation reveals a high coincidence between two method. The results of this study show an intensive fracturing in the outcrops. It is concluded that most of outcrops show a high risk for extraction.

Frequency Domain Electromagnetic surveys are being used for various applications like mineral and water exploration, environmental hazards and buried human-made materials because of its resolution and fast acquisition for low depth targets. Resistivity and its depth for each frequency could be calculated in a simpler approach and shorter time than Iterative Inversion Method, Called Straight or Fast Inversion Methods, by assuming earth as a homogeneous half space. Barika’s Anomaly situated in Alut Geology 1:100,000 sheets in west Azerbaijan is studied in order to prospect gold- lead mineralization which has been detected in systematic geochemical and litho-geochemical surveys. In this paper we studied different Fast Inversion algorithms for synthetic data then applied the best method for real data. Resistivity distribution for each frequency produced and appropriate interpretation according to geology acquired. The results showed that there is a good correlation between low resistivity and shear zones. Also geology map can be modified with higher frequency resistivity.

The purpose of this paper is to investigate the performance of photogrammetric method for determining the orientation of the discontinuities. The application of photogrammetric method for surveying discontinuities is applied as useful method. In the scanline method because of topographic constraints, disontinuities in the top part of the bench can not be measured. In addition, in this method when the angle between the discontinuities and scanline approaches to 90 degrees the discontinuities have more chance to sample. The discontinuities in a rock outcrop in the Golgohar mine No. 1 in Sirjan were sampled using the two described methods. In the scanline method, 42 discontinuities and in the photogrametric method, 258 discontinuities were sampled. In the scanline method, two joint sets and in the photogrametric method three joint sets were recognized. The two joint sets J1 and J2 are similar in the two methods showing a small difference. However, the joint set J3, which is the most critical joint set in the view of slope stability, was only sampled by the photogrametric method. Since the photogrammetric method uses many points in the plane of discontinuity, it is more precise for determining the mean orientation of discontinuities.

With respect to the concentration of population, agricultural activities and industrial manufactures in Tabriz Plain area, vulnerability assessment of the plain aquifer is very useful for development, management, decision making for land use and preventing groundwater contamination. In this research, vulnerability of the Tabriz plain complex aquifer to contamination was considered by DRASTIC model in GIS media and different fuzzy logic methods adapted to optimize the model. The DRASTIC model uses seven environmental parameters effective on assessment of aquifers vulnerability such as Depth to groundwater level, net Recharge, Aquifer media, Soil media, Topography, Impact of vadose zone, and hydraulic Conductivity, which created as seven layers in ArcGIS media and weighted, rated and compiled, finally groundwater contamination vulnerability map was prepared and the DRASTIC index for the study area calculated between 40 to 126. The vulnerability map created by DRASTIC is compared to nitrate data and the results indicated a relative correlation between the nitrate level and vulnerability index. The Sugeno, Mamdani and Larsen fuzzy logic methods were adapted for optimizing the weights of the DRASTIC parameters. For this purpose, the DRASTIC parameters as input data and the vulnerability index as output data were defined for fuzzy models and nitrate concentration data were divided in two categories for training and test steps. The output of model in training step was corrected by related nitrate concentration, and after model training, the output of model in test step was verified by nitrate concentration. The results obtained from different fuzzy models show that the Sugeno fuzzy logic model is an applicable and useful method for optimizing DRASTIC model. According to the final model results, the eastern part of the area, inside the Tabriz city limits, has the maximum potential rate for contamination.

In the last few years, saline water intrusion in the Urmia aquifer has deteriorated groundwater quality. As a result of irremediable environmental impacts and deterioration of aquifer conditions, study on groundwater vulnerability due to saline water intrusion is very serious. This study focuses on the application of the new method, GALDIT, for the assessment of aquifer vulnerability due to saline water intrusion in the Urmia Lake. The computing of the GALDIT index is based on six parameters: Groundwater occurrence (G), Aquifer hydraulic conductivity (A), High groundwater Level above sea level (L), Distance from shore (D), Impact of existing amplitude and extensive of saline water intrusion (I), and Thickness of aquifer (T). The results of this study showed GALDIT indices were very high, high, moderate, and low in the northeast, southeast, north, and low in east of the aquifer, respectively. The GALDIT approach assists to managers for evaluation of aquifer conditions.

Natural fractures analysis as a main controlling factor in fluid currents is very important in the reservoir characterization. This matter was studied using thin sections, cores, and FMI and velocity deviation logs in one of the fields in the southwestern of Iran. FMI initial data, which were input to Geoframe software, processed and interpreted. Velocity deviation logs and secondary porosity were also measured and compared. The results indicated that stylolites, pores, open and filled microfractures in the reservoir are present. The relative density of open fractures decreased to depth while filled fractures increased. The fractures are mainly longitudinal and latitudinal types with high angles to bedding surface. The main porosity system of the reservoir is inter particle and fractures types. According to the presence of oil staining in thin sections, it is revealed that the fractures are suitable conduits to transferring the fluid.

Clay minerals reduce the reservoir quality in different ways. They may cause mechanical problems in drilling and lead to petrophysical misinterpretations.Therefore, Clay typing is necessary for upstream petroleum exploration and production industry. In this paper, type, amount and distribution patterns of different clay minerals in 76 core samples from two wells one of witch is producing and the other is non - producing in the Shurijeh Formation, aging early Cretaceous, were identified by six different instrumental analytical methods such as X-Ray diffraction (XRD), X- Ray fluorescence, thin section studies, thermal analysis (DTA-TGA), scanning electron microscopy (SEM) and measuring the cation exchange capacity (CEC). The results proved that the dominant clay minerals are illite, magnesium rich chlorite and kaolinite. The minor clays are glauconite (in the both wells), montmorillonite (in producing well) and mixed layers of illite-montmorillonite and chlorite-montmorillonite types. The average amount of each clay minerals in nonproducing well is more than producing one. Then clay minerals were classified on the percentage basis into five classes (less than 10%, 10-15%, 15-20%, 20-25% and more than 25%). According to quantity of samples in each class, the producing and non-producing wells were recognized as clean and shaly sand respectively. An increase in glauconite and Illite amounts and also an increase in illite and chlorite layers of mixed-layered clays with increasing burial depth and temperature is an obvious sign of burial diagenesis in this formation. The best correlation was observed between percentages of clay minerals and iron, aluminum, potassium and magnesium.The clay minerals in the Shurijeh Formation are diagenetic alteration of rock fragments, plagioclase and alkali feldspar in origin and in some cases they originate from outside with layered distribution. Distribution pattern of the autogenic clays are pore filling, pore coating and pore bridging, which cause the porosity and permeability reduction in this formation.

Copper oxide ores are usually leached in sulphuric acid solution. However, it has severe adverse impact on the environment. In this study, bioleaching and leaching by citric acid, as environmentally friendly methods, are investigated. The experiments were carried out on a copper oxide ore sample containing copper content of 3.4%. This sample does not contain any energy source to grow the conventional bioleaching microorganisms (like Thiobacillus ferrooxidans and Thiobacillus thiooxidans). This sample was leached by a heterotrophic bacterium, Pseudomonas aeruginosa. This bacterium produces organic acids in selected culture medium that operate as leaching agents. Leaching is investigated by citric acid, as an organic acid produced by this microorganism. The optimum bioleaching conditions were found as: lucose percentage of 6, bioleaching time 8 days and solid/liquid ratio 1:80 and optimum leaching conditions as: particle size range105-150μm, acid concentration of 0.2 M, 30 min dissolution time, solid/liquid ratio of 1:20 g/mL and temperature of 40oC. Under optimum bioleaching conditions 53 percent of copper was extracted and copper extraction under optimum leaching conditions was 92 percent.