https://hydro.tabrizu.ac.ir/ Hydrogeology en daily 1 Sat, 23 Aug 2025 00:00:00 +0330 Sat, 23 Aug 2025 00:00:00 +0330 https://hydro.tabrizu.ac.ir/article_20144.html Following the impoundment of the Zemkan Dam, signs of water leakage were observed in the bay area within the reservoir, located on the northern side of the dam. This leakage manifested downstream as new springs, and previously existing small springs in the region became more water-rich, with some turning sulfuric, indicating the discharge of seepage water from the dam through these sources. Upon observing the leakage, dam impoundment was halted at an elevation of 1527 meters. To identify the leakage pathways and flow routes, as well as to understand the flow regime (diffuse or conduit flow) and the extent of karst development, a tracer test was conducted on the left abutment. In this operation, 10 kg of fluorescent dye (Uranine) was injected into the Tinj injection borehole, located at the normal water level above the area where water discharge sounds had previously been heard and a sinkhole had subsequently formed. The tracer was detected in several boreholes (T1, T2, T3, and T5) and in downstream springs (leakage springs 1 to 18 on the left flank and seven springs on the right bank of the river), as well as in Nazari Spring. The tracer velocity indicated conduit-type (undeveloped) flow in this region. A sealing measure was proposed to prevent further water leakage. The optimal option for sealing involves constructing a grout curtain from the crest of the limestone in the Tale Zang Formation at the head of the northern bay of the dam to the Tale Zang Formation within the valley. https://hydro.tabrizu.ac.ir/article_20897.html The Dargaz plain, located north of the Hezar-Masjed Mountains along Iran’s northern border with Turkmenistan, is the only major plain in this region. Due to the significance of the Dargaz aquifer in meeting region's water demands, the strong dependence of local livelihoods on groundwater, and the area’s strategic importance in terms of passive defense, an accurate knowledge of the aquifer system is essential. To identify the factors controlling groundwater quality, the dominant hydrogeochemical processes, and the evolutionary trend of groundwater chemistry, 45 water samples were collected from various sources and the results of the chemical analysis of the samples were examined using various hydrogeochemical techniques. Furthermore, to understand the stratification, subsurface geological structures of the aquifer, changes in thickness and lateral continuity of the layers, and the interconnection between alluvial and karst aquifers, lithological cross-sections in different directions of the plain and 3D models of the aquifer were obtained from the interpretation of geophysical data and 83 well logs. The results indicate that groundwater in the Dargaz aquifer evolves along the flow path from recharge zones in the northwest toward discharge areas in the southeast and east. Water–rock interaction, accompanied to a lesser extent by evaporation, is the main processes controlling groundwater chemistry. The hydrochemical facies change from carbonate type-reflecting recharge from the Tirgan formation-to sodium–calcium sulfate type, influenced by the evaporitic minerals of the Sarcheshmeh, Pestehligh, Chehel-Kaman, and Neogene formations. Lithological cross-sections and 3D models reveal considerable variation in alluvial thickness across the aquifer. In the southern aquifer, thick clay deposits, limited recharge, and the absence of major springs near the Allah-Akbar heights restrict hydraulic connectivity between alluvial and karstic aquifers, which is observed only in the southeastern areas near Chapeshlu and Parkand. However, in the northern aquifer at the beginning of the Darongar river, there is a possibility of alluvial aquifer feeding from the limestone heights of the Tirgan formation (from the Shamkhal karst valley). https://hydro.tabrizu.ac.ir/article_20999.html The present study investigates the effect of the slope of the Unconfined aquifer bed on groundwater level changes due to precipitation. For this purpose, a schematic design of the problem along with the relevant parameters was modeled in the case where the flow is in the direction of the bed slope in two cases with and without precipitation using the PMWIN MODFLOW software. After validating the numerical modeling results, a parametric study was conducted to investigate the effect of the bed slope, precipitation intensity, and soil hydraulic conductivity coefficient during precipitation on changes in the water level of the free aquifer. The results showed that the effect of the bed slope on the groundwater level is more obvious in heavier precipitation and that the effect of the slope on changes in the groundwater level profile is reduced by reducing the precipitation intensity. The analysis of the different hydraulic conductivity coefficients in the precipitation state at all slopes showed good agreement with each other, which indicates that the ratio of precipitation intensity to hydraulic conductivity coefficient (R/K) is dimensionless. The results indicate that the water level profile at all slopes follows a cubic equation. In the present study, relations were presented for the coefficients of this equation, which ultimately allow the groundwater level to be determined due to precipitation in a situation where the flow is in the direction of the bed slope. https://hydro.tabrizu.ac.ir/article_21229.html The proper management and planning for the sustainable exploitation of groundwater resources is essential due to the limitation of surface water resources and groundwater overexploitation in the dry region. Groundwater simulation using mathematical models allows the aquifer behavior to be investigated in response to different hydrological, climatic, and management conditions. Therefore, this study was conducted with the aim of calibration, sensitivity analysis, validation, and optimization of the saturated permeability and specific yield coefficients of the Kohourestan aquifer, located in the west of Hormozgan province, using the popular hydrological model MODFLOW under the GMS user interface. The difference between the measured and simulated groundwater levels in the model calibration stages was evaluated using the root mean square error (RMSE) criterion. The RMSE values in the calibration steady state, unsteady state calibration, and validation were calculated by the model to be 0.093, 1.03, and 0.998, respectively, which indicates the appropriate accuracy of the model. The results of model calibration in two steady and unsteady states showed that the northwestern areas of the aquifer have the highest values ​​of the permeability coefficient, which vary from 25 to 35 m/day. However, in the southeastern areas, the permeability coefficient is sharply reduced. The accumulation of coarse-grained and fine-grained sediments has led to a significant increase and decrease in the permeability coefficient in the upstream and downstream of the aquifer. https://hydro.tabrizu.ac.ir/article_21639.html Groundwater resources, as essential sources for drinking water and agriculture, are vulnerable to sand production, which reduces well efficiency and damages equipment. This study investigates and optimizes gravel pack design to control sand production in production wells in southern Urmia, Iran. Geological well logs were analyzed using LogPlot to identify sand-prone layers and dominant grain sizes in each well. Critical flow discharge was calculated based on Reynolds number and Shields criterion and compared with actual pumping rates to determine high-risk wells. Gravel pack design considered the physical and hydrodynamic properties of the aquifer and was evaluated through CFD–DEM numerical simulations. Four gravel pack types were designed for coarse (14.5–18 mm), medium (5.2–7.5 mm), fine (1–4.3 mm), and very fine sand (0.65–1.1 mm and 1.2–1.5 mm, dual grading), and their performance was simulated. Results indicated that selecting appropriate grain sizes and implementing a graded gravel arrangement enhances particle stability and prevents sand migration into the well. Optimized gravel packs effectively control fluid flow and mitigate sand production, thereby increasing well lifespan and water production efficiency. This study demonstrates the importance of integrating geological data, hydrodynamic analysis, and numerical simulations for sustainable groundwater well design, providing practical guidelines for selecting gravel pack size and configuration according to aquifer properties. https://hydro.tabrizu.ac.ir/article_21640.html Groundwater is a valuable resource for supplying water for various uses in most regions, especially arid and semi-arid regions of Iran, so continuous monitoring of groundwater quality is essential. In this study, temporal changes in groundwater quality in the Shahrekord Plain over the past 20 years were investigated. For this purpose, groundwater quality parameters measured in 11 wells in the Shahrekord Plain during the statistical period 2001-2021 were used. The trend of changes was examined using the nonparametric modified Mann-Kendall test and by removing the complete autocorrelation structure. The results showed that groundwater quality in the western and central regions of the Shahrekord Plain has been slightly decreasing in recent years and most variables did not have a significant trend. In the eastern and southern regions of the plain, the Na and SAR variables have had a significant decreasing trend. Also, in the northern and southern regions of the plain, the TH variable has had a significant decreasing trend. However, the trend of this variable in the Abdullah well in the center of the plain has been increasing at a significant level of 5%, which is related to the feeding of the plain with urban wastewater in this location. The results of this study indicate the importance of long-term monitoring of groundwater quality in the central region of the Shahrekord plain https://hydro.tabrizu.ac.ir/article_18021.html Magnetic separation is widely used to remove contaminants due to its high separation speed and efficiency. The combination of magnetic nanoparticles with other adsorbents not only does not affect their magnetic properties but also leads to the formation of adsorbents that improve the treatment process. In this study, the effectiveness of multi-walled carbon nanotubes magnetized with iron oxide (Fe3O4 (magnetic nanoparticles to remove the heavy metal arsenic from aqueous solutions. The synthesis of Fe3O4-f/MWCNTs was prepared by chemical co-sequestration method, and the physical and structural properties of the adsorbent were analysed by FESEM-EDX, TEM, and XRD techniques. Then, the effect of pH changes (2 - 10), contact time (15 - 240 minutes), adsorbent amount (0.02 - 0.1g), and initial concentration of arsenic (2 - 12 mg/l) was investigated and optimized. The isotherm and kinetics of the reaction were also determined. Results show that the optimal conditions for arsenic removal with magnetic adsorbent are pH= 2, 0.02 g of adsorbent at a concentration of 6 mg/l, and ambient temperature. Also, the fit curves and Freundlich and pseudo-quadratic models were found as optimal isothermal and kinetic models, respectively. The fits of the Freundlich (R2 = 0.9881) and pseudo-second order (R2 =1) models were acceptable. https://hydro.tabrizu.ac.ir/article_11143.html Groundwater is an important water resource in arid and semiarid regions and its quantitative/qualitative analysis is very important. In Tabriz plain, due to the reduction in annual amounts of precipitation and consequently, reduction of surface runoff, groundwater resources play key rule in supplying agricultural, drinking and industrial consumptive sections. The goal with the present study was evaluating the groundwater resources in Tabriz plain qualitatively from agricultural irrigation viewpoint, as well as analyzing the spatial variations of EC, Cl, TDS and SAR through employing the geostatistical methods. The observational records of86 wells in this region, covering a period of 17 years (2004-2017), were used to assess the applied methodology. Comparing the Kriging, co-kriging (with Gaussian variogram) and IDW methods showed that that the co-Kriging with Gaussian variogram provided the most accurate results inn term of the lowest scatter index (SI) values. The results of the groundwater quality classification (using Wilcox diagram) and EC/ SAR zoning showed that the groundwater quality in the Tabriz plain is semi saline to saline in most of the cases, which might be linked to the higher amounts of withdrawals from the aquifer. Groundwater is an important water resource in arid and semiarid regions and its quantitative/qualitative analysis is very important. In Tabriz plain, due to the reduction in annual amounts of precipitation and consequently, reduction of surface runoff, groundwater resources play key rule in supplying agricultural, drinking and industrial consumptive sections. The goal with the present study was evaluating the groundwater resources in Tabriz plain qualitatively from agricultural irrigation viewpoint, as well as analyzing the spatial variations of EC, Cl, TDS and SAR through employing the geostatistical methods. https://hydro.tabrizu.ac.ir/article_12703.html Undoubtedly, water has been the cornerstone of human civilization and is also one of the most vital needs for sustainable and satisfying life throughout human life . The largest source of fresh water available to humans is located in the basement and inside geological formations. For a long time, all human civilizations have been built along with reliable water resources and now it has an important role in the comprehensive development of urban and rural areas. Increasing the amounts of industrial, domestic and agricultural pollutions is one of the major causes of groundwater degradation. Study of the there resources from the quantitative/qualitative viewpoints is of the crucial importance, especially in arid semi-arid regions, where considerable amounts of them are withdrawn. So far, numerous studies have been carried out to analyze the groundwater recourses quality and quantity through using different methods When dealing with development plans of a region, groundwater quality is one of the major parameters that should be considered. Groundwater quality should be assessed from physical and chemical viewpoints and meanwhile, groundwater quality index (WQI) is one of the most important in this case. Using data from 86 wells inn Tabriz Plain, WQI was computed (with using So4, Cl, Hco3, Total Dissolved Solids, Total Hardness, Electric Conductivity, Na, Ca, Mg, PH and K) for both dry and wet seasons during a 15 years period. The zoning maps were prepared using Kriging and Co-kriging methods through analysis of the various models. Overall analysis showed that Exponential Model in Kriging and Co-Kriging methods had better results than other models and moreover, the obtained results revealed that the groundwater quality of the studied region was poor for drinking consumption at the same period time. https://hydro.tabrizu.ac.ir/article_12806.html Evapotranspiration is one of the most effective components of the water balance of a catchment area in arid and semi-arid regions of the world, and its correct estimation is very important for the optimal management of the country's water resources. In this study, using SEBAL algorithm and MODIS sensor satellite images, was estimated the actual evapotranspiration rate of Lake Urmia catchment. Lysimetric data were used to evaluate the accuracy of the actual evapotranspiration rate results. A number of MODIS sensor products along with ground data were used to generate the three major semesters of energy balance fluxes. The converted images were imported into ILWIS software. Finally, R2, MBE and RMSE statistical indices were used to evaluate the performance of the algorithm.The results showed that the highest amount of net radiation reached the earth's surface occurred in May and the maximum amount of noticeable radiation flux occurred in April. Among the terms of energy balance fluctuations, the earth heat flux term has the least effect. The highest rate of actual evapotranspiration occurs in July and the total annual height of actual evapotranspiration is 1748 mm, of which about 65% occurs between May and October. The value of R2 index was 0.84, MBE was 0.53 mm and RMSE was 1.3 (indicating the acceptable accuracy of the algorithm). Spatial pattern of evapotranspiration showed that agricultural lands located in the western, southern and eastern parts of the catchment have the highest values of actual evapotranspiration height and time changes showed that the values of actual evapotranspiration height increased from April to July. https://hydro.tabrizu.ac.ir/article_14451.html Jareh River has decreased in quality in some areas to the downstream. The purpose of this study was to evaluate the hydrogeological relationship between Ramghan salt dome and groundwater in the region. XRD analysis was performed on the cores extracted from 10 geotechnical boreholes. The results of XRD analysis indicate the absence of extensive salt layers in outcrop of salt diapir. Groundwater flow in the alluvial aquifer cannot play a major role providing salinity of downstream groundwater and the dissolutions of halite, as the main source of salinity of groundwater, may have occurred in other areas of the dome. Based on the results, the dissolution of evaporites, especially the halite within the Ramghan salt dome, is mainly responsible for increasing the salinity of groundwater and surface water in the study area. With regarding changes of the hydrochemical properties such as water type and salinity, surface water can be classified into four groups A to D. Group A is fresh water with EC values of 600-725 µS/cm, Group D is the accumulated brines on the surface with TDS values more than 300 g/l and the groups B and C are the result of relative mixing of those two groups. The groundwater level is above the river level and the groundwater flows towards the river. Jareh River is a gaining river and the base level of erosion of the study area and groundwater has mixed with surface water in several sections along the salt dome. Accordingly, the groundwater mixed with the river should be attributed to one or a combination of the three following origins: 1) River water that penetrates upstream into the ground, 2) Rainfall that penetrates and percolates to the aquifer through fractures and sinkholes, and 3) Groundwater of karst aquifers that flows to Jareh River through the underground conduits. https://hydro.tabrizu.ac.ir/article_16685.html Areas with geothermal potential naturally have evidence on the surface of the earth, which is used in geothermal energy exploration projects for the initial location of these areas. The purpose of this research is to identify areas a surface geothermal energy potential by combining surface temperature and energy flows obtained the sebal algorithm using the thermal data of the landsat 8 TIRS sensor in the sablan area of ardabil, located in the northwest of the country. For this purpose and to minimize the effect of solar radiation, a one image from Landsat 8 data on June 23, 2021 was used and using SCJM&S single channel(Jiménez & Sobrino) and split window algorithm, the temperature map of land surface observations was determined. Also, the amount of net radiation received by the earth's surface (Rn), the amount of net energy directed to the earth (G) and the amount of solar radiation absorbed by the surface (Rsolar) have been calculated using the energy balance algorithm on the earth's surface (Sebal). By combining these layers of information with surface temperature observations map, the potential areas of geothermal energy were identified and determined. The results showed that there are areas in the cities of ardabil, sareyn and meshgin shahr that have geothermal energy potential and the existence of a natural hot spring in the city of meshgin shahr and sareyn has increased the probability of the existence of geothermal resources and it confirms that the studied area has a high potential for the exploration of geothermal resources. https://hydro.tabrizu.ac.ir/article_18369.html The average deficit of the long-term reservoir volume of the country's aquifers from 1971 to 2022 is equal to 48 billion cubic meters. Therefore, it is inevitable to change the basic approach in the policies and strategies of the water sector. Since 2013, the restoration and balancing plan of underground water resources has been on the agenda of the Ministry of Energy. The aim of this research was to introduce and diagnose the restoration and balancing plan of underground water resources, which was done in three steps. In the first step, the factors affecting the complete failure of the plan's goals, in the second step, the issues and problems in the implementation of each of the case plan projects, and in the third step, the problem analysis and pathology of the plan and restoration and balancing were done. The results showed insufficient legal capacities, lack of effective use of development program rulings and upstream documents in proper organization and attracting the participation of the beneficiary community; Inefficiency and conflict of interest in groundwater management; The existence of conflicts in policies, contradictions in upstream documents and inter-sectoral interests, lack of comprehensiveness in planning, implementation and monitoring of the revitalization and balancing plan are among the effective factors in the complete failure of the plan's goals. https://hydro.tabrizu.ac.ir/article_20275.html Subsidence, a gradual geological phenomenon, is often associated with the decline in underground water levels and excessive extraction of groundwater in aquifer areas. This study focuses on the subsidence dynamics in the Salmas Plain of northwest Iran, examining both geological factors and anthropogenic influences. These factors include the presence of faults, clay layers, organic soils, and areas characterized by a high thickness of the aquifer layer. Human activities, such as mining, organic soil drainage, and groundwater depletion due to harvesting, further contribute to the complexity of subsidence patterns, which appear randomly. Situated in the northwest of Iran, the Salmas Plain encompasses the salt marshes of Lake Urmia in its eastern part. Our research employs the GARDLIF framework and machine learning to delineate the zones of land subsidence in Salmas Plain. Seven critical parameters, namely groundwater level drop, aquifer discharge, aquifer feeding, land use, aquifer environment, and distance from faults, were systematically analyzed. Results indicate a notable subsidence rate of 12 cm per year in the region. Specifically, areas around the city of Salmas and the western and northeastern parts of the aquifer show the highest susceptibility to subsidence. Field observations corroborate the model's predictions, revealing subsidence in the form of sinkholes and cracks in the Salmas city area. The sensitivity analysis underscores the significance of specific parameters in influencing land subsidence. The drop in underground water level (G) and pumping from the aquifer (D) emerge as the most influential, with average changes of 0.27 and 0.15, respectively. In contrast, the distance from faults proves to be the least effective parameter, with average changes of 0.0025. This research not only contributes to the understanding of subsidence in aquifer regions but also underscores the importance of considering both geological and anthropogenic factors in assessing and managing land subsidence risks. https://hydro.tabrizu.ac.ir/article_21646.html In recent years, the water crisis, the decline in groundwater levels, and the reduced sustainability of agriculture have underscored the importance of accurately estimating water infiltration into soil. In this study, water infiltration was simulated using data from 17 infiltration tests and five models: Green-Ampt, Kostiakov, Horton, SCS (Soil Conservation Service), and an artificial neural network (ANN). Statistical evaluation indicated that the SCS model had the best performance due to higher accuracy and lower error compared to the other models, followed by the neural network model in second place. To assess model uncertainty, the fuzzy α-cut method was applied. Results showed that the neural network model had the lowest uncertainty (11% to 21%) in estimating cumulative infiltration, while the SCS model had the highest uncertainty (88% to 61%). The uncertainty analysis revealed that although the SCS model demonstrated higher accuracy, it was more unstable and sensitive to input parameters. This finding suggests a general principle: in the comparison of engineering models, it is essential to consider not only statistical accuracy but also uncertainty and model reliability. For instance, in this study, the SCS method might have been the preferred choice without uncertainty analysis; however, considering both the accuracy and reliability of the neural network model, it can be regarded as the better option. These results also confirm the superiority of data-driven models in the optimal management of water resources.