Search published articles


Showing 9 results for Subject: Hydrogeology
The effects of aquifer and well parameters on Capture Zone and Discharge Zone in alluvial unconfined aquifers
Amin Ahmadi, Manouchehr Chitsazan , Seyed Yahya Mirzaee , Arash Nadri ,
Volume 16, Issue 2 (9-2022)
Abstract
In order to protect water wells, it is necessary to analyze the zones of influence, capture, recharge and discharge zones. Despite much research, this issue still needs further discussion. The purpose of this research is to analyze the capture and discharge zones of water wells in alluvial unconfined aquifers. For this purpose, a hypothetical aquifer was simulated using the Modflow and Modpath models. The accuracy of the numerical model outputs was confirmed by comparison with the analytical calculations, and then the effect of the independent parameters of the well and the aquifer was investigated. This research showed that, contrary to popular belief, changes in hydraulic conductivity, specific yield, bedrock dip, initial thickness, porosity, and heterogeneity do not cause changes in the surface extent of the well's capture zone in the unconfined aquifer.This research has shown that changes in surface recharge, discharge and well location cause many changes in the surface extent of the well capture zone in unconfined alluvial aquifers. Investigation of the effect of pumping time in a single well system showed that the size of the capture zone initially increases, but after a short period, of time, despite the continued expansion of the drawdown cone, its position stabilises. It was found that the change in all the above parameters causes a change in the size of the well's discharge zone. The stability of the above-mentioned areas is very important for the determination of zones for the protection of the quantity and quality of water wells! It has been found that the relative stability of the water level in the aquifer at an appropriate level is necessary, and this requires the management of the aquifer and the allocation of a limited percentage of the aquifer recharge to discharge through wells.
 

Evaluating groundwater hydrochemistry in the Zarabad aquifer (Sistan and Baluchistan province) to determine the quality of the water for agricultural use
Miss Masoumeh Nikbakht, Prof Mohammad Nakhaei, Prof Ata Shakeri, Dr Vahab Amiri,
Volume 16, Issue 4 (1-2023)
Abstract
In this study, the hydrogeochemical and qualitative status of groundwater resources of the Zarabad coastal aquifer in southeast Iran has been investigated. The decreasing order of cations and anions is Na+>Ca2+>Mg2+>K+ and Cl->SO42->HCO3-, respectively. The two most water type are Na-Cl (78%) and Ca-Mg-Cl (22%). The water type, chlorine-alkalinity index, ion ratios, and position of the samples on the Gibbs diagram show that cation exchange (direct and reverse), weathering of silicates and evaporites, and seawater intrusion are the main controlling processes of water chemistry. The ionic ratios of SO42-/Cl-, B/Cl-, and Na+/Cl- indicate that saltwater infiltration increases as the distance from the Rabach River increases, particularly in the northwest and southeast regions. This can lead to a decrease in the quality of water resources. Moreover, the water quality for agricultural use is assessed based on some indices, including electrical conductivity (EC), sodium percentage (Na%), sodium absorption ratio (SAR), residual sodium carbonate (RSC), magnesium absorption ratio (MAR), permeability index (PI), Kelly’s ratio (KR), and USSL and Wilcox diagrams. The results showed that about 60% of the samples had unsuitable quality for irrigation. These samples were located in the northwestern and southeastern parts of the plain. About 40% of the samples have suitable quality for irrigation and are located in the vicinity of the Rabach River.
 

Modeling the relationship between groundwater fluctuation and Dez river discharge in Dezful-Andimshek plain
Khadijeh Kord, Heeva Elmizadeh, Hakimeh Amanipour,
Volume 17, Issue 1 (3-2023)
Abstract
The study area is a part of the Dez River Basin, which is located in the central part of the basin. In this area, due to the climatic conditions, the irregular availability in terms of time and space, the increasing use of water resources and surface water resources, there is a great dependence on the underground water of the region. The main objective of this research is to investigate the factors influencing  the fluctuations of the water level in the Dezful-Andimeshk plain during a statistical period of 20 years. For this purpose, using piezometric well level data and well logs of the study area in WinLog software, maps of the groundwater level and the bottom level of reservoir were prepared using theIDW method. The results of the research showed that the greatest drawdown occurred in north-eastern, south-eastern and western parts of the study area. Asthe amount of precipitation, evaporation and temperature are high in this part, one of the reasons for the decline in these parts can be attributed to the climatic factors of the region. Other factors in the decline of the reservoir level are the main river channel and the high slope of the area. Comparing the changes in the reservoir level with the flow of the Dez River showed that there is a high correlation between the changes in these two parameters with a time interval of one year. Therefore, according to agricultural activities, these limited resources should be harvested, scientifically and fundamentally, the region will be at risk of a serious water crisis in the future.
 

Investigating the groundwater quality of Evan Plain aquifer in Khuzestan province with emphasis on nitrate concentration
Dr Seyed Yahya Mirzaee, Phd Student Zahra Chaghazardi, Dr Manouchehr Chitsazan, Dr Farshad Alijani,
Volume 17, Issue 1 (3-2023)
Abstract
The Evan plain is located in the Khuzestan province in the southwest of Andimshek city. Groundwater is one of the available water resources for irrigation, drinking, and industry in this region. Due to the importance of examining the ground water quality of the Evan plain, hydrochemical parameters and nitrate pollution have been evaluated. Nitrate is one of the most widespread pollutants of ground water in the world. However, few studies have been conducted on this pollutant in the Evan plain. Therefore, to assess the quality of ground water in this area with emphasis on nitrate pollution, sampling was carried out in September of the water year (1400-1401) from 22 wells in this plain. During the sampling, field parameters (temperature, pH, EC), concentrations of major elements (Ca2+, Mg2+, Na+, K+, Cl-, SO42-, HCO32-, CO32-), and nitrate were measured. The results of the factor analysis demonstrated three influencing factors, namely EC, Na+, K+, Mg2+, Ca2+, Cl-, SO42-  (as the first factor), pH and Hco32- (as the second factor), and NO3- (as the third factor), with a total of 89.72% having the most changes in the Evan plain aquifer. The dominant water type in the Evan plain is sulfate-calcite. Hierarchical clustering analysis shows the three clusters for the regionalization of nitrate data. In general, the changes in nitrate ion concentration in the groundwater of the Evan plain are affected by the size of the soil particles, the depth of the groundwater, and the utilization of chemical fertilizers in the area.
 

Prediction of Chloride in Groundwater Using Supervised Artificial Intelligence Committee Machine (SAICM) (Case Study: Sari Plain)
Tahereh Azari, Sakineh Dadashi, Fatemeh Kardel,
Volume 17, Issue 2 (9-2023)
Abstract
Qualitative assessment of coastal waters affected by seawater salinity can be done using the parameter of chloride in groundwater. This research proposes a supervised artificial intelligence committee machine (SAICM) method for accurate prediction of chloride concentration in groundwater of Sari plain. SAICM predicts chloride concentration as the output of the model by non-linear combination of artificial intelligence models. In this research, Principal Component Analysis (PCA) method was used to identify effective hydrochemical parameters related to chloride concentration as input components to artificial intelligence models. Based on the results of PCA, parameters (Na, K, EC, TDS, SAR) were selected as input components of artificial intelligence models. Firstly, four artificial intelligence models, Sogno fuzzy logic, Mamdani fuzzy logic, Larsen fuzzy logic and artificial neural network were designed to predict chloride concentration. Based on the modelling results, all the models showed a good fit with the chloride data in Sari Plain. Then, the combined SAICM model was built, which combines the prediction results of 4 separate AI models using the nonlinear ANN combiner and determines the chloride concentration more accurately. The results show that the proposed SAICM can estimate chloride concentration with much higher accuracy than individual methods.

Dynamic systems modeling of consecutive multi-purpose reservoir dam by using Vensim software
Somayeh Zarei Doudeji, Rahim Bagheri, Hadi Jafari,
Volume 17, Issue 2 (9-2023)
Abstract
The science of system dynamics is a management tool capable of simulating complex systems in water resources. In this research, the model of the dynamic system of multi-purpose consecutive Kardeneh-Sana dams located in Bushehr province has been simulated. The purpose of this modeling is to realize the different needs of the dam (drinking, environment and industrial agriculture) before its construction and also to investigate the effect of construction of the upstream dam on the supply of the downstream dam. The results were studied after calculating the annual and monthly percentage of volume and time supply of the different needs and source of supply, as well as considering two drinking water wells to provide drinking water in the months when the dam is not able to provide drinking water and the maximum The discharge of the current drinking water pipeline of the region was carried out. Six management scenarios were considered for modeling, and finally the sixth scenario was considered as the most optimal scenario. In order to evaluate the model, the simulated values were compared with the observed values of the water volume of Sana Dam. The results indicate that the volume supply of drinking, environment and industrial agriculture needs of Kardeneh Dam is 97.66, 96.59 and 82.76 respectively, and also the volume supply of environment and agriculture needs from Sana Dam is 100, 48 respectively. It is 83.0%, which is within the acceptable range of the Ministry of Energy. Based on this research, it was determined that by modeling based on model evaluation indicators including percentage of volume supply and percentage of time supply of different needs, it is easy to determine the effect of management and exploitation policies on the way of determining and allocating resources. Water observed and made the most optimal decision.

The position of groundwater studies in tunnel projects in Iran
Massoud Morsali,
Volume 17, Issue 3 (12-2023)
Abstract
Tunneling in a saturated environment and the intrusion of groundwater flow into tunnels during excavation is one of the most serious problems in tunneling projects. Water ingress into the tunnel can lead to damage to tunnel construction equipment, personnel, the excavation process, etc. The hydrogeological studies of the springs along the tunnel route and the estimation of the water entering the tunnel also investigate the possibility of drying up or reducing the water level of the tunnel route. The hydrogeological studies of the springs along the tunnel route and the estimation of the water inflow into the tunnel will also examine the possibility of drying up the springs or reducing the water level of the tunnel route. On the other hand, the complications of water ingress into the tunnel and the lack of an accurate and appropriate method increase the importance of these studies. Experimental and analytical methods are available to predict water inflow into a tunnel. In this article, in addition to presenting the general process of carrying out hydrogeological studies of tunnels, the weight percentage of hydrogeological studies and the problems associated with them are discussed. On average, more than 30% of all tunnel problems are related to groundwater, but less than 5% of studies are carried out in this field. The disproportionate weight of the above two cases and its causes are among the other cases discussed in this article.

Effect of Tunnel Excavation of Tehran Metro Line 6 on Groundwater and Ali Spring in Shahr-e-Rey
Professor Hamidreza Nassery, Koosha Tamimi, Dr Farshad Alijani, Dr Sadegh Tarigh Azali,
Volume 17, Issue 3 (12-2023)
Abstract
The development of underground transportation activities in cities, such as tunnel boring, may exert short-term or long-term effects on the groundwater and springs of such areas. The construction of the tunnel of Tehran Metro Line 6 (TML6) through alluvium and carbonate rocks of Ali Spring has aroused concern due to the caused fluctuations in discharge and temporary dryness of the spring. The hydrochemical properties of the groundwater and catchment area were investigated to find a connection between the aquifers around the spring and determine the major aquifer feeding it. The estimated volume of water penetrated to the tunnel and the most greatly affected area by the water leakage into the tunnel was determined using analytical methods of water leakage into the tunnel and the DHI method. The statistics for precipitation with the changes in the discharge of the spring before and after the excavation of the metro tunnel were compared to evaluate the changes in the discharge of the spring with the precipitation in the area. The results showed that the metro tunnel excavation has dramatically affected the hydrological system of the area and discharge of the Ali Spring. Moreover, continuing the extraction may produce adverse effects on the discharge of other springs and wells and alter the flow system of the area temporarily or forever.

The drawdown cone of influence zone in water wells in unconfined alluvial aquifers and the influence of physical parameters of the aquifer on it
Amin Ahmadi, Gholamreza Mirzavand, Maryam Zebarjad,
Volume 17, Issue 3 (12-2023)
Abstract
The zone of influence of the well is the area where the activity of the well changes the water level. The zone of influence is important in determining the protection zones; however, in this regard, reliable relationships have not yet been presented and their lack of relationship has not been confirmed; and this is due to the lack of accurate knowledge of the zone of influence in some aquifers. This study was carried out using the MODFLOW model to know the effect of aquifer physical parameters on the drawdown cone in an unconfined alluvial aquifer with a sloping water surface; and since no such research has been reported so far, the results are innovative. The results showed that although it is possible to ignore the effect of a well in parts of the aquifer due to measurement and presentation limitations, in practice the influence zone of each well will extend to the outer physical boundaries. It was found that two types of real and theoretical drawdown cones can be discussed in the influence zone and each should be analyzed separately. It was found that parameters such as hydraulic conductivity, saturation thickness, transmissivity, horizontal anisotropy, bed slope, and amount of recharge in sloping unconfined aquifers have a dual effect on the drawdown cone, and if their high values decrease the drawdown in short distances, they increase the drawdown in long distances. It was found that normal heterogeneity does not change much on the drawdown cone, and the reason is the opposite effects of hydraulic conductivity and specific yield on the drawdown value. It was found that hydraulic conductivity, horizontal anisotropy and specific yield have a strong effect, but vertical anisotropy and heterogeneity have a negligible effect on the drawdown cone.

Page 1 from 1     

© 2024 CC BY-NC 4.0 | Journal of Engineering Geology

Designed & Developed by : Yektaweb