https://gnf.khu.ac.ir/ Kharazmi Journal of Earth Sciences en daily 1 Mon, 22 Dec 2025 00:00:00 +0330 Mon, 22 Dec 2025 00:00:00 +0330 https://gnf.khu.ac.ir/article_4111.html The Shourab prospect, located in the west of Central Iran, exhibits significant hydrothermal alteration and trace element anomalies linked to potential Iron Oxide Copper-Gold systems (IOCG) mineralization. Alteration zones are characterized by chlorite, calcite, quartz, biotite, K-feldspar, albite, actinolite, sericite, and tourmaline, with variable intensities across mafic to felsic volcanic units. Molar element ratio (MER) and alteration indices (AI and CCPI) were employed to quantify alteration processes, revealing progressive alteration from peripheral propylitic zones to core potassic and sodic-calcic assemblages. Spatial geochemical anomalies of elements such as Au, Cu, U, Mo, Ba, Sm, Ce, and La strongly correlate with specific alteration zones. Mineralogical evidence and statistical analysis of lithogeochemical indices such as iron, potassium, and rare earth element enrichment along with hydrothermal alteration indices, indicate a genetic similarity between this magmatic-hydrothermal system and IOCG type systems. Host rock composition, fluid-rock interaction, and structural controls significantly influenced alteration styles. This work provides a comprehensive framework for identifying hydrothermal footprints of IOCG mineralization in complex volcanic-intrusive terrains and contributes to future exploration strategies in the west Central Iran. https://gnf.khu.ac.ir/article_4092.html The Alvand intrusive pluton, located in Hamadan Province within the Sanandaj–Sirjan zone, exhibits a well‑developed shear zone along its northern margin, southeast of Heidareh Qazi‑khan village, at the contact between the intrusion and the host rocks. The studied shear zone is parallel to the intrusive contact, trending north–south and dipping steeply to nearly vertical. In this area, the transition between the metamorphic host rocks and the intrusive body is gradual, and granite layers have been injected into the schists as dikes of variable thickness. These vertical dikes are completely deformed and mylonitic, and even the host rocks display deformation features. Kinematic indicators reveal a dominant reverse movement with a minor dextral (right‑lateral) strike‑slip component within the shear zone. To evaluate the nature of deformation, samples of mylonitic granites were collected perpendicular to the shear zone and to the intrusion–host contact. The magnitude of shear strain and consequently the proportion of simple‑shear and pure‑shear components were determined using two techniques based on porphyroclast geometry: the Porphyroclast Aspect Ratio method and the Rigid Grain Net method. Kinematic and shear‑strain analysis indicates that the Wk values range from 0.56 to 0.77, suggesting that the studied shear zone represents a general shear zone, involving a combination of simple and pure shear components. https://gnf.khu.ac.ir/article_11574.html Archie’s coefficients are among the most fundamental inputs for estimating water saturation in hydrocarbon reservoirs. However, in many reservoir evaluations, these parameters are assumed to be constant and independent of the physical characteristics of the pore network. This assumption can introduce significant uncertainty in water saturation estimation in heterogeneous carbonate reservoirs where pore and throat geometries vary considerably. In this study, the role of pore‑throat diameter in controlling variations of Archie’s coefficients in the Permian–Triassic carbonate reservoirs of the Persian Gulf is quantitatively assessed using a multiple regression approach. Core-derived porosity and permeability data, mercury injection capillary pressure (MICP) analyses, and formation resistivity factor measurements from a gas well in the western Persian Gulf were utilized. Pore‑throat diameters at various mercury saturation levels were calculated and their relationships with porosity, permeability, cementation exponent, and formation resistivity factor were evaluated. Results indicate that the pore‑throat diameter at 10 percent mercury saturation shows the strongest correlation with porosity and permeability, providing a suitable basis for rock typing. Archie’s coefficients calculated within the identified rock types demonstrate that these parameters are not constant and systematically vary with changes in pore‑network geometry. Furthermore, multiple linear regression analyses reveal that rock typing significantly improves coefficients of determination in the correlations between petrophysical and electrical properties, with the strongest improvements observed for the formation resistivity factor and cementation exponent. These findings highlight that incorporating pore‑throat diameter and rock typing offers a more robust framework for estimating Archie’s coefficients and reducing uncertainty in water saturation calculations within heterogeneous carbonate reservoirs. https://gnf.khu.ac.ir/article_4112.html Reservoir compartmentalization is a phenomenon whereby the presence of flow barriers divides a hydrocarbon reservoir into separate zones with distinct flow behaviors. Accurate identification of these flow barriers and the various reservoir zones is crucial for optimal field management, accurate reserve estimation, proper well placement design, and, in general, for all future field development decisions. Given the significance of studying reservoir compartmentalization in Iranian oil fields, this paper investigates lateral continuity in the Bangestan reservoir in one of the fields from the Dezful Embayment. For this purpose, a novel and efficient approach was employed, utilizing the structural characteristics of asphaltenes through Fourier-transform infrared (FTIR) spectroscopy. Asphaltenes are macromolecular compounds with a structure similar to kerogen. Due to their stability against secondary processes, such as biodegradation and water washing, they serve as reliable indicators for obtaining oil fingerprints and assessing fluid composition heterogeneity within a reservoir. In this study, four crude oil samples were collected from producing wells in the Bangestan reservoir and analyzed by FTIR to determine various structural indices, including aliphatic, aromatic, branched, and substitution indices, to compare the structural characteristics of different asphaltenes. The results showed that sample S-1 exhibited significant differences in structural indices and chemical composition compared to the other samples (S-2, S-3, and S-4). This issue indicates a difference in crude oil fingerprints among the studied wells, which is attributed to the presence of a flow barrier in the Bangestan reservoir. To confirm these results, pressure data were also analyzed, which revealed a different pressure gradient for well S-1 compared to the other wells, further supporting the presence of a flow barrier. Therefore, the use of structural characteristics of asphaltenes is considered an efficient, low-cost, and straightforward method, providing results comparable to reservoir engineering data in identifying reservoir discontinuities. https://gnf.khu.ac.ir/article_4093.html Groundwater is one of the key sources of water supply for various uses in Khuzestan Province. In recent years, especially in the agricultural areas of the Gotvand Plain, it has undergone significant quantitative and qualitative changes. The aim of this study is to predict the effectiveness of the restoration and balancing plan projects (has started since 2008) on the groundwater‑level balance of the Gotvand aquifer using the MODFLOW numerical model. In this research, changes in the water‑table level and the aquifer water budget were examined under different management scenarios through the years 2021 to 2022, including deactivating and sealing illegal wells, resolving the status of “Form one” wells, and revising and adjusting abstraction permits for agricultural well. The simulation results showed that eliminating illegal wells has the greatest impact on improving the aquifer condition. In this scenario, the water‑table level increases by approximately 3 meters in the southern parts of the aquifer and about 0.3 meters in the northern parts, while the aquifer storage increases by around 8 million cubic meters. In contrast, resolving the status of “Form one” wells results in only about a 0.9‑million‑cubic‑meter increase in storage and does not produce a noticeable change in the water‑table level. Overall, the findings indicate that sealing illegal wells can be considered the most effective management action for improving the quantitative status of the Gotvand aquifer. https://gnf.khu.ac.ir/article_4113.html Monitoring vegetation cover changes and environmental anomalies is essential for ecosystem management, precision agriculture, and early warning systems. Given the complexity of spatiotemporal environmental patterns, multi-temporal satellite data offer an efficient approach to track gradual and abrupt changes. In this study, time-series data from the Sentinel-2 sensor and spectral indices NDVI, EVI, and NBR are used as indicators sensitive to chlorophyll content and severe disturbances, along with lightweight, unsupervised algorithms Isolation Forest, Local Outlier Factor (LOF), and One-Class Support Vector Machine to identify anomalies. Model performance evaluation shows that the Isolation Forest algorithm provides the most balanced and robust performance (Accuracy = 0.886, Precision = 0.065, Recall = 0.250, F1 = 0.103). The Local Outlier Factor algorithm demonstrated higher sensitivity to localized patterns but had lower stability in noisy data (F1 = 0.069). The One-Class SVM adopted a more conservative labeling approach and was mostly effective at detecting severe disturbances, especially with the NBR index (F1 = 0.035). Overlap and Distinction Analysis of Indices that NDVI captures gradual chlorophyll decline, EVI performs better in dense vegetation, and NBR plays a crucial role in identifying severe events such as wildfires and droughts. The concurrent use of these indices broadens the detectable range from subtle fluctuations to large-scale disturbances. Findings show that integrating freely available Sentinel-2 data with lightweight machine learning models yields a scalable, reproducible, and efficient framework for large-scale environmental anomaly monitoring. This approach minimizes reliance on costly field data and enables practical applications in drought monitoring, environmental-crisis management, ecosystem health assessment, and smart agricultural planning. For future work, integrating moisture- and temperature-related spectral data, higher temporal resolution time series, and metaheuristic parameter tuning is recommended to further enhance robustness and accuracy. https://gnf.khu.ac.ir/article_4094.html Vegetation cover is one of the key elements in maintaining ecological balance and the sustainability of natural resources, playing an effective role in regulating the water cycle, reducing soil erosion, and preserving biodiversity. This cover interacts directly with surface soil moisture, and its changes can indicate ecological transformations in sensitive environments such as Lake Urmia. Examining the correlation between vegetation cover and surface moisture is essential for a better understanding of environmental trends and the sustainable management of water resources. In this study, using deep learning methods and the analysis of remote sensing indices NDVI and NDWI, changes in vegetation cover and surface moisture in four regions around Lake Urmia from 2015 to 2024 were investigated, and the 2025 values were predicted. Modeling was conducted using deep neural networks, and its accuracy was evaluated using the Root Mean Square Error (RMSE) criterion. Statistical analysis of the results showed that the southern and western regions experienced the most fluctuations. Furthermore, the correlation coefficient between NDVI and NDWI across all regions was negative and significant (r between -0.83 and -0.96, p < 0.01), indicating the negative impact of increasing vegetation cover on surface moisture. These findings, while confirming a strong inverse relationship, highlight the importance of integrating vegetation cover and moisture data in long-term monitoring, predicting ecological changes, and adopting effective management strategies for the restoration of Lake Urmia. https://gnf.khu.ac.ir/article_4114.html The anisotropic elastic stiffnesses of granular soil sediments play an important role in analyzing many geotechnical and geological engineering problems. In this study, the feasibility of calculating drained elastic stiffnesses in saturated granular soils based on undrained features was investigated. By assuming cross-anisotropy in granular soils, a set of equations from the theory of elasticity was extracted from the literature and then combined with an experimentally developed relationship in this study to establish a link between drained and undrained parameters. Subsequently, a novel approach was proposed for computing the drained anisotropic Young’s moduli from two anisotropic components of the shear modulus and the vertical component of the Young’s modulus under undrained conditions. To evaluate the accuracy and reliability of the proposed approach, data related to anisotropic elastic parameters from 46 laboratory tests conducted on seven different soil specimens representing three types of sand from various sites worldwide were compiled from the literature. The drained anisotropic Young’s moduli for each test were then calculated using the proposed method and compared with directly measured values. The results showed a strong agreement between the calculated and measured moduli, confirming the validity and efficiency of the developed approach. The findings of this study can serve as a reliable basis for the rational and cost-effective characterization of anisotropic elastic stiffnesses in saturated granular soils using nondestructive seismic testing techniques. https://gnf.khu.ac.ir/article_4095.html Split-window algorithm is an effective method for determination of land surface temperature. The main goal of this research is application of Split-window algorithm for determination of surface temperature pattern of Mesijune salt dome in the southeastern of Fars province in the Zagros Mountains. Land surface temperature (LST) analysis has made using of Landsat 8 TIRS and OLI sensors. The results of surface temperature pattern show the highest temperature (36°C) at the summit and the lowest temperature (30°C) at the marginal part of the salt dome. It seems that the higher temperature at the dome summit is related to the connection between the central parts of the dome with the basement salt column. While the lower temperature of the marginal parts of the dome can be due to the lack of connection between the salt dome and the salt source of Hormuz Series. https://gnf.khu.ac.ir/article_4115.html The Rudbal Dam, with a reservoir capacity of 82 million cubic meters, is located in the Rudbal Valley near Darab City. The dam and reservoir are in contact with Sarvak limestone and radiolarite on the right and left abutments, respectively. The possible water leakage route includes an inlet window, transfer route, and outlet window. The inlet window comprises Sarvak limestone and river alluvium, in part of which the grout curtain has been constructed. Since the reservoir was filled in 2016, persistent water leakage has occurred. The purpose of this study is to investigate the physicochemical characteristics of the water sources around the dam to determine the path of water leakage through or around the grout curtain. For this purpose, the physicochemical characteristics of 83 water sources were measured. Water sampling was also carried out at 30 points, and the concentrations of its main elements were determined. By evaluating the results of the analyses, the relationship of the samples with the reservoir water was determined. Examination of characteristics such as water type, electrical conductivity, and temperature showed that the inlet window at the dam site had not been completely sealed by the grout curtain, allowing some water to leak. By considering that the exact path of water leakage cannot be determined based on the results of a single sampling step, it is recommended to conduct a complementary isotopic and hydrochemical study. https://gnf.khu.ac.ir/article_4096.html The Kowsar Dam is one of the great reservoir and is important due to supply of water for a large part in the south and southwest of the country. The aim of this study was water quality evaluation of the Kowsar Dam watershed. To achieve this goal, eighteen stations were selected for sampling along four tributaries of the Kowsar Dam and totally 72 samples were collected for analysis of chemical and biochemical parameters from January 2023 to October 2023. The maximum value of the physicochemical parameters i.e. electrical conductivity (EC), pH, Ca, Mg, Na, K, HCO3, SO4, Cl, NO3, O2, BOD and ORP were 6536(micromohos/cm), 8/71, 23, 7, 33, 6,17,44(meq/l), 27,12, 27(mg/l) and 35(mv), respectively. The lowest values were 412(micromohos/cm), 7/4, 2/4, 1/2, 0/19, 0/01, 2/75, 0/76, 0/15 (meq/l), 4/2, 0/17, 0/14(mg/l) and -229(mv) respectively. The average value of EC, NO3, DO, and BOD were 1448 (micromohos/cm), 5/9, 8/2 and 5/5 (mg/l), respectively for the reservoir water in the four periods of sampling. The variation domains of the qualitative parameters were quite significant indicating the natural and anthropogenic components effect, on input waters into the Kowsar Dam and variations of NO3, BOD and DO concentration represent anthropogenic impacts. In order to understand the conditions governing quality of water resources, multi variation statistics methods, such as HCA (Hierarchy Clustering Analysis), FA (Factor Analysis) were accounted. https://gnf.khu.ac.ir/article_4116.html In recent years, Hamzeh city, located to the east of Dezful, has faced increasing nitrate contamination in drinking water wells, with landfill leachate and urban wastewater proposed as the main potential sources of pollution. To investigate the origin of nitrate and the influence of geological factors, groundwater samples were collected from ten pumping wells during January 2018, August 2018, and November 2018. The samples were analyzed for major ions and nitrate concentrations. Statistical analysis, factor analysis, saturation indices, Piper diagrams, and electrical conductivity (EC) and chloride contour maps identified halite dissolution as the most significant geological process controlling groundwater hydrochemistry. Based on hierarchical cluster analysis and self-organizing maps (SOM), the samples were classified into three distinct groups. Group 1, located in the northern part of the study area, is characterized by the lowest EC values (approximately 500 µmho/cm) and dissolved solids. Group 3, situated in the southern part of the area, exhibits the highest EC values (approximately 1000 µmho/cm) and dissolved solids, while Group 2, located in the central part of the study area, shows intermediate characteristics. The progressive increase in EC from Group 1 to Group 3 is attributed to halite dissolution within the Aghajari and Lahbari formations. Previous analyses showed no significant correlation between nitrate and other hydrochemical variables. Nitrate contour maps indicate that the highest nitrate concentrations occur in the southern part of the city, coinciding with the direction of groundwater flow. Additionally, elevated nitrate concentrations were observed in agricultural areas at the end of the growing season. Therefore, urban wastewater is identified as the primary source, and agricultural activities as a secondary source of nitrate contamination in the study area, while no significant impact of the landfill on groundwater quality was detected. Overall, the results demonstrate the effectiveness of the SOM approach in clustering groundwater samples and identifying the dominant factors affecting groundwater quality. https://gnf.khu.ac.ir/article_4097.html Mehdi Abad copper deposit is located in 160 km northeast of Birjand, in South Khorasan province and in the Tertiary volcanic zone of the Lut Block. The major rock units of the study area have Eocene age and include andesitic lavas (andesite, trachyandesite, and pyroxene andesite), pyroclastic units (agglomerate and tuff) with jasper veins. Copper mineralization in this region is epigenetic along lava and pyroclastic units with andesitic composition along with tuff. The main ore textures include vein- veinlets, open space filling, disseminated and replacement. The ores contain primary minerals chalcocite, bornite, chalcopyrite and pyrite and the secondary minerals covellite, secondary chalcocite, cuprite, malachite, azurite, chrysocolla, hematite, goethite and limonite. The most important alterations accompanied with mineralization include carbonatic-silicic, argillic, chloritic, and Fe-oxide alterations that the amount of carbonatic-silicic alteration increases with closing to mineralization zones. Disequilibrium textures such as chemical zoning, sieve texture, rounded and gulf shape margins observed in phenocrysts of these rocks. Geochemical studies results show that these lavas belong to high to medium-K calc-alkaline series. Enrichment in LILE and LREE, depletion in HFSE and HREE in these rocks suggests active continental margin volcanic arc magmatism. Based on tectonic discrimination diagrams, Mehdi Abad area lavas are related to subduction zone and active continental margin that has been contaminated with crustal material while ascending to the surface. In this area, copper-rich magma has impacted the earth's surface while ascending from the subduction zone, creating a set of volcanic rocks with an intermediate composition in the form of lava and pyroclastics on the earth's surface, which are host rocks for copper mineralization. https://gnf.khu.ac.ir/article_4098.html This study aims to monitor and distinguish the origin of ground surface elevation changes in the Gol-e-Gohar mining area using a time-series analysis of 16 Sentinel-1 SAR images acquired between 2017 and 2025, applying the SBAS-InSAR technique. The results reveal that the highest magnitude of surface lowering occurs within mining pit areas, with rates exceeding 300 mm/year, primarily driven by excavation activities, artificial topographic modifications, and mechanical processes, and therefore not representative of true aquifer-related subsidence. In contrast, regional and continuous land subsidence is observed in the Chah-Deraz Plain, with an average rate of approximately 10 mm/year, and in the agricultural lands east of the Sirjan salt flat, with an average rate of about 7 mm/year. These lower but spatially coherent subsidence patterns are consistent with long-term groundwater level decline. The Sirjan salt flat exhibits complex surface deformation behavior influenced by processes such as evaporite dissolution and moisture variations, which may produce signals similar to subsidence. The findings demonstrate that failure to differentiate mining-induced deformation from hydrogeological subsidence may lead to significant overestimation of subsidence hazards. This study highlights the necessity of a source-based, differentiated interpretation framework for accurate hazard assessment, sustainable groundwater management, and informed decision-making in mining regions. https://gnf.khu.ac.ir/article_4117.html Heterogeneity of carbonate reservoirs resulting from lithological, textural, and diagenetic variations makes fluid flow behavior complex and unpredictable. This study was carried out to perform a comparative analysis of petrophysical and statistical methods in reflecting the geological attributes of the Kangan Formation in the central Persian Gulf. Core data and thin sections were analyzed to examine the relationships between geological characteristics and petrophysical and statistical approaches. Porosity and permeability, the percentage of lithologic components, and diagenetic parameters including the type and rate of cementation, compaction, and dolomitization have been used. Four approaches were employed for data classification, including (1) the Winland method, (2) the Flow Zone Indicator (FZI), (3) the Jenks statistical method based on porosity and combined porosity–permeability, and (4) a newly defined Geological Quality Index derived from the integration of dolomite content, effective porosity, and the rate of cementation as the main controlling factors of reservoir quality. The results showed that for all methods, reservoir quality increases from the lower to the upper groups and is accompanied by increasing dolomite, decreasing cementation and decreasing anhydrite. In the FZI method and in the Jenks method based on GQI, the separation of rocks in terms of lithologic and petrophysical characteristics was more orderly and more interpretable than with the other methods. Mean porosity and permeability vary from about 8% and 3 mD in the lower groups to more than 22% and 230 mD in the higher groups, which indicates a strong correlation between reservoir quality and diagenetic processes. The Winland method defined the overall boundaries well but was less sensitive to lithological differences. Overall, the results of this study indicate that combining geological data with statistical and petrophysical methods, can provide a more accurate and realistic representation of reservoir heterogeneities in carbonate formations and can be applied in modeling complex reservoirs. https://gnf.khu.ac.ir/article_4118.html The Urban Heat Island (UHI) phenomenon, a significant outcome of urbanization and industrialization, leads to elevated land surface temperatures in urban areas compared to their surroundings. This study investigates the seasonal variations of Land Surface Temperature (LST) and the intensity of the Surface Urban Heat Island (SUHI) in Isfahan County using data from MODIS and TIRS sensors. Satellite images from 2018 to 2023 were retrieved and processed within the Google Earth Engine (GEE) environment. Three different methods—based on temperature differences between urban areas and rural, agricultural, and water body zones—were applied to calculate SUHI intensity. The results show that SUHI intensity is higher during the nighttime, whereas an Urban Cool Island effect is observed during the daytime, underscoring the significant role of bare soils and wetlands in creating a thermal inversion of the heat island. Vegetation cover, albedo, and elevation were identified as the most important biophysical variables affecting land surface temperature, with significant correlations found between these variables and LST. The highest vegetation cover occurs in spring, contributing to temperature reduction through evapotranspiration. Additionally, increased albedo reduces heat absorption by the land surface. The findings highlight the prominent role of thermal interactions among urban, rural, and aquatic areas in shaping SUHI and emphasize the importance of managing vegetation cover and high-albedo materials to mitigate the phenomenon's negative impacts. In semi-arid cities such as Isfahan, the urban heat island effect may manifest as an urban cool island during the day and a heat island at night; therefore, precise modeling requires remote sensing data from both day and night, along with consideration of accuracy-related indices. https://gnf.khu.ac.ir/article_4119.html Nitrate is one of the most important groundwater contaminants in the world, capable of causing environmental problems and posing risks to human health. This study investigated groundwater quality, nitrate concentration, and its sources in the Izeh Plain aquifer, as well as the impact of land use on this contamination. For this purpose, samples were collected and analyzed from 21 production wells during both the wet and dry seasons of the 2021-2022 hydrological year. The results indicated that the groundwater type is mainly bicarbonate-calcium and bicarbonate-magnesium, and approximately 23.81% of the samples exceeded the permissible nitrate concentration limits set by Iranian drinking water standards and the World Health Organization. Nitrate concentrations in the dry season ranged from 13.40 to 103 mg/L, with an average of 37.31 mg/L, while in the wet season they ranged from 9 to 125.7 mg/L, averaging 34.34 mg/L in the aquifer. Mapping of nitrate distribution confirmed that the areas with the highest contamination are located around the Ab Bandan wetland in the southeast, the southern margin of the Izeh Plain, and the southwest of this city. Integration of ionic ratio data (NO3⁻/Cl⁻, K⁺/Cl⁻, and Cl⁻/Na⁺) and factor analysis demonstrate that the primary sources of nitrate in this aquifer stem from excessive use of nitrate fertilizers, and lack of a sewage network and sanitation treatment plant in the region. This finding is further corroborated by the overlap between the land use map and the nitrate zoning map of the area. https://gnf.khu.ac.ir/article_4120.html The Zagros collision zone results from convergence between the Arabian and Eurasian plates and trends NW–SE. Within this framework, the Saqqez–Baneh structural zone—part of the northwestern Zagros orogen and the Sanandaj–Sirjan metamorphic–igneous belt—exhibits a NE–SW structural trend, markedly different from the overall Zagros trend. Since the tectonic evolution of this zone is closely linked to the Zagros orogen, its study provides valuable insight into the continental deformation history of the region. Kinematic, geometric, and dynamic analyses have enabled reconstruction of the paleostress field and the orientation of the principal compressional and extensional axes responsible for deformation in the thrust belt. Field observations reveal no clear evidence for vertical-axis rotations or local stress-field perturbations around the thrust zone. The northern and southern sectors—despite their nearly perpendicular trends—represent components of a pre-existing structure formed under a homogeneous stress regime during thrust emplacement. Each segment exhibits its characteristic structural geometry and kinematics depending on its relation to the shear zone. Structural data indicate that while the northern segment functioned as a typical Zagros-style thrust, the southern segment operated as a lateral ramp, parallel to the Saqqez–Baneh trend, accommodating left-lateral oblique-slip motion. This inherited structure facilitated westward propagation of the main thrust front and acted as a transverse element during structural evolution. Thus, the Saqqez–Baneh structural zone—similar to the well-known Muteh–Lahbid transverse trend—demonstrates that tectonic processes associated with the opening and closure of the Neo-Tethys did not fully rework the southwestern margin of the Central Iranian microcontinent. https://gnf.khu.ac.ir/article_4121.html To investigate the enviromental geochemistry of potentially toxic elements (PTEs) in urban and agricultural soils of Islamshahr, south of Tehran, 21 top soil samples were collected and the total concentrations of PTEs were measured by an ICP-OES device. The obtained data were analyzed through the calculation of geochemical indices and the application of statistical methods. Based on the average values of the enrichment factor, geoaccumulation index, single factor index, Nemerow integrated pollution index (NIPI) and potential ecological risk index (PERI), the studied soil samples are polluted with Cd, Pb, Zn and Mn. The statistical analyses indicate that Cr, Ni, Fe, Zn, Cu, Cd and Pb originate from anthropogenic activities (e.g., industrial activities, traffic, urban and industrial waste disposal sites). Human health risk assessment shows the non-carcinogenic risk of Pb through ingestion for children in some sampling stations. The carcinogenic risk of Cr and Ni in the soils of the study area is higher than the acceptable value (1×10-4) for children through the ingestion route. The results of this study highlight the necessity of environmental management of human activities (traffic, agriculture, and industries) to reduce the negative consequences of potentially toxic elements intake by residents of the study area. https://gnf.khu.ac.ir/article_4122.html The refraction method is a highly efficient and accurate tool for determining the condition of subsurface layers and is therefore of great importance. The more accurately the first-arrival times are picked in data acquired by this method, the more complete the interpretation will be, and consequently, better information can be obtained. In general, the quality of first arrivals depends on near-surface structure, source type, and the signal-to-noise ratio. Therefore, if the near-surface layering is complex or the signal-to-noise ratio is low, automatic picking of first-arrival times becomes a challenging task. In this study, automatic algorithms and techniques are used to pick first-arrival times in both minimum-phase and zero-phase data. The algorithms developed for minimum-phase data are based on the fact that the transition between noise and signal-contaminated noise can be automatically detected by identifying sudden changes in any of the proposed attributes, including energy ratio, entropy, or fractal dimension. These techniques perform calculations using moving windows along the seismic trace. In addition, the use of a suitable edge-preserving smoothing (EPS) indicator enhances the clarity of these sudden changes, leading to more accurate detection of the onset of first-arrival times. The techniques applied to zero-phase data (considering the difference in the onset of first arrivals compared to minimum-phase data) are based on the application of three attributes: trace energy, entropy, and fractal dimension. If the noise level in the data is very high such that the algorithm fails to detect the first-arrival time, an incorrect pick may occur. In such cases, the picked times are corrected using interpolation from the neighboring preceding and following traces. It should be noted that these attributes were applied to both synthetic and real data, yielding accurate and reliable results for both minimum-phase and zero-phase datasets. https://gnf.khu.ac.ir/article_11696.html Mineral prospectivity mapping, as a key tool in mineral exploration, faces challenges such as complex nonlinear relationships, data heterogeneity, and the limitations of labeled datasets. In this study, an unsupervised hybrid deep learning approach based on a Long Short-Term Memory (LSTM) network is proposed to identify prospective mineralization zones. The proposed model is designed to hidden structures, similarities, and anomalies in geoscientific data without requiring labeled training samples. Initially, the dataset is automatically grouped using statistical and algorithmic criteria, after which targets with the highest mineral prospect are delineated using a confidence index. To evaluate the effectiveness of the proposed approach, the model was applied to the 1:100,000 Kajan sheet in Isfahan Province, Iran, an area with significant Cu–Au mineralization potential. The input data include alteration, geochemical, fault, and intrusive rock, which were transformed using fuzzy logic prior to being fed into the deep learning framework. The results demonstrate that the proposed model is capable of capturing complex patterns and effectively delineating prospective zones, with outputs showing strong spatial consistency with known geological features. Compared to conventional deep learning techniques, the proposed method offers notable advantages by eliminating the need for labeled data and enhancing the modeling of nonlinear relationships. Overall, the findings suggest that unsupervised deep learning models, particularly those based on LSTM architectures, provide a robust and efficient framework for mineral prospectivity mapping and can significantly support decision-making in mineral exploration https://gnf.khu.ac.ir/article_11697.html The collision between the Arabian and Eurasian plates is one of the key processes for understanding the evolution of the central segment of the Alpine–Himalayan belt. The development of the tectono-sedimentary systems of Zagros, Alborz, Talesh, and the Greater and Lesser Caucasus belts, as well as the depositional basins of the South Caspian, Moghan-Kura, and Central Iran, is fundamentally linked to this event. In addition to producing significant structural and tectonic changes at the regional scale, this collision led to major transformations in depositional patterns and in the evolution of back-arc and foreland basins. Among the most prominent indicators of this transition are the unconformities recorded in stratigraphic successions. These unconformities reflect processes such as pulsed uplift, abrupt changes in depositional regimes, variations in sedimentation rate, the influx of large volumes of clastic material, and short- to long-term interruptions in sedimentation. Numerous lines of evidence and previous investigations in the Zagros, Alborz, Talesh, and Caucasus belts show that the timing and characteristics of these unconformities are asynchronous and directly tied to the local dynamic of the orogenic belt. In the Moghan and South Caspian basins, the transition from deep-marine deposits to deltaic and continental units is accompanied by a marked increase in sedimentation rate, and the appearance of regional unconformities attests to the onset of the collisional phase and the associated mountain building. Correlation of unconformities across structural–sedimentary domains indicates that although the precise timing of events may differ slightly, a general pattern of progressively intensifying orogeny from the Eocene–Oligocene toward the Middle Miocene, and its culmination in the Pliocene–Quaternary, is evident throughout these mountain belts in association with the closure of the Neo-Tethys Ocean. https://gnf.khu.ac.ir/article_11698.html The Kordkandi deposit is located 26 km northwest of Zanjan, within the Western Alborz-Azarbaijan zone and the Tarom subzone, occurring as a stratabound mineralization within Eocene andesitic basalt lava flow units (equivalent to the Karaj Formation). Copper mineralization in this deposit is primarily observed as sulfide minerals including chalcopyrite, bornite, chalcocite, and lesser pyrite and specular hematite exhibiting disseminated, vein-veinlet, and replacement textures. The volcanic rocks in this area were formed in an extensional, back-arc environment. Geochemically, the investigated samples fall within the calc-alkaline to high-potassium calc-alkaline to shoshonitic series. Based on the host rock characteristics, mineralogy, texture and structure, geometry, and alteration, this deposit shows significant similarity to Manto-type deposits in Chile. According to these lines of evidence, it can be stated that the Kordkandi copper deposit formed during burial metamorphism stages within andesitic basalt units. During this stage, with increasing burial depth, copper mineralization occurred alongside alterations such as zeolitization, chloritization, epidotization, silicification, and carbonatization. Subsequently, due to the uplift of the area and through weathering and supergene processes, secondary minerals were formed in this deposit. https://gnf.khu.ac.ir/article_11699.html Understanding groundwater chemistry and quality in karst aquifers is essential for sustainable water-resource management because of geological and hydrogeochemical heterogeneity. This study aimed to investigate the hydrogeochemistry of karst aquifers in Lorestan Province and identify the processes controlling groundwater chemistry. For this purpose, water samples were collected from ten springs and three wells during three sampling periods from 2021 to 2023 and analyzed for physicochemical parameters, major ions, trace elements, and metals. The data were interpreted using hydrochemical diagrams, ionic ratios, saturation indices, and multivariate statistical analyses, including hierarchical cluster analysis, fuzzy clustering, principal component analysis, and principal component analysis based on centered log-ratio transformation. The results showed that groundwater samples can be divided into four hydrochemical groups, A, B, C, and D. Groups B and C showed a calcium–magnesium pattern with bicarbonate dominance, indicating carbonate control and water–rock interaction. Group A had a more mixed composition with relative enrichment in sulfate and chloride and was influenced by mineral dissolution, limited mixing, and local geochemical conditions. In contrast, Group D was distinguished from the other groups by Na–Cl facies, high EC, different ionic composition, and low Br/Cl, Li/Cl, Sr/Cl, and Ba/Cl ratios, indicating the influence of evaporitic units, particularly the Gachsaran Formation. Samples S2 and S3, with increased SO₄, Cl, and Na, highlighted the role of gypsum, halite, and evaporitic components, whereas S1, S6, S7, and P3 showed intermediate or mixed behavior. The statistical analyses showed that hydrochemical boundaries between some groups are gradual and that not all samples are completely separated. Trace-element ratios were also useful for interpreting local geochemical differences and identifying distinct samples. Overall, the integration of major ions, trace-element ratios, saturation indices, and statistical analyses provided a process-based framework for differentiating hydrochemical patterns and interpreting groundwater chemistry variations in the karst–structural aquifer of Lorestan Province. https://gnf.khu.ac.ir/article_11700.html Sudden groundwater inflow into open‑pit mines can create significant technical, safety, and economic challenges, especially in mining areas where comprehensive hydrogeological investigations have not been conducted prior to development. The Mehdiabad Pb–Zn mine, one of the largest metallic deposits in Iran, has recently experienced groundwater inflow through the pit floor, despite the absence of detailed prior groundwater studies in the region. This study aims to determine the origin, flow pathways, and hydraulic connectivity of groundwater entering the open-pit by using an integrated approach that combines groundwater‑potential mapping, hydrochemical analyses, and stable‑isotope investigations. Groundwater potential zoning in karstified carbonate formations was performed by integrating seven controlling factors—lithology, annual precipitation, distance to faults, lineament density, vegetation cover, elevation, and slope—within a GIS environment using the Analytical Hierarchy Process (AHP). The results indicate that carbonate formations intersected by major structural features exhibit the highest groundwater potential and spatially coincide with the location of the open pit. Hydrochemical analyses reveal a dominant Ca–Mg–HCO₃ water type, indicating that carbonate dissolution is the primary process governing groundwater chemistry. Saturation indices calculated using PHREEQC show that the waters are at equilibrium to supersaturated with respect to calcite and dolomite. Stable‑isotope compositions (δ¹⁸O and δ²H) suggest a modern meteoric origin and demonstrate strong hydraulic connectivity between the pit water and the surrounding groundwater system. Integrating spatial, hydrochemical, and isotopic evidence supports the development of a conceptual hydrogeological model in which a fault‑controlled karst system directs groundwater flow toward the open pit. The findings provide a solid scientific basis for groundwater management and inflow‑control strategies in the Mehdiabad mine and other large open‑pit mines situated in karst environments. https://gnf.khu.ac.ir/article_11701.html Rare earth elements (REEs), as powerful geochemical tracers, are effective tools for distinguishing sedimentary and hydrothermal origins in surface environments. In this study, the origin of soils and river sediments in the Kooh-Sorkh area (northeast Iran), which formed in sedimentary rocks but have been affected by argillic hydrothermal alteration, has been investigated. A total of 30 samples, including 26 soil samples and 4 river sediment samples, were analyzed using ICP MS. The REE data were normalized to Post Archean Australian Shale (PAAS), chondrite and Primitive Mantle (PM). Key geochemical indices, including (La/Yb)ₙ, (La/Sm)ₙ, Eu/Eu*, Ce/Ce*, and (Gd/Yb)ₙ, were calculated. Additionally, high field strength elements (HFSE) such as Zr, Ti, and Nb were used to determine the origin. All three normalization methods show enrichment of light rare earth elements (LREE), a positive Eu anomaly, a slightly negative Ce anomaly, and a negative Gd anomaly. HFSE ratios indicate a limited contribution from sedimentary sources to pedogenesis and confirm the influence of an external hydrothermal origin. The La, Th, Sc ternary diagram place most samples out of the sedimentary origin field but closed to basic magma sources, which clearly distinguishes them from materials of pure sedimentary origin. Overall, the REE patterns provide strong evidence of hydrothermal processes related to epithermal systems in the region. https://gnf.khu.ac.ir/article_11718.html The investigation of hydrogeochemical evolution of hot springs through water-rock interaction identifies flow pathways, dissolution, ion exchange, and water quality. This study examines the chemistry of hot and cold karstic springs in the Allah Akbar heights of Dargaz to determine their origin and geochemical evolution. Rock samples from the Tirgan Formation and travertines were collected, and thin sections were studied for facies and diagenetic history. In two seasons (2023), ten water samples were taken from the springs, and parameters (T, pH, EC, Eh, TDS, DO) and major ions were measured. Thin sections revealed a dual-porosity system in the Tirgan Formation, which, by increasing water-rock contact, played a direct role in enriching water with Ca²⁺ and HCO₃⁻ and forming travertine around hot springs. Quaternary travertines along active faults indicate the continuation of these processes. Cold spring temperatures ranged 15.6–19.4°C, hot springs up to 32.2°C, and EC between 256–1022 µS/cm. Data were processed using Piper, Gibbs, Schoeller, Wilcox, SI, and Eh-pH diagrams. Results show that hot spring evolution results from lithology (Tirgan Formation), diagenesis (dissolution and dual porosity), and tectonics. Hot springs are of Ca-HCO₃ type with a common origin, while Chelmir is of sulfate type. According to Gibbs, carbonate weathering is the main factor controlling water chemistry, and SI confirms supersaturation with respect to calcite and dolomite. Most springs have "good to acceptable" drinking water quality and fall into class C3-S1 for irrigation. This study clarifies the role of diagenesis and dual porosity in the evolution of the Tirgan aquifer and reveals the geotourism potential of the hot springs.