Groundwater for Sustainable Development最新文献

{"title":"Hybrid machine learning for predicting groundwater level: A comparison of boosting algorithms with neural networks","authors":"Milad Barzegar ,&nbsp;Saba Gharehdash ,&nbsp;Faysal Chowdhury ,&nbsp;Ming Liu ,&nbsp;Wendy Timms","doi":"10.1016/j.gsd.2025.101508","DOIUrl":"10.1016/j.gsd.2025.101508","url":null,"abstract":"<div><div>This study proposes a novel hybrid machine learning framework that integrates gradient boosting (XGBoost, LGBM) and neural network models (LSTM, MLP) with Basin Hopping Optimization (BHO) to improve groundwater level forecasting. The approach simultaneously optimizes input lag times and model hyperparameters, addressing a key limitation in previous studies. Four hybrid models (XGBoost-BHO, LGBM-BHO, LSTM-BHO, MLP-BHO) are evaluated for daily one-to seven-day-ahead predictions, incorporating meteorological inputs. Results showed that all models achieved high predictive accuracy (R² &gt; 0.98), with LSTM-BHO yielding the lowest MAE and RMSE across both boreholes. Boosting models, particularly XGBoost-BHO, demonstrated strong short-term performance with narrow residual distributions and significantly lower computation time. These findings highlight the effectiveness of combining machine learning and metaheuristic optimization for robust groundwater forecasting.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101508"},"PeriodicalIF":4.9,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144926193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preventing lead (Pb) contamination in rural community water systems in LMICs through analytical screening, policy and standards enforcement, and supply chain interventions","authors":"Siddhartha Roy ,&nbsp;Michael B. Fisher ,&nbsp;Solomon Minyila ,&nbsp;Zakaria Seidu ,&nbsp;Kaida Liang ,&nbsp;Aaron A. Salzberg","doi":"10.1016/j.gsd.2025.101509","DOIUrl":"10.1016/j.gsd.2025.101509","url":null,"abstract":"<div><div>Lead (Pb) is a neurotoxic metal that can leach into potable water from plumbing components. This study investigated Pb contamination in rural community water systems in Ghana to inform strategies for reducing its occurrence in low- and middle-income countries (LMICs). We screened 101 systems, including 83 borehole handpumps and 17 mechanized piped systems, installed across seven districts during 2019–22, using a handheld X-Ray Fluorescence (XRF) analyzer. Despite manufacturer assurances that components were lead-free, 57 % of tanks in borehole handpumps and 100 % of taps in mechanized systems exceeded the international “lead-free” standard of 0.25 % Pb w/w. Other components like riser pipes, rods, cylinders, and foot valves generally met standards. There were no significant differences in Pb content (p &gt; 0.05) for systems across districts or installation years. Consequently, we engaged original equipment manufacturers (OEMs) to source truly lead-free alternatives. Stainless steel taps from one manufacturer replaced leaded brass taps, and a second manufacturer custom-fabricated stainless steel handpump tanks and spouts to replace lead-containing galvanized steel components. These were verified lead-free via XRF before installation. Despite initial claims from multiple OEMs that sourcing lead-free components would be prohibitively difficult or expensive, the switch was logistically feasible and increased overall installation costs by only 2 % or less. Our findings highlight vulnerabilities in global plumbing supply chains and manufacturing practices that can introduce Pb and harm consumers, and illustrate the value of independently verifying OEM assurances and specifications for lead-free components. We offer guidance for implementers to mitigate water Pb contamination, with some measures also limiting iron corrosion-related system failures. This includes adherence to product quality standards, analytical screening considerations, supply chain interventions, water quality monitoring, and progressive remediation of existing systems. This case study suggests that eliminating Pb from rural water systems is feasible and cost-effective in Ghana and other LMIC settings.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101509"},"PeriodicalIF":4.9,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144917545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neutralization of pH and removal of heavy metals from acid mine water by using low-cost biosorbents in batch and column studies","authors":"Fida Hussain ,&nbsp;Lan Hee Kim ,&nbsp;Sang-Eun Oh ,&nbsp;Sungpyo Kim","doi":"10.1016/j.gsd.2025.101506","DOIUrl":"10.1016/j.gsd.2025.101506","url":null,"abstract":"<div><div>The present research explored raw oyster shell (RO), oyster shell biochar (OB), and ginkgo leaves biochar (LB) as low-cost biosorbents for heavy metal removal and pH neutralization from acid mine water. Five adsorbents were tested in batch mode. The results showed that OB, RO, and LB effectively removed Cd²⁺ (57–98 %), Cu²⁺ (93–99 %), and Fe²⁺ (96–99 %), while Mn²⁺ (7–57 %) and Zn²⁺ (18–97 %) exhibited lower removal efficiencies. RO and OB also increased solution pH to ∼6.3 due to their alkaline buffering capacity. LB, OB, and RO were further tested in series columns. RO and OB with 31.1, 93.5, and 185 min HRTs were tested in primary columns. A hybrid column with LB, OB, and RO was tested at 93.5 min HRT to enhance removal efficiency. Increasing HRT improved both metal removal and breakthrough times. RO and OB with 185 min HRT removed ∼71 % Cd²⁺, ∼93 % Cu²⁺, ∼6 % Mn²⁺, ∼52 % Fe²⁺, and ∼11 % Zn²⁺ from the primary column. In the secondary hybrid column, 99.53 % Cd²⁺, 100 % Cu²⁺, 55.20 % Mn²⁺, 100 % Fe²⁺, and 74.03 % Zn²⁺ were removed. Cu²⁺ &gt; Fe²⁺ &gt; Cd²⁺&gt; Zn²⁺&gt; Mn²⁺ was the column mode metal removal order. The columns' pH profiles changed significantly during metal sorption, suggesting buffering processes and acidic metal ion elimination. Column modeling using Thomas and Yoon–Nelson equations confirmed high adsorption capacities and extended breakthrough times, particularly in the hybrid system. Mechanistic analysis via SEM–EDS revealed surface deposition and co-precipitation of Cd²⁺, Cu²⁺, and Fe²⁺ on RO and OB, while FTIR spectra and XRD patterns confirmed the roles of carbonate, hydroxyl, phosphate, and amine groups in metal binding. LB's porous structure and functional groups enhanced Mn²⁺ and Zn²⁺ removal through complexation and diffusion-driven sorption. The findings support the potential of oyster shell-based composites as sustainable biosorbents for the remediation of metal-contaminated, acid mine water, and highlight future opportunities for optimization through surface functionalization and hybrid treatment designs.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101506"},"PeriodicalIF":4.9,"publicationDate":"2025-08-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144903717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integration of hydrogeophysical and remote sensing data for enhanced groundwater potential mapping in fractured limestone aquifers: A case study in southeast Beni Suef, Egypt","authors":"Hakeem Musaed ,&nbsp;Khaled Gemail ,&nbsp;Sayed Bedair ,&nbsp;Mohamed El Alfy","doi":"10.1016/j.gsd.2025.101507","DOIUrl":"10.1016/j.gsd.2025.101507","url":null,"abstract":"<div><div>Identifying groundwater potential zones in arid regions is crucial in mitigating depletion and enhancing the sustainability of water resources and food security. To develop an effective groundwater management framework for fractured aquifers in these regions, a thorough understanding of the site's conceptual flow model is crucial for ensuring irrigation water sustainability. It is essential to discern the groundwater potential zones (GWPZs) that have a high likelihood of accessing groundwater resources. This study aims to establish an integrated framework for mapping GWPZs in fractured limestone aquifers by capitalizing on remote sensing (RS) and surficial Direct Current (DC) resistivity data within a Geographic Information System (GIS) environment. By harmonizing surface (precipitation rates, lineament density, watershed, drainage system, land use) and hydrogeophysical data (layer thicknesses, aquifer resistivity, overburden infiltration capacity, and buried geologic structures), this holistic approach aspires to enhance the understanding of hydrogeological frameworks in limestone aquifers, encompassing geological features, hydrological pathways, and hydraulic properties. Focused on the southeastern Beni Suef area, the current findings pinpoint groundwater zones and provide insights into groundwater movement and recharge mechanisms. The area highly suitable for artificial recharge spans 53.71 km² (41 %), whereas the good and low-suitability zones cover 29.98 km² (23 %) and 43.30 km² (33 %), respectively. The resulting framework exhibits potential for broader applications in analogous arid regions, streamlining groundwater exploration, fostering artificial recharge strategies, and promoting sustainable water resource management practices on a global scale. Ultimately, this research not only aids local decision-makers in optimizing groundwater use but also contributes to international efforts to achieve sustainable development goals related to water security and environmental resilience.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101507"},"PeriodicalIF":4.9,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144895954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative study of hydrochemical and machine learning methods for Fe anomaly identification and NBLs estimation in shallow groundwater of representative hydrogeological units in the North China plain","authors":"Nini Li ,&nbsp;Jiangtao He ,&nbsp;Baonan He ,&nbsp;Yanjia Chu ,&nbsp;Zhen Chen","doi":"10.1016/j.gsd.2025.101505","DOIUrl":"10.1016/j.gsd.2025.101505","url":null,"abstract":"<div><div>Iron (Fe) in groundwater results from both natural sedimentation and human activities, impacting biogeochemical cycles and the migration of various components. Increased human activities have disrupted Fe concentrations, causing deviations from the natural state. Thus, identifying Fe anomalies and determining its natural background levels (NBLs) are crucial. In this study, based on subdivided NBLs units, four typical units were selected for anomaly identification using Iterative 2-Sigma method, modified hydrochemical method (MI-OPT), and Isolation Forest model. The results showed that the MI-OPT method showed stable performance and also identified anomalies related to hydrochemical indicators. The Isolation Forest model efficiently detected Fe anomalies through a machine learning-based partitioning approach. In contrast, the Iterative 2-Sigma method exhibited instability due to its dependence on data distribution. Based on the distribution characteristics of the remaining data, the anomaly identification results from the MI-OPT method were selected as the final reference for determining the NBLs of Fe in the four units, with the upper limits being 0.45 mg/L, 2.80 mg/L, 2.58 mg/L, and 1.59 mg/L, progressively transitioning from the recharge area to the runoff and discharge areas. Additionally, an integrated analysis incorporating information entropy, PPI values, and environmental pollution source data explained most of the detected anomalies, validating the reliability of the anomaly identification results. The methods and results presented in this study offer a new perspective on Fe anomaly identification in groundwater.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101505"},"PeriodicalIF":4.9,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144864074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Delineation of groundwater potential zones in hard rock terrains using geospatial techniques and AHP method: A case study from Notse, southern Togo, West Africa","authors":"Komlavi Eyram Agbotsou ,&nbsp;Ayyagari Venkata Surya Satya Anand ,&nbsp;Mozimwè Ani ,&nbsp;Bendalam Moulika ,&nbsp;Edupuganti Naga Dhanamjaya Rao ,&nbsp;Kissao Gnandi","doi":"10.1016/j.gsd.2025.101503","DOIUrl":"10.1016/j.gsd.2025.101503","url":null,"abstract":"<div><div>Groundwater is essential for human survival and sustainable development. While surface water studies are well documented, knowledge of groundwater resources remains limited. Identifying groundwater potential is key to meeting current and future water demands. This study applied geospatial techniques and the AHP method to delineate groundwater potential zones. Twelve thematic layers were integrated: geomorphology, lithology, slope, lineament density, drainage density, rainfall, distance from rivers, topographic wetness index (TWI), soil type, land use land cover (LULC), curvature and elevation. Results indicate that 66.02 % of the study area has low groundwater potential, 33.94 % has moderate potential and only 0.04 % is classified as high potential. Map-removal and single-parameters sensitivity analyses confirm the stability of the AHP model. Validation using borehole data and the ROC curve analysis confirms strong agreement (90 % and 87.5 %) with the predicted zones, demonstrating the model’s reliability for groundwater potential assessment in Notse. These findings offer a scientific foundation for developing sustainable groundwater management strategies, aligned with Sustainable Development Goals (SDG) 2 and 6</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101503"},"PeriodicalIF":4.9,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144864071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anti-passivation Fe-Ni Foam@AC PRB: Coupling bimetallic electron transfer and functionalized adsorption for sustainable groundwater nitrate remediation","authors":"Guangming Li ,&nbsp;Jiani Fu ,&nbsp;Xiaomin Fu ,&nbsp;Shuwen Zhu ,&nbsp;Jie Dong ,&nbsp;Wenpeng Jiang","doi":"10.1016/j.gsd.2025.101504","DOIUrl":"10.1016/j.gsd.2025.101504","url":null,"abstract":"<div><div>This study introduces a novel anti-passivation composite filler, iron-nickel foam@activated carbon (denoted as INF@AC hereafter), tailored for permeable reactive barriers (PRBs) to combat nitrate contamination in groundwater. Through systematic batch and column experiments, the optimal INF/AC mass ratio (2:2) achieved 43.23 % nitrate removal efficiency within 120 min under neutral pH conditions, with chloride ions exhibiting the strongest inhibitory effect (removal efficiency reduced by 21.5 %). The 12-day column experiments further confirmed the system's robustness, showing near-complete nitrate conversion (99.90–99.98 %) and nitrogen selectivity exceeding 95 %. Advanced characterization (XRD, XPS, FT-IR) revealed that AC mitigated INF surface passivation by forming Fe³⁺-O-C interfacial bonds, while Ni²⁺ facilitated electron transfer. Kinetic and XPS data further suggest a reactive hydrogen intermediate (H∗)-mediated pathway, which suppresses byproducts and explains the high selectivity—consistent with iron corrosion electrochemistry. This work establishes a synergistic mechanism (passivation mitigation, electron transfer, H∗-regulated redox), providing a scalable solution for sustainable groundwater remediation.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101504"},"PeriodicalIF":4.9,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144851876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Managed aquifer recharge implementation challenges: Lessons from Chile's water-scarce regions","authors":"Rayen Rivera-Vidal ,&nbsp;José Luis Arumí ,&nbsp;Ovidio Melo ,&nbsp;Verónica Delgado ,&nbsp;Víctor Parra ,&nbsp;Alejandra Stehr ,&nbsp;Linda Daniele","doi":"10.1016/j.gsd.2025.101502","DOIUrl":"10.1016/j.gsd.2025.101502","url":null,"abstract":"<div><div>As water scarcity intensifies globally due to climate change and growing demand, Managed Aquifer Recharge (MAR) is increasingly recognized as a vital nature-based strategy for sustainable groundwater management. Yet, its implementation remains insufficiently adopted in many water-stressed regions. This study addresses the critical gap in understanding the socio-technical and institutional barriers that hinder the widespread adoption of MAR, focusing on Chile—one of Latin America's most water-stressed country. A mixed-methods approach was employed, integrating qualitative policy analysis, quantitative case study evaluations, and a semi-systematic review of 70 international publications. Key findings reveal persistent challenges, including limited hydrogeological data, weak institutional coordination and lack of clear quality standards. The 15 MAR initiatives analyzed in Chile show wide variation in design, scale, and implementation context. Success often depends on local hydrogeological knowledge, active involvement from water users and sustained institutional support. International case studies illustrate that, while some challenges are highly context-specific, others—such as low public awareness, regulatory gaps regarding water reuse, and insufficient monitoring—are widespread across diverse geographic and institutional settings. This study provides a comprehensive framework for overcoming barriers to MAR implementation, highlighting the importance of adaptive legal frameworks, scientific monitoring and proactive stakeholder engagement. Based on Chilean and international experience, the study proposes a sequenced set of short-, medium-, and long-term policy recommendations to guide MAR development. The insights gained offer valuable guidance for countries worldwide seeking to enhance water security through strategic groundwater management. Future research should focus on developing adaptive governance models and mechanisms for sustained stakeholder collaboration.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101502"},"PeriodicalIF":4.9,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144860937","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of Ti contamination and transport mechanisms in ferruginous soils: Impacts of ilmenite and rutile processing and immobilization using clay amendments","authors":"B. Bincy,&nbsp;C.P. Devatha,&nbsp;Arun Kumar Thalla","doi":"10.1016/j.gsd.2025.101499","DOIUrl":"10.1016/j.gsd.2025.101499","url":null,"abstract":"<div><div>Titanium (Ti) contamination from coastal mining activities poses significant threats to groundwater and soil quality, especially in regions with ferruginous soils (FS). This study investigates Ti transport and immobilization in FS, assessing its natural retention capacity and the enhancement achieved using bentonite, zeolite, and kaolinite amendments. Environmental assessment identified industrial discharge as the primary source, with elevated Ti in soil (271.67 ppm), surface water (0.56 ppm), and groundwater (0.45 ppm), forcing 86 % of households to rely on alternative sources. The 3D flow model demonstrated that FS reduces Ti mobility; however, rising inlet to outlet head differences (6-12 cm) led to increased flow rates (0.1–0.7 cm³/min), resulting in elevated Ti concentrations in wells 2 and 3(8.55 ppm and 7.23 ppm). Ti peaks observed in the wells were the result of desorption following initial adsorption, reflecting the breakthrough pattern. Batch adsorption tests (0–1000 ppm Ti, 25–27 °C, 1:20 ratio, pH-3.9-5.5) revealed chemisorption dominance at low concentrations (K_d = 28.5 L/kg, K_L = 33.39 L/kg) and multilayer physisorption at higher loads (q_m = 11.09 mg/g, K_f = 88.11 L/kg), modelled using Linear, Langmuir, and Freundlich isotherms. XRD and SEM-EDS confirmed Ti incorporation into stable mineral phases (Al₈Ti₃₂Cl₄₈, Fe₄Ti₂Cl₇, Ti₃O₅) with increased retention (4.1–7.8 %). Among amendments, bentonite-enhanced FS showed the highest Ti retention (97.5 %, K_f = 478.5 L/kg) at 10–20 % dosage. This integrated experimental framework is transferable to other heavy metal-affected coastal aquifers, where it supports predictive contaminant transport and groundwater protection strategies aligned with the Sustainable Development Goals.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"30 ","pages":"Article 101499"},"PeriodicalIF":4.9,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144758059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Origin of lithium-rich deep formation waters in Upper Devonian – Lower Carboniferous sediments of Shu-Sarysu gas fields, Kazakhstan, studied by hydro-chemical modeling","authors":"Malis Absametov ,&nbsp;Daniyar Chensizbayev ,&nbsp;Nurbol Itemen ,&nbsp;Ermek Murtazin ,&nbsp;Vladimir Mirlas ,&nbsp;Michael Zilberbrand ,&nbsp;Yaakov Anker","doi":"10.1016/j.gsd.2025.101500","DOIUrl":"10.1016/j.gsd.2025.101500","url":null,"abstract":"<div><div>This study analyses the origin of the deep, highly mineralized artesian groundwater of the Shu-Sarysu gas fields based on hydro-chemical modeling. Owing to the local geology these Na-Ca-Cl and Ca-Na-Cl brines contain lithium and other rare metals in concentrations suitable for industrial extraction. Once brine compositions were chemically characterized and their origin studied, three brine formation scenarios were considered: evaporation of the ancient seawater, dissolution of evaporates by ancient seawater, and dissolution of evaporates by fresh water. Following the inverse PHREEQC modeling, the main processes forming calcium-chloride and sodium-calcium-chloride composition of the brines are the dissolution of evaporites by ancient seawater or by freshwater, dolomitization<strong>,</strong> gypsum and halite dissolution, sulfate reduction and cation exchange with clayey material. Water-rock interaction is suggested to be the main lithium enrichment process.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"30 ","pages":"Article 101500"},"PeriodicalIF":4.9,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144763931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}