Groundwater for Sustainable Development最新文献

{"title":"Misiones lateritic soil as a safely disposable, single-use adsorbent for arsenate removal","authors":"R. Boglione ,&nbsp;M.C. Panigatti ,&nbsp;C. Griffa ,&nbsp;S. Keller ,&nbsp;M.C. Schierano ,&nbsp;M. Asforno ,&nbsp;M. Farías ,&nbsp;F.D. Reina ,&nbsp;E.B. Halac ,&nbsp;A.L. Marzocca ,&nbsp;P.N. Alderete ,&nbsp;P.C.V. Sánchez ,&nbsp;E.G. De Seta ,&nbsp;J.M. Meichtry","doi":"10.1016/j.gsd.2025.101535","DOIUrl":"10.1016/j.gsd.2025.101535","url":null,"abstract":"<div><div>Lateritic soil (LS) from Misiones province, Argentina, was evaluated as a single-use, safely disposable adsorbent for pentavalent arsenic (As(V)) removal on three different systems:1) synthetic solutions at [As(V)]₀ ≤ 10 mg L⁻¹ and pH 6.5 (LSL); 2) synthetic solutions at [As(V)]₀ ≤ 50 mg L⁻¹ and pH 2 (LSH); and 3) three different groundwaters obtained nearby Rafaela city (Santa Fe, Argentina), with [As(V)]₀ ≤ 0.165 mg L⁻¹ and 7 &lt; pH &lt; 8 (LSR). Adsorption equilibrium followed the Langmuir isotherm, with <em>q</em>_max = 0.44 mg As g⁻¹ and <em>K</em>_L = 51 mg⁻¹ L for LSL, and <em>q</em>_max = 2.1 mg As g⁻¹ and <em>K</em>_L = 0.6 mg⁻¹ L mg for LSH. In LSR, an up to 47 times decrease in adsorbed As(V) (<em>q</em>_e) was observed, attributable to the presence of interfering ions. Desorption with 0.10 M hydrochloric acid (HCl), acetic acid (HAc) and sodium hydroxide (NaOH) showed that NaOH achieved over 72 % As(V) release, while with HAc and HCl was &lt;10 %, indicating near irreversible adsorption. As(V) concentrations in HCl and HAc leachates from LSL and LSR remained below the 1 mg L⁻¹ limit for hazardous waste; for LSH, this limit was surpassed. Kinetic experiments with LSL showed that, after 1 h, desorbed As(V) peaked to 0.2 and 0.07 mg L⁻¹ for HCl and HAc, respectively, followed by gradual re-adsorption onto precipitated iron oxy-hydroxides until [As(V)] ≤ 0.06 mg L⁻¹ after 24 h. These results support the suitability of LS as a single-use, safely disposable adsorbent for treating waters with low As(V) concentrations.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101535"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145319488","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":"Treatment of fluoride-contaminated water using hydrous Mn and Zr oxide doped hybrid anion exchange resin (HAIX/Mn-Zr)","authors":"Jay Sharma,&nbsp;Vikrant Ranyal,&nbsp;Sudipta Sarkar","doi":"10.1016/j.gsd.2025.101534","DOIUrl":"10.1016/j.gsd.2025.101534","url":null,"abstract":"<div><div>Fluoride contamination of groundwater is a persistent problem in the Indian Peninsula and also in many parts of the world. Zirconium oxide-impregnated polymers have demonstrated promising fluoride removal capacity; however, their restricted operating range of pH and interference from co-existing anions invariably limit the feasibility of field application. To obviate the problem, a strong-base polymeric anion exchanger (INDION 830S) was modified with the impregnation of dual metal (Zr and Mn) hydroxide nanoparticles. The synthesized resin (HAIX/Mn-Zr) demonstrated preferential fluoride capture in the presence of competing anions in the pH range of 4.5–5, with the point of zero charge measured at pH around 5.1 and a good removal efficiency of 80.7 % up to pH 6.0. Adsorption of fluoride by HAIX/Mn-Zr followed the Freundlich isotherm model and the pseudo-second-order kinetics. The maximum fluoride adsorption capacity was 28.1, 29.7, and 31.5 mg/g at 20, 30, and 40 °C temperatures, respectively. The adsorption process was endothermic, exhibiting an activation energy of 12.61 kJ/mol, a negative Gibbs free energy, and a positive enthalpy change. Fourier-transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) analysis indicated chemisorption of fluoride onto HAIX/Mn-Zr, while X-ray diffraction (XRD) confirmed its amorphous structure. Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDS) revealed a visible morphology change after the loading of Mn (2.2 wt%) and Zr (21.8 wt%). The column study demonstrated that around 2000 bed volumes of contaminated water were treated before the breakthrough of 1.5 mg/L of fluoride. Overall, the HAIX/Mn-Zr is a low-cost sorbent with a facile synthesis and regeneration procedure, reusability up to five cycles, and high fluoride removal efficiency, indicating its high potential for the defluoridation of contaminated groundwater.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101534"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145319489","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":"A triple-benefit approach: Simultaneous removal of nitrate and emerging contaminants from groundwater using an integrated electrocoagulation-adsorption system and in-situ PAC separation","authors":"Fatemeh Ahmadi ,&nbsp;Ehsan Ranjbar ,&nbsp;Majid Baghdadi ,&nbsp;Shima Mardani ,&nbsp;Behnoush Aminzadeh Goharrizi","doi":"10.1016/j.gsd.2025.101532","DOIUrl":"10.1016/j.gsd.2025.101532","url":null,"abstract":"<div><div>The simultaneous presence of organic and inorganic contaminants in the environment is a global concern. These contaminants penetrate the soil and gradually leach into groundwater, posing substantial environmental and human health hazards. This study evaluates the efficiency of a combined electrocoagulation-adsorption system for the simultaneous removal of nitrate (NO₃⁻) and contaminants of emerging concern (CECs). The study examined how operational parameters including electrode materials, current, adsorbent dosage and reaction time affect the simultaneous removal of NO₃⁻ and bisphenol A (as a model CEC) from groundwater. The optimal conditions were obtained with an Al anode and Cu foam cathode, current of 0.3 A, reaction time of 60 min, and powdered activated carbon (PAC) dosage of 120 mg/L. Under these conditions, NO₃⁻ and bisphenol A removal reached 94% and 89%, respectively. Mechanistically, electrocoagulation facilitated both contaminant removal and independent precipitation of PAC, therefore there is no need for additional steps to separate it from the reactor. These findings highlight the potential of the proposed integrated system as a cost-effective and practical solution for the treatment of contaminated groundwater.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101532"},"PeriodicalIF":4.9,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145320292","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":"Multiple household water sources and uses in rural ASALs: Evidence and proposed solutions from Turkana, Kenya","authors":"Vivian Abungu ,&nbsp;Kofi Adanu ,&nbsp;Mostafa Dadashi Firouzjaei ,&nbsp;Benon Wasonga ,&nbsp;Mark A. Elliott","doi":"10.1016/j.gsd.2025.101531","DOIUrl":"10.1016/j.gsd.2025.101531","url":null,"abstract":"<div><div>Water scarcity remains a pressing issue in arid and semi-arid lands (ASALs), often compelling households to rely on multiple water sources to meet their daily water needs. While widespread in many low and middle-income settings globally, the specific extent and dynamics of this practice remain underexplored. This study addresses this gap by examining multisource water use in Turkana County, a predominantly pastoralist and rural low-income ASAL in Kenya. A cross-sectional survey of 475 households revealed universal reliance on multiple water sources, with usage patterns largely influenced by seasonal availability. Despite operational and water quality constraints, boreholes were the most utilized source, supporting 94.1 % of households. Other prevalent sources included rivers/streams, shallow hand-dug wells on dry riverbeds, water pans, springs, water vendors, and the saline Lake Turkana. Roof-based rainwater harvesting also supported a substantial proportion of households (19.4 %), although it was constrained by housing design. While pronounced disparities in water access were observed between rural townships and more remote areas, statistical analysis revealed significant seasonal associations between water source use and household activities across Turkana. This study proposes implementing alternative rainwater harvesting techniques: macro and rock catchments, and subsurface dams to address water scarcity and flood risk in Turkana. Findings highlight the critical role of multiple water source use in rural low-income ASALs and its potential to inform research, global water management, health outcomes, and resilience-oriented interventions.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101531"},"PeriodicalIF":4.9,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145319491","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":"Uranium in the groundwaters of the Republic of Kazakhstan","authors":"N.A. Medeshova ,&nbsp;D.A. Novikov ,&nbsp;K.O. Zhinak ,&nbsp;A.T. Makyzhanova ,&nbsp;M.R. Zapparov ,&nbsp;A.M. Orynbek ,&nbsp;F.F. Dultsev","doi":"10.1016/j.gsd.2025.101527","DOIUrl":"10.1016/j.gsd.2025.101527","url":null,"abstract":"<div><div>Hydrogeochemical data on uranium content in the groundwaters of Kazakhstan are evaluated and summarized for the first time. Uranium concentrations in the groundwaters of Kazakhstan vary within a broad range; according to our data, this range is 4.8∙10⁻⁶ – 78 mg/l. The regional background uranium concentration for the groundwaters of Kazakhstan is 13 μg/l, and the anomalous level is 17 μg/l. The maximal uranium content (exceeding 10 mg/l) is detected in the acid groundwaters in oxidation zones of uranium deposits (the Kamyshovoye, Viktorovskoye, Bokayskoye, Abayskoye, Dzhusandalinskoye, etc.). Uranium concentration in near-neutral groundwaters of ore-bearing rocks ranges from 0.1 to 10 mg/l. Beyond the boundaries of deposits, uranium concentrations decrease to n∙10⁻¹ mg/l. Under favorable hydrogeochemical conditions, uranium has also been observed to accumulate in groundwaters outside the deposits. In this case, the formation of uranium-containing groundwater is associated with the chemically enhanced transition of uranium from rocks into groundwater and its subsequent accumulation due to complexation processes. An increase in uranium concentration occurs in alkaline waters of HCO₃-Na, HCO₃-Cl-Na, and Cl-HCO₃-(CO₃)-Na composition. With an increase in water salinity to several grams per liter (regardless of its absolute value), uranium concentration rises and can reach n∙10⁻¹ mg/l. With a further increase in groundwater salinity (up to n∙10 g/l), uranium concentration may increase to n∙10 mg/l, which is characteristic of Kazakhstan, with its arid climatic conditions, so that the groundwaters and surface waters are associated with closed depressions as a result of evaporative concentration.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101527"},"PeriodicalIF":4.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265922","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":"The role of clay layers in managing fluid pressure propagation during managed aquifer recharge","authors":"John B. Ogunleye,&nbsp;Ethan W. Conley,&nbsp;Mahesh P. Parija,&nbsp;Ryan M. Pollyea","doi":"10.1016/j.gsd.2025.101529","DOIUrl":"10.1016/j.gsd.2025.101529","url":null,"abstract":"<div><div>Groundwater abstraction in the Potomac aquifer of the Virginia Coastal Plain has caused significant groundwater depletion, saltwater intrusion, and land subsidence. Managed Aquifer Recharge (MAR) is being explored as a mitigation strategy. However, the Potomac Aquifer position above crystalline basement rock raises concerns about induced seismicity due to fluid pressure changes. Existing numerical models often assume homogeneous aquifer properties, overlooking fine heterogeneities. Recent deep drilling efforts for MAR in the Virginia Potomac aquifer reveal 20 m-thick clay interbeds, yet their role in fluid pressure dynamics during high-rate injection remains poorly understood. This study develops a 3D numerical model incorporating aquifer heterogeneity, such as discontinuous clay layers (DCLs), to buffer fluid pressure propagation into deep basement rocks. Results indicate that focusing injection above the clay layer separating the middle and lower Potomac aquifer reduces fluid pressure reaching the basement when lateral DCL dimensions exceed 800 × 400 m. This study also shows that injecting into the upper and middle Potomac aquifer increases fluid pressure within the overlying Potomac confining unit, potentially mitigating land subsidence and reducing pressure propagation toward the basement, which decreases the risk of inducing seismicity.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101529"},"PeriodicalIF":4.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145319492","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":"Spatiotemporal geochemical evolution of groundwater through an open-loop geothermal system – a field pilot study","authors":"Charis Sin-Yee Wong ,&nbsp;Jérôme Comte ,&nbsp;Jasmin Raymond ,&nbsp;Christine Rivard ,&nbsp;Geneviève Bordeleau","doi":"10.1016/j.gsd.2025.101525","DOIUrl":"10.1016/j.gsd.2025.101525","url":null,"abstract":"<div><div>To investigate the operational challenges faced by groundwater heat pump systems (GWHPs), a field pilot study (two heat injection tests, HITs) was conducted to mimic operational processes involving pumping, heating and reinjection into the aquifer to simulate the cooling mode. This study aimed to acquire an understanding of the spatiotemporal evolution of groundwater chemistry as it circulates throughout different parts of the system (pumping well, heater inlet/outlet, injection well, monitoring well downgradient) and during different test phases (pre-test, HITs, post-test recovery). Hierarchical clustering analyses identified six clusters corresponding to different water types through space and time, which were categorised into two main conditions: natural (Na-Ca-Cl water) and perturbed (Ca-mixed-(HCO₃-Cl-SO₄) water). Pumping-induced mixing between shallow and deeper water, along with draw-in of dissolved oxygen (DO), induced oxidising conditions and precipitation of iron oxides in the injection wells, subsequently leading to well blockage and premature termination of both HITs. The chemical signatures of the injected warm water reached the monitoring well faster than the thermal plume, suggesting different heat and solute transport mechanisms at play. While principal component analyses showed that water mixing was the main driver of differences between natural and perturbed geochemical conditions, geochemical modelling confirmed that DO intrusion was the main driver of iron oxide precipitation, surpassing the effect of water mixing and increased temperatures. Results from this study underline the importance of conducting a comprehensive spatiotemporal geochemical assessment of the hydrogeological system prior to and throughout the lifecycle of a GWHP system to predict and manage operational risks.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101525"},"PeriodicalIF":4.9,"publicationDate":"2025-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145320291","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":"RESPONSE OF PINIOS HYDROLOGIC OBSERVATORY (AGIA BASIN-THESSALY, GREECE) TO STORM DANIEL","authors":"Ayesha Nawaz ,&nbsp;Maria Rosaria Alfio ,&nbsp;Konstantinos Babakos ,&nbsp;Anna Chatzi ,&nbsp;Gaetano Daniele Fiorese ,&nbsp;Andreas Panagopoulos ,&nbsp;Vassilios Pisinaras ,&nbsp;Gabriella Balacco","doi":"10.1016/j.gsd.2025.101528","DOIUrl":"10.1016/j.gsd.2025.101528","url":null,"abstract":"<div><div>Extreme weather events are becoming increasingly frequent and intense due to climate change, posing significant challenges to water resource management in vulnerable agricultural regions. Understanding how aquifer systems respond to such events is critical for ensuring long-term groundwater sustainability. Continuous, high-resolution monitoring is essential to capture the dynamics of recharge processes, particularly during intense storms. This study presents novel observations from the Pinios Hydrological Observatory (PHO), located in the Pinios River Basin in Thessaly, Greece one of the country’s most important agricultural areas, heavily dependent on groundwater for irrigation. The PHO, part of the Greek Long-Term Ecological Research Network, is equipped with automated sensors that provided rare, event-scale data during Storm Daniel, a major hydrometeorological event that impacted the region in September 2023. The sensors recorded the passage of the flood wave in near-real time, enabling a detailed analysis of groundwater recharge dynamics. Hourly groundwater level data from fourteen monitoring wells were analyzed in conjunction with meteorological data using advanced time-series techniques, including Dynamic Time Warping (DTW), to detect temporal shifts in aquifer response. Lag times between rainfall and groundwater rise ranged from 3 to 10 days, depending on local hydrogeological conditions. Piezometric surface maps generated through Inverse Distance Weighting (IDW) interpolation highlighted widespread recharge across alluvial deposits, with groundwater levels increasing from approximately 70 to 72.2 meters above sea level in some areas. These results underscore the value of real-time monitoring networks in capturing aquifer responses to extreme events, contributing to more informed and adaptive water management strategies.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101528"},"PeriodicalIF":4.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265920","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":"Development of a multi-model framework for standardized groundwater index computation: Application to Andhra Pradesh and Telangana states","authors":"Asha Farsana M,&nbsp;Bharath Kumar Reddy Kadapala,&nbsp;Satya Geetha Vimala Channa,&nbsp;Abdul Hakeem K,&nbsp;Chandrasekar K","doi":"10.1016/j.gsd.2025.101523","DOIUrl":"10.1016/j.gsd.2025.101523","url":null,"abstract":"<div><div>Groundwater drought occurs when there is a depletion of groundwater storage and it is marked by unavailability of groundwater supply to meet the irrigation, public, industrial and other demands. Monitoring groundwater levels and groundwater discharge and quantifying them helps predict and mitigate groundwater drought. This study presents an improved and more accurate methodology for the computation of the Standardized Groundwater Index (SGWI) for monitoring groundwater drought. The traditional approaches of calculating standardized indices involve fitting appropriate statistical distributions to the time series data of each observation well. These techniques generally require long-term, well-level data, which may only be available in some cases. This study utilizes monthly groundwater level time-series data from a set of observation wells in Andhra Pradesh and Telangana states, spanning from January 2008 to August 2023, to estimate the Standardized Groundwater Index (SGWI). The study overcomes the limitation of a short data period (16 years) by employing a novel multi-model approach. The Kolmogorov-Smirnov test and Akaike Information Criterion corrected (AICc) were used to identify optimal fit distributions, followed by calculating weighted probabilities of non-exceedance based on model likelihoods. These probabilities were interpolated and transformed into unit normal standard deviates to create the SGWI map for the study area. The SGWI demonstrated a good correlation (R² &gt; 0.74) with other standardized indices, such as the GRACE-Drought Severity Index and the Standardized Runoff Index. The high correlation with long-term runoff-based indices emphasizes the effectiveness of using a multi-model approach in generating standardized indices in data-scarce environments.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101523"},"PeriodicalIF":4.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145319490","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":"Hydrogeochemistry and geothermometry of carbonate aquifers at the southern margin of the northern China coalfield: Insights from major ions and environmental isotopes","authors":"Haitao Zhang ,&nbsp;Guangquan Xu ,&nbsp;Hongbin Zhan ,&nbsp;Xiaoqing Chen ,&nbsp;Xu Li ,&nbsp;Zhuting Wang ,&nbsp;Kai Wang ,&nbsp;Jianghui He ,&nbsp;Zixuan Li ,&nbsp;An'an Zhao ,&nbsp;Hao Wang","doi":"10.1016/j.gsd.2025.101530","DOIUrl":"10.1016/j.gsd.2025.101530","url":null,"abstract":"<div><div>Carbonate aquifers are widely distributed worldwide and are prioritized for the development and utilization of medium-deep geothermal resources. The formation mechanisms of geothermal water in carbonate aquifers, a critical knowledge gap hindering geothermal resource evaluation, were investigated. By analyzing hydrogeochemistry and geothermometry (major ions, δ¹⁸O, δD, δ³⁴S_SO4, δ¹³C_DIC, and A¹⁴C_DIC) from groundwater samples, hydrogeochemical processes, recharge sources, geothermal conditions, and residence times of the geothermal water in Cambrian–Ordovician carbonate aquifers in the Huainan coalfield, located on the southern margin of northern China, were evaluated. The results showed that bounded by the Fufeng and Minglongshan faults, the Huainan coalfield is divided into three structural zones. Cold water in the southern recharge zone (HCO₃-Ca type, 18.1–19.2 °C, TDS 0.28–0.49 g/L) contrasts with geothermal water in the central flow and discharge zone (Cl-Na type, 36.1–50.7 °C, TDS 1.93–3.06 g/L). Geothermal water formation is controlled by evaporite dissolution (halite, gypsum, and anhydrite), common ion effect, dedolomitization, and microbial oxidation of sulfides. Isotopic signatures indicate that geothermal water originates from recharge by Late Pleistocene precipitation (∼34.1 ka) under cold-humid conditions. Silica geothermometers revealed reservoir temperatures of 59.8–80.1 °C (average 67.4 °C) and circulation depths of 1565–2291 m (average 1838 m). A conceptual model of geothermal water circulation in Cambrian–Ordovician carbonate aquifers was established. Driven by topography and gravity, atmospheric precipitation in the southern outcrop zone infiltrated the subsurface, circulated to depth where it reached elevated temperatures, and then ascended through faults and fractures, ultimately discharging via interlayer flow, drilled wells, and natural outlets. Given the slow renewal rate of geothermal water in the study area (average retention time ∼34.1 ka), evaluation of resource renewability prior to extraction is essential to prevent depletion caused by excessive exploitation.</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101530"},"PeriodicalIF":4.9,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145265923","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}