Journal of Geochemical Exploration最新文献

{"title":"Age and genesis of the largest Phanerozoic Mn deposits in the Paratethys: Inferences from 40Ar/39Ar and U/Pb ages in NE Bulgaria and NW Turkey","authors":"Peter Marchev ,&nbsp;Raya Raicheva ,&nbsp;Rositsa Ivanova ,&nbsp;Brian Jicha ,&nbsp;Irena Peytcheva","doi":"10.1016/j.gexplo.2025.107764","DOIUrl":"10.1016/j.gexplo.2025.107764","url":null,"abstract":"<div><div>The early Oligocene manganese (Mn) deposits around the Black Sea represent the second largest accumulation of Mn in the world (600 × 10⁶ tons). Various hypotheses have been offered to explain the genesis of these deposits. However, very few can explain all the major characteristics of the Mn deposits, in particular: 1) their contemporaneity and short depositional time; 2) vast covered territory; 3) the source of the great volume of metals (Mn, Fe, P and Si) and 4) the mechanisms of metal precipitation and concentration. Most of the former hypotheses assume the source for the Mn is the local crystalline rocks, ignoring or misinterpreting the involvement of volcanic material. Here, we propose a volcanic-derived model sourced from a 33.2 ± 0.1 Ma supereruption from the Rhodope Massif, Bulgaria, which covers large areas of the Central, Southern and Eastern Europe with ash. The model is based on radioisotopic age data of the volcanic material from two of the Mn deposits, located on the western shore of the Black Sea. Our model implies that the Mn (along with other metals, Fe, P, Si) have been transported by the large amount of erupted dust and aerosols with absorbed soluble fluoride, chloride, and sulfate metals. The fast dissolution of gases and aerosols into restricted or shallow Paratethys sea basins produced anoxic-euxinic conditions, which in turn promoted high concentration and deposition of the Mn. Final structuring of the zonation of the deposits was the result of the restoration of the normal sea redox-stratification after the end of the volcanic influence.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107764"},"PeriodicalIF":3.4,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geostatistical modelling of mine tailings and comparative analysis of sampling methodologies: A case study of the Otanmäki ilmenite tailings storage facility project","authors":"Tuomas Leskelä ,&nbsp;Janne Hokka ,&nbsp;Teemu Karlsson","doi":"10.1016/j.gexplo.2025.107759","DOIUrl":"10.1016/j.gexplo.2025.107759","url":null,"abstract":"<div><div>Increasing concerns about the availability of Critical Raw Materials (CRMs) have shifted focus to extractive waste sites as potential sources for secondary resources. Resource assessment requires robust investigation and resource definition, necessitating representative sampling and use of an appropriate modelling method. In this study, spatial sampling sensitivity was tested at the Otanmäki tailings storage facility (TSF) by conducting multiple models at different scales, utilizing both previously collected and new data. Additionally, three tailings sampling methodologies were evaluated to ensure sample representativity and minimize contamination: a tube sampler with a valve, a flow-through blade, and an auger drill.</div><div>Results indicated that both the auger drill and the tube sampler perform well and provide similar results under low moisture conditions. However, the tube sampler was estimated to be more accurate in varying conditions, despite it having a smaller sample volume and being more time-consuming to use. According to the modelling results, there were minimal changes in grade and tonnage when increasing sampling density or changes in model scale. Thus, the existing resource estimation from the Otanmäki TSF that was based on a 100 × 100 m grid could be considered as having a high-confidence in relation to the G-category in the United Nations Framework Classification for Resources (UNFC) system with effective investigation of tailings sites requires a tailored approach considering factors such as ore deposit type, mineralization style, and information on ore processing and tailings disposal practices. This work provides insights into tailings resource modelling, estimation confidence, sample representativity, and optimal sampling strategies, aiding in the resource classification of tailings sites.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107759"},"PeriodicalIF":3.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of uranium exposure in drinking water sources across Ganderbal, Jammu and Kashmir: A biokinetic modelling approach","authors":"Mehak Mohi u Din ,&nbsp;Salik Nazir ,&nbsp;Shakeel Simnani ,&nbsp;Mohammad Rafiq Chakan ,&nbsp;Sajad Masood ,&nbsp;Supriya Rani ,&nbsp;Amit Kumar Singla","doi":"10.1016/j.gexplo.2025.107763","DOIUrl":"10.1016/j.gexplo.2025.107763","url":null,"abstract":"<div><div>In response to concerns regarding potential health risks like nephritis, potential alterations to bone structure, and carcinogenic effects associated with uranium contamination in drinking water, a comprehensive study was conducted across Ganderbal, Jammu &amp; Kashmir to address concerns about potential health hazards associated with uranium contamination in drinking water. The study quantified uranium concentrations in 153 water samples collected from various sources. The uranium concentrations ranged from 0.51 to 6.83 μg L⁻¹, with an average concentration of 1.15 μg L⁻¹. The age and gender-specific annual effective ingestion doses were calculated along with carcinogenic and non-carcinogenic health risks. The study used Li's hair compartment model to analyze the biokinetics and toxic effects of uranium within the adult human body, particularly focusing on distribution, target organs for retention, and uranium excretion over a 60-year exposure period.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107763"},"PeriodicalIF":3.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143704617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Health risks due to geogenic and anthropogenic influences on groundwater quality in Southern India's hard rock terrain","authors":"B. Preethi ,&nbsp;T. Subramani ,&nbsp;R. Saravanan ,&nbsp;P. Gopinathan ,&nbsp;Zaixing Huang ,&nbsp;Brajesh Kumar","doi":"10.1016/j.gexplo.2025.107762","DOIUrl":"10.1016/j.gexplo.2025.107762","url":null,"abstract":"<div><div>Groundwater contamination poses a critical public health risk in Raichur district, Karnataka, India where groundwater is a vital resource for drinking and agriculture. A total of 54 groundwater samples were analyzed, revealing that 68.5 % exceeded the WHO's nitrate limit of 45 mg/L, with concentrations ranging from 2.2 mg/L to 830 mg/L, and 44.4 % surpassed the fluoride threshold of 1.5 mg/L, with levels ranging from 0.06 mg/L to 7.18 mg/L. A comprehensive Health Risk Assessment (HRA) identified infants, children, pregnant women, and lactating mothers as vulnerable populations, with Hazard Quotient (HQ) values reaching 67.25 for nitrate and 23.33 for fluoride. These elevated levels indicate significant risks, including methemoglobinemia and skeletal fluorosis. Geospatial analysis mapped contamination hotspots in the northern and central regions, highlighting the interplay of anthropogenic activities like excessive fertilizer use, inadequate waste management, and natural geological factors. Recommendations include precision farming, improved waste management, and community-level remediation systems, such as defluoridation and denitrification technologies. Artificial groundwater recharge and regulatory interventions are critical to maintaining water quality. By integrating geospatial tools and HRA, this study provides a replicable framework for addressing groundwater contamination and ensuring sustainable water resource management, particularly in regions with similar hydrogeological challenges.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107762"},"PeriodicalIF":3.4,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143724927","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gallium isotope variation in the Anning carbonate-hosted clay-type lithium deposit, Central Yunnan Province, China: Implications for the Li enrichment mechanism","authors":"Yuxu Zhang ,&nbsp;Hanjie Wen ,&nbsp;Pan Qiao ,&nbsp;Chuanwei Zhu ,&nbsp;Haifeng Fan ,&nbsp;Shengjiang Du","doi":"10.1016/j.gexplo.2025.107761","DOIUrl":"10.1016/j.gexplo.2025.107761","url":null,"abstract":"<div><div>Lithium deposits are mainly divided into three types: pegmatite-type, brine-type, and clay-type. Compared with traditional pegmatite-type and brine-type lithium deposits, clay-type lithium deposits have attracted increasing attention due to their large scale and stable distribution. We investigated the Ga isotope composition of three drill cores (ZK401, ZK406, and ZK408) in the Anning carbonate-hosted clay-type lithium deposit in central Yunnan Province, China. The δ⁷¹Ga_NIST994 values and Ga contents of the claystone sample from drill core ZK401 are 0.97–1.33 ‰ and 1840–4070 ppm, respectively, with a negative correlation between the Ga content and δ⁷¹Ga_NIST994 value. For drill core ZK406, the δ⁷¹Ga_NIST994 values and Ga contents of the claystone sample are 1.26–1.48 ‰ and 29.8–5950 ppm, respectively, with a positive correlation between the Ga content and δ⁷¹Ga_NIST994 values. For drill core ZK408, the δ⁷¹Ga_NIST994 values and Ga contents of the claystone sample are 1.04–1.22 ‰ and 2.70–4990 ppm, respectively, with no significant correlation observed. Previous studies have suggested that smectite is the precursor of Li-bearing minerals. However, the X-ray diffraction analysis showed that the clay minerals in the three drill cores were primarily illite, clinochlore, kaolinite, and diaspore/boehmite, indicating that these clay minerals underwent mutual transformation during the diagenesis process. The Ga isotope data suggested that during the mineral conversion process, solid-state transformation was the dominant reaction mechanism of the strata in drill core ZK401, while dissolution-crystallization was the dominant reaction mechanism of the strata in drill core ZK406. The cancellation of both mechanisms' effects may explain the lack of a clear correlation between the Ga contents and δ⁷¹Ga_NIST994 values in drill core ZK408. Lithium is more likely to be preserved via the solid-state transformation mechanism during the conversion of the parent mineral (such as smectite) into daughter minerals (such as illite and clinochlore), while the dissolution-crystallization mechanism is more likely to lead to the redistribution of Li.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107761"},"PeriodicalIF":3.4,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143703917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magmatic fertility of porphyry Ag-Pb-Zn deposits revealed by zircon and apatite chemistry: An example of the Lengshuikeng Ag-Pb-Zn deposit in South China","authors":"Xinlu Hu ,&nbsp;Yongpeng Ouyang ,&nbsp;Runling Zeng ,&nbsp;Jinwei Li ,&nbsp;Libo Li ,&nbsp;Yi Shang","doi":"10.1016/j.gexplo.2025.107757","DOIUrl":"10.1016/j.gexplo.2025.107757","url":null,"abstract":"<div><div>Porphyry Ag-Pb-Zn deposits are globally rare, with limited understanding of their magma origins, compositions, and physical-chemical conditions. To address this, we conducted a comprehensive investigation of the chemical and Sr<img>Nd isotopic composition of apatites, along with the U<img>Pb dating, trace element analysis, and Lu<img>Hf isotopic analysis of zircons from the igneous rocks at the giant Lengshuikeng Ag-Pb-Zn deposit in South China. The igneous rocks at Lengshuikeng are primarily composed of granite porphyry, K-feldspar granite porphyry, and volcanic rocks of the Daguding and Ehuling Formations. LA-ICP-MS zircon U<img>Pb dating yielded ages 159.7 ± 2.0 Ma for the rhyolitic tuff of the Ehuling Formation, 159.0 ± 2.3 Ma for the granite porphyry, and 152.5 ± 1.9 Ma for the K-feldspar granite porphyry. Combined with previously published age data, we propose that the Ehuling Formation experienced at least two eruption stages: the first at ca. 160 Ma (S1), and the second at 147–138 Ma (S2). The K-feldspar granite porphyry intruded in two stages, dated at 152.5 Ma (S1) and 138–136.6 Ma (S2). The evolutionary sequence of igneous rocks is inferred as: Daguding Formation → Ehuling Formation (S1) → granite porphyry → K-feldspar granite porphyry (S1) → Ehuling Formation (S2) → K-feldspar granite porphyry (S2).</div><div>Zircons from these rocks show ε_Hf(t) values of −13 to −8.5. The (⁸⁷Sr/⁸⁶Sr)_i ratios and ε_Nd(t) values of apatite vary from 0.7075 to 0.7171 and from −12.7 to −4.5, respectively. Similar Sr-Nd-Hf isotopic compositions indicate a common source for these igneous rocks, all derived from partial melting of Paleo- to Mesoproterozoic continental crust. Comparable zircon Ce⁴⁺/Ce³⁺ and Ce/Ce^⁎ ratios and apatite Mn-Ce-Eu-Ga contents indicate similar oxidation states and water contents in the parental magmas. Compared to regional porphyry Cu deposits, the parental magma of the Lengshuikeng Ag-Pb-Zn deposit has lower oxygen fugacity and S concentration. Apatites from the ore-forming granite porphyry have significantly higher concentrations of Cu, Zn and Cl than those from other igneous rocks. Our study suggests that the metal and Cl⁻ contents within parental magma, rather than the oxidation state and water content, are key factors controlling porphyry Ag-Pb-Zn mineralization. Apatite Cu, Zn and Cl contents can serve as valuable indicators of magma fertility in porphyry Ag-Pb-Zn deposits.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107757"},"PeriodicalIF":3.4,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemistry and U-Pb dating of the Yahyalı pluton and associated skarn occurrences, SW Kayseri (Central Türkiye): Geodynamic significance and relation to mineralization","authors":"Fatma Şişman Tükel ,&nbsp;Deniz Tiringa ,&nbsp;Nurullah Hanilçi ,&nbsp;Bülent Ateşçi ,&nbsp;Namık Aysal ,&nbsp;İsmet Alan","doi":"10.1016/j.gexplo.2025.107756","DOIUrl":"10.1016/j.gexplo.2025.107756","url":null,"abstract":"<div><div>The Yahyalı Pluton is an intrusion that intruded into the Yahyalı Nappe in the Eastern Taurus Belt. However, its outcrops are observed in a narrow area due to insufficient erosion depth and few studies have been carried out. This pluton is mainly composed of granite, granodiorite, diorite and monzonite. These facies are predominantly calc-alkaline and partly high-K calc-alkaline series, with an I-type character. The geochemical behaviour of the pluton suggests that mafic magmas of mantle origin have undergone a high degree of fractional crystallization (FC) and may have been partially mixed and/or contaminated by felsic magmas of crustal origin.</div><div>In this study, the Yahyalı pluton and associated garnet skarn formations were dated for the first time. Zircon U-Pb dating of samples taken from different levels of the Yahyalı pluton yielded concordia ages of 52.37 ± 0.41 Ma, 53.66 ± 0.30 Ma, 52.59 ± 0.37 Ma and 52.05 ± 0.36 Ma, respectively. In addition, a lower intercept age of 50.1 ± 3.3 Ma (MSWD = 1.4) (Early Eocene) was obtained from garnet skarn formations. Although the pluton has limited outcrops, associated mineralization (Fe and Fe-Cu skarn, Pb-Zn) occurs over an extensive area, suggesting that large parts of the pluton may not have been eroded. This suggests that the Yahyalı pluton is a fertile magma in terms of mineralization and that there is a high potential for skarn, hydrothermal and porphyry-type mineralization associated with the magmatic system at deeper depths in the region.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107756"},"PeriodicalIF":3.4,"publicationDate":"2025-03-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143703918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A semi-supervised learning framework for intelligent mineral prospectivity mapping: Incorporation of the CatBoost and Gaussian mixture model algorithms","authors":"Mahsa Hajihosseinlou ,&nbsp;Abbas Maghsoudi ,&nbsp;Reza Ghezelbash","doi":"10.1016/j.gexplo.2025.107755","DOIUrl":"10.1016/j.gexplo.2025.107755","url":null,"abstract":"<div><div>Semi-supervised learning warrants more significant consideration for machine learning-based mapping in mineral exploration, since mineral deposits frequently exhibit imbalances in occurrence frequencies. It can potentially address challenges associated with class imbalances via the efficient use of labeled data and the extrapolation of patterns from unlabeled data. This research endeavors to present a prospective model for Mississippi Valley-Type lead and zinc deposits employing a semi-supervised approach in the Varcheh district, western Iran. To achieve this goal, diverse exploratory criteria related to mineralization, encompassing geological, remote sensing, geochemical, and structural layers, have been incorporated to develop a semi-supervised mineral prospectivity model. The model strengthens the advantages of supervised and unsupervised learning approaches by incorporating the Categorical gradient Boosting (CatBoost) and Gaussian mixture model algorithms into a semi-supervised framework. This approach effectively utilizes limited labeled data, while capturing spatial patterns and relationships in the unlabeled dataset, ultimately contributing to a more robust mineral prospectivity mapping model. Indeed, the regions with high posterior probability include most lead and zinc deposits in this strategy, suggesting that the locations of known deposits are significantly tied to areas connected to high posterior probability. The semi-supervised proposed framework in this paper is also compared with supervised approach to validate the performance improvement. The implemented approach can be highly valuable for exploring resources.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107755"},"PeriodicalIF":3.4,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143680097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between distribution of iodine in soil and iodine deficiency disorders (IDD) in China","authors":"Qingqing Liu ,&nbsp;Xueqiu Wang ,&nbsp;Daxing Zhai ,&nbsp;Bimin Zhang ,&nbsp;Lanshi Nie ,&nbsp;Qinghua Chi ,&nbsp;Jian Zhou ,&nbsp;Wei Wang ,&nbsp;Hanliang Liu ,&nbsp;Dongsheng Liu ,&nbsp;Yining Zhou ,&nbsp;Chan Chang","doi":"10.1016/j.gexplo.2025.107758","DOIUrl":"10.1016/j.gexplo.2025.107758","url":null,"abstract":"<div><div>Iodine deficiency disorder (IDD) is a serious public health issue in China. As iodine in the environment is the fundamental cause of iodine-endemic diseases, investigating the distribution and controlling factors of iodine in the soil of endemic disease areas for the accurate prevention and control of endemic diseases is important. This paper aimed to examine the concentration and spatial distribution of iodine in soil of China, along with its correlation with IDD, and explore the influence of geological background, soil types, and geomorphoclimatic landscapes. Based on the data of China Geochemical Baseline (CGB) project, China can be divided into seven high- and three low-value zones. We found that the formation of low-value zones is associated with the high mobility of iodine. According to the Specification of Land Quality Geochemical Assessment, I-deficient soil accounts for nearly 70 % of the land area in China. Meanwhile, the distribution of severe endemic diseases was more consistent with that of iodine concentration (&lt;0.654 mg/kg) in top samples. The high-value zones were closely related to biological affinity and adsorption of iodine, and were mainly distributed in areas with high organic carbon content and coastal areas. The distribution characteristics of iodine in soil and that of IDD were also linked to the geological background, soil types, and geomorphoclimatic landscapes. The predominant soil type in seriously endemic diseases areas was Argosols, and the predominant geomorphoclimatic landscapes was alpine canyons, accumulated Gobi desert, and karst regions. Apart from the karst terrain, other soil types and geomorphoclimatic landscapes mentioned above exhibited low-iodine concentrations.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"275 ","pages":"Article 107758"},"PeriodicalIF":3.4,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143859579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Driving factors of soil selenium accumulation in regional enrichment area at selenium-deficient soil belt of China: An enlightenment of Moran's index and machine learning","authors":"Yuanli Qin ,&nbsp;Li Zhang ,&nbsp;Qiaolin Wang ,&nbsp;Yuntao Song ,&nbsp;Min Peng ,&nbsp;Hangxin Cheng","doi":"10.1016/j.gexplo.2025.107746","DOIUrl":"10.1016/j.gexplo.2025.107746","url":null,"abstract":"<div><div>Selenium (Se) is one of the most indispensable trace elements for human beings, known as the ‘longevity element’ in the 21st century. Due to the complexity of the global geological environment, the distribution of soil Se varies significantly across the world. Understanding the distribution pattern and driving factors of soil Se enrichment is crucial for land resource development and addressing “hidden hunger”, especially in regions where soil Se is abundant. Therefore, a soil geochemical survey was conducted in the Baoshan area of southwest China, which is located at the Se-deficient soil belt yet exhibited characteristics of soil Se enrichment. Combined with Moran's I analysis and machine learning (ML), the enrichment and distribution characteristics, and driving factors of soil Se in this region were revealed. Specifically, we quantify the feature importance of each key factors. Additionally, distribution of soil Se demonstrated strong spatial dependence. The results from Bivariate Moran's I analysis, back-propagation artificial neural networks (BP–ANN) and random forest (RF) models indicated that soil organic carbon (SOC), pH, manganese (Mn), weathering eluvial index (ba), land use and parent materials are the primary driving factors of soil Se retention at the regional scale in Baoshan. In contrast, climate and topography, which are common factors affecting Se distribution at global and continental scales, were found to have no effect on Se retention at this regional scale. Based on the RF model, the relative importance of key driving factors are SOC (24.5 %), land use (21.1 %), pH (15.5 %), ba (15.2 %), parent materials (12.0 %), and Mn (11.9 %). These findings provide valuable guidance for agricultural managements planning and for adjusting agricultural planting structures in marginal and soil Se-rich regions of the traditional Se-deficient soil belt in China.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"274 ","pages":"Article 107746"},"PeriodicalIF":3.4,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}