Geochemistry: Exploration, Environment, Analysis最新文献

{"title":"Whole rock lithogeochemical analysis of the Mount Read Volcanics: A new tool for geochemical exploration","authors":"Zebedee Zivkovic, S. Halley, Mike Vicary, Michael Baker, M. Cracknell, Shaun Barker","doi":"10.1144/geochem2024-008","DOIUrl":"https://doi.org/10.1144/geochem2024-008","url":null,"abstract":"The Mount Read Volcanics (MRV) of western Tasmania is a belt of Middle to Late Cambrian submarine volcanics and volcaniclastics and one of the major base and precious metal provinces within Australia. Exploration success in the MRV has been in decline in recent years due to a variety of challenges including intensely altered rocks with complex stratigraphy and lithofacies variation, and a lack of accessible outcrop. As a result, local and regional mapping of the MRV is often restricted to Group-level stratigraphy, rendering geological mapping ineffective for identifying decametre-scale mine stratigraphy.\u0000 Surface rock chip and drill hole samples were collected and analysed using commercially available geochemical assays to create a regional geochemical dataset of the MRV, covering the entire province and all major stratigraphic units. From this data a lithogeochemical methodology was developed, utilizing Ti/Nb and V/Sc systematics that effectively characterizes the samples according to composition and magmatic processes. This method is shown to be robust to biases due to alteration and lithofacies, eliminating the need for highly selective sampling or extensive data filtering.\u0000 To demonstrate the utility of this method in an exploration context, data from the K-lens of the Rosebery polymetallic volcanic-hosted massive sulphide (VHMS) deposit was used as a case study. Using Ti/Nb – V/Sc systematics, a rock composition classification was developed which allowed for discrimination of the footwall, hangingwall and host stratigraphy of the Rosebery Mine Sequence. A geochemical fingerprint for the footwall stratigraphy to mineralisation was developed, and by correlating this signature to the regional unclassified samples, geochemical analogues for the Rosebery Footwall were readily identified. This approach rapidly reduces the exploration search space and provides valuable information for future mineral exploration. The methodology is applicable in other terrains; however, appropriate orientation studies are required to investigate potential biases due to lithofacies, alteration and mineralogical variability.","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"37 23","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141928386","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":"Hydrothermal alteration and elemental mass balance for the Surda Copper Deposit, Singhbhum Shear Zone, Eastern India: Implications for both copper and magnetite-apatite mineralization","authors":"S. Chowdhury, D. Lentz, Dipak C. Pal","doi":"10.1144/geochem2024-004","DOIUrl":"https://doi.org/10.1144/geochem2024-004","url":null,"abstract":"\u0000 This paper explores the geological relationships, mineralogical, and geochemical characteristics, and quantitative elemental mass balance constraints of the hydrothermal alteration zones within the uraniferous Surda copper deposit in the Singhbhum Shear Zone in eastern India, which is affiliated with an iron oxide copper-gold system. Five distinct alteration zones are identified: a proximal potassic (biotitization) zone containing magnetite- apatite; a central chloritization zone containing copper, uranium, gold, and magnetite; distal silicification (quartz) and albitization zones; and a transitional chlorite-sericitization zone. Evidence suggests these zones originated from mafic precursors linked to a subduction zone. Magnetite mineralization shows both magmatic (δ\u0000 18\u0000 O +2.0 to +4.8 ‰) and hydrothermal (δ\u0000 18\u0000 O +0.4 to +0.6 ‰) signatures. Hydrothermal magnetite-apatite formed at temperatures of 440° to 550°C, with continued crystallization at lower temperatures (280° to 360°C) concurrent with copper sulfide and uranium precipitation from an Fe-rich, isotopically heavy fluid (δ\u0000 34\u0000 S + 4.55 to + 9.66‰). Major elements (Ca, Na, Mg) and some minor and rare earth elements decrease from weakly-altered mafic rocks to late alteration zones, reflecting the breakdown of Ca-bearing hornblende, biotite and plagioclase. Potassium decreases from early to late alteration zones due to mineral transformations. Mass-balanced geochemical data align with hydrothermal alteration mineral assemblages, indicating processes like mineral dissolution, element absorption, and sulfide behavior. Overall, the study highlights the complex hydrothermal alteration processes shaping the Surda copper deposit and provides insights into ore formation mechanisms.\u0000","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141828355","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":"Detecting element migration from ore systems: A laser ablation ICP-MS method for the in-situ measurement of element contents and\u0000 207\u0000 Pb/\u0000 206\u0000 Pb values on rough fracture coatings","authors":"Collette Pilsworth, D. Layton-Matthews, M. Leybourne, A. Voinot, Donald Chipley","doi":"10.1144/geochem2024-014","DOIUrl":"https://doi.org/10.1144/geochem2024-014","url":null,"abstract":"\u0000 In-situ elemental content and\u0000 207\u0000 Pb/\u0000 206\u0000 Pb values in three rough fracture coatings within drill cores from the McArthur River unconformity-related uranium deposit, Athabasca Basin, Canada were measured using laser ablation-inductively coupled plasma mass spectrometry (LA-ICP-MS) image mapping. Fracture coating samples were located proximal and distal to the ore deposit. Samples required minimal preparation in this method, with areas (∼500 by 500\u0000 \u0000 \u0000 μ\u0000 \u0000 \u0000 m) targeted in a cell spaced grid pattern using a 50-\u0000 \u0000 \u0000 μ\u0000 \u0000 \u0000 m spot, spaced 200\u0000 \u0000 \u0000 μ\u0000 \u0000 \u0000 m on the x- and y-axis with an offset of 100\u0000 \u0000 \u0000 μ\u0000 \u0000 \u0000 m, to overcome sample surface topography. A five second (s) acquisition time was applied to elemental content measurements and a 2-s acquisition time was applied to\u0000 207\u0000 Pb/\u0000 206\u0000 Pb measurements. These parameters increased the spatial resolution, analytical sensitivity, and minimized the contribution of the host rock underlying the fracture surface to the geochemical signal in comparison to extended acquisition times. In addition, laser ablation temporal profiles allow for the interpretation of the timing of element/isotope migration and fixation on the rough fracture coating.\u0000 \u0000 \u0000 Rasterized maps generated in Iolite\u0000 TM\u0000 v.4 demonstrate the chemical distribution of elements and\u0000 207\u0000 Pb/\u0000 206\u0000 Pb values on the rough fracture coatings, allowing for the identification of mineral phases hosting pathfinder elements, pathfinder element associations, and the generation of bulk in-situ or specific mineralogy geochemical values. Bulk in-situ values calculated using an integration of the 2D image data and targeting the ∼500 by 500\u0000 \u0000 \u0000 μ\u0000 \u0000 \u0000 m surface of the fracture coating compared to previous bulk geochemical methods obtained by sampling the fracture coating with a micro drill (i.e., modified aqua regia (HCl: HNO\u0000 3\u0000 : H\u0000 2\u0000 O), weak acid leach (WAL) (2% HNO\u0000 3\u0000 )), highlights that in-situ analysis greatly improved detection of pathfinder elements on the fracture surface. This study is the first application of in-situ LA-ICP-MS for measuring element contents and\u0000 207\u0000 Pb/\u0000 206\u0000 Pb values on rough fracture coatings and demonstrates its importance as a new geochemical tool to the mining industry for future mineral exploration.\u0000","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141684104","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":"Effectiveness of LOF, iForest, and OCSVM in detecting anomalies in stream sediment geochemical data","authors":"Shahed Shahrestani, Emmanuel John M. Carranza","doi":"10.1144/geochem2024-009","DOIUrl":"https://doi.org/10.1144/geochem2024-009","url":null,"abstract":"This paper compares three unsupervised machine-learning algorithms (local outlier factor (LOF), isolation forest (iForest), and one-class support vector machine (OCSVM)) for anomaly detection in a multivariate geochemical dataset in northeastern Iran. This area contains several Au, Cu, and Pb–Zn mineral occurrences. The methodology incorporates single-element geochemistry, multivariate data analysis, and application of the three unsupervised machine learning algorithms. The PCA unveiled diverse elemental associations with PC1 showing a Co–Cr–Ni–V–Sn association indicating a lithological influence, PC2 shows an Au–Bi–Cu–W association suggesting epithermal gold mineralization, PC3 shows variability in Zn–V–Co–Sb–Cu–Cr, PC4 shows an Au–Cu–Ba–Sr–Ag association indicating gold and polymetallic mineralization, PC5 reflects Zn–Ag–Ni–Pb related to hydrothermal mineralization, and PC6 and PC7 show element associations suggesting epithermal and intrusive-related polymetallic mineralization. It was found that OCSVM performed slightly better than LOF and iForest in detecting anomalies associated with known Cu occurrences and it successfully delineated dispersion from all known Au occurrences. LOF outperformed iForest and OCSVM in identifying all four Pb–Zn occurrences, and the three methods substantially limited the areas of the anomaly class. The analysis showed that LOF produced a less cluttered anomaly map compared to the isolated patterns in the iForest map. LOF was accurate in identifying anomalies associated with Au–Pb mineralization, while iForest detected anomalies associated with Pb–Zn–Cu occurrences and neighboring Pb–Zn occurrence. OCSVM performed similarly in the northern and western areas but displayed unique discrepancies in the southeast and west by detecting anomalies associated with two Cu and a Pb–Cu occurrences. This study examined the influence of contamination fraction on detection of geochemical anomalies, revealing a noteworthy rise in the count of mineral occurrences delineated by anomalies when the contamination fraction increases from 5% to 10%. However, even with a 35% contamination fraction, some Cu occurrences remained outside the anomaly category, indicating potentially overlooked geochemical signals from mineral occurrences due to sampling schemes.","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"8 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141356565","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":"Gold in eskers and gyttja overlying auriferous till, Regnault deposit, Quebec","authors":"Don I. Cummings, Andy Orr, Francis MacDonald","doi":"10.1144/geochem2023-068","DOIUrl":"https://doi.org/10.1144/geochem2023-068","url":null,"abstract":"\u0000 The Regnault gold deposit in Quebec, Canada, was discovered by Kenorland in 2020 following identification of a gold-in-till dispersal train. In 2022, two non-traditional media—eskers and organic lake-bottom mud (gyttja)—were sampled to determine if they likewise contained gold anomalies that vectored the mineral deposit. Striking, coherent (mappable) anomalies exist in both media. The gold-in-esker dispersal train has a similar pathfinder element association as the gold-in-till dispersal train (e.g., Te, W) but contains approximately twice the gold (average 73 ppb Au) in the <63 um fraction. It is hypothesized to be a meltwater-sorted version of the gold-in-till train, sourced from the erosional esker corridor some 3 km upflow. By contrast, the gold-in-gyttja dispersal train is substantially different than both the gold-in-esker and gold-in-till dispersal trains. It has lost significant association with pathfinder elements, contains an order of magnitude less gold (average 4.2 ppb Au), and is\u0000 tentatively\u0000 hypothesized to have a hydromorphic origin, sourced primarily from the gold-in-till dispersal train. The main takeaway from the study is that the sampling of any of these three media—eskers, gyttja or till—could have conceivably led to the discovery.\u0000 \u0000 \u0000 Supplementary material:\u0000 https://doi.org/10.6084/m9.figshare.c.7235784\u0000","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"20 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141100022","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":"Applications of zinc stable isotope analysis in environmental and biological systems: a review","authors":"Tassiane P. Junqueira, B. Vriens, M. Leybourne, Anna L. Harrison, K. Sullivan, H. Jeong, Daniel F. Araújo","doi":"10.1144/geochem2024-003","DOIUrl":"https://doi.org/10.1144/geochem2024-003","url":null,"abstract":"Zinc (Zn) is an essential trace element that is involved in both biotic and abiotic processes in Earth's surface environments. Over the last 20 years, advances in mass spectrometry instrumentation have enabled unprecedented high-precision Zn isotope abundance ratio determinations in natural and anthropogenic samples. Supported by a solid theoretical background inherited from the traditional non-metal stable isotopes (C, N, H, O, S), the understanding of the controlling factors of Zn isotope fractionation has rapidly evolved. In this article, we review the main applications and findings of Zn isotopes in a variety of scientific domains, including metal contamination, magmatic differentiation, plant uptake, weathering, global climate change, dietary and trophic chains, and biomedicine. The analytical aspects of Zn isotope determination in solid and water samples and the principles and mechanisms of Zn isotope fractionation are also reviewed. This work aims to provide a general yet in-depth panorama of Zn isotope chemistry and demonstrate the versatility and potential of this isotope system for studying the biological, geological, and chemical cycling of Zn.\u0000 \u0000 Supplementary material:\u0000 https://doi.org/10.6084/m9.figshare.c.7240146\u0000","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"35 40","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141117464","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":"Factor analysis in residual soils of the Iberian Pyrite Belt (Spain): Comparison between raw data, log transformation data and compositional data","authors":"I. Martín-Méndez, Juan F. Llamas-Borrajo, Alberto Llamas Lois, J. Locutura","doi":"10.1144/geochem2024-005","DOIUrl":"https://doi.org/10.1144/geochem2024-005","url":null,"abstract":"The Iberian Pyrite Belt (IPB) is a metallogenic province in SW Spain and Portugal hosting the largest concentration of massive sulphide deposits worldwide. Exploration campaigns in both the Spanish and Portuguese sectors of the IPB have increased recently due to the rise in metal prices.\u0000 Within this framework, distinguishing geochemical features associated with natural phenomena and isolating geogenic anomalies from anthropogenic ones can pose a challenge. This contribution uses the residual soil geochemical database of the IPB (Spain) to examine numerous variables, encompassing major, minor, and trace elements. Some of these variables commonly exhibit high correlations owing to consistent geochemical behavior. However, the influence of anthropogenic factors tends to elevate data variability, occasionally masking the natural relationships that govern their distributions.\u0000 We apply different treatments of data to develop factor analysis using log transformed data, and clr-transformed data to compare and improve the geochemical interpretation of this important zone. Factor analysis has been developed with these results to compare with previously published research on factor analysis in raw data. Factor score interpolated maps were also generated using both lognormal and clr-transformed data to visualize better the distribution and the different geochemical associations in the Iberian Pyrite Belt.\u0000 This study shows the importance of the different data treatments and the improvement of the clr-transformed multivariate analysis to reduce the dilution or overestimation of the results of some elements that cause erroneous interpretations of the data.","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"12 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141042081","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":"Assessing soil contamination by potentially toxic elements in artisanal and small-scale gold mining sites of the Adamawa Region, Cameroon","authors":"S. Danala Danga, L. Ekengele Nga, T. Makhubela, B. Ibrahim, D. L. Bitom, J. D. Kramers","doi":"10.1144/geochem2023-055","DOIUrl":"https://doi.org/10.1144/geochem2023-055","url":null,"abstract":"Gold mining is acknowledged as a principal source of environmental contamination, primarily due to the release of potentially toxic elements (PTEs) through tailings dispersion into adjacent soils. Such contamination leads to land degradation, pollution, biodiversity loss, and soil contamination, and subsequently impacts the food chain, human health, and soil ecosystems. This study evaluates the extent of PTE contamination in soils at artisanal and small-scale gold mining (ASGM) sites within the Meiganga area of the Adamawa-Yade Domain, Cameroon. ASGM extraction processes from quartz veins in this area involve the removal of topsoil to access the ore. Comparative analysis of soil samples from three profiles within the mining zone were conducted to determine contamination levels using pollution indices: enrichment factor, geoaccumulation index, contamination factor and pollution load index. Results indicate higher concentrations of PTEs in soils from the mining area compared to the control profile, with notable contamination in the bottom slope profiles and B horizons, reflecting considerable metal accumulation. The contamination levels of PTEs substantially exceed background levels in the upper continental crust. The study attributes the elevated concentrations of PTEs not only to local mineralization but also to anthropic activities, particularly ASGM, which contributes to their enrichment, distribution, and mobility. This pronounced contamination necessitates immediate intervention, advocating for pollution control measures to address potential ecosystem and human health risks. It highlights the environmental toll of ASGM and underscores the imperative for sustainable mining practices and effective soil remediation techniques, including phytoremediation and soil replacement, to alleviate the adverse effects.\u0000 \u0000 Supplementary material:\u0000 https://doi.org/10.6084/m9.figshare.c.7195773\u0000","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140658611","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":"Mapping exploration targets through multifractal modelling of soil geochemical data in the Xiaohongshilazi Pb-Zn-(Ag) ore district, Jilin Province, NE China","authors":"Huchao Ma, Da Wang, Feng Bai, Xiaoxuan Zhang, Gaotian Wang, Saina Dong, Guilong Wang","doi":"10.1144/geochem2023-067","DOIUrl":"https://doi.org/10.1144/geochem2023-067","url":null,"abstract":"The Xiaohongshilazi Pb-Zn-(Ag) ore district, located in the Jizhong–Yanbian Metallogenic Belt in NE China, presents challenges in identifying geochemical anomalies and prospecting minerals due to thick covers, complex geological evolution, and mining activities. To overcome these obstacles, we adopted an innovative approach that combines multifractal theory with concentration-area (C-A) modelling and local singularity analysis (LSA) to characterize the geochemical signature. Initially, factor analysis of log-transformed data was used to identify ore-forming factors, which were then modelled using C-A and LSA. Subsequently, modelling results were compared to conventional maps generated using inverse distance weighted (IDW) interpolation. Additionally, the C-A model was employed to establish thresholds for singularity indices generated by LSA for target mapping. The results revealed a close relationship between Factor 1 (F1) and mineralization. The C-A model of F1 failed to detect weak anomalies compared to the IDW-interpolated map, while LSA not only identified weak anomalies but also enhanced the detection of reliable anomalies. Three prospecting targets (PT-01, PT-02, and PT-03) were identified. Validation of PT-01 using new drillholes and existing mineralization confirms the effectiveness of targets and the accuracy of the model. Our approach provides a robust alternative for prospecting ore districts encountering similar challenges.","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":"47 2","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140675960","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":"Graph convolutional network for lithological classification and mapping using stream sediment geochemical data and geophysical data","authors":"Hao Fang, Yue Liu, Qingteng Zhang","doi":"10.1144/geochem2024-006","DOIUrl":"https://doi.org/10.1144/geochem2024-006","url":null,"abstract":"Lithological mapping plays a vital role in acquiring a comprehensive understanding of subsurface rocks and geological structures. Traditional lithological mapping relies heavily on manual field surveys, with the accuracy of the mapping greatly constrained by the expertise of mappers, and thus this process is commonly slow and costly. In the present study, the graph convolutional network (GCN) method was proposed for efficient and automatic lithological mapping, using various geological survey data (e.g., geochemical and geophysical data). The GCN is not limited by the spatial distribution of sampling data, and hence it can be directly applied to the integrated resampling data that do not adhere to the regular spatial distribution patterns of Euclidean space. To evaluate the potential application of the GCN method in lithological classification and mapping, a case study was conducted in the Maqin region (China). Geochemical and geophysical data were utilized as the basis for lithological classification, as they can provide valuable information on geochemical compositions and physical properties of geological bodies, respectively. The study process was primarily divided into three parts. First, basic pre-processing was conducted on the geochemical data and the geophysical data, including centered log-ratio (clr) transformation and resampling. Subsequently, the resampled points were divided into training and testing sets in the proportion of 5.5:1. In the training set, 20% of the points are randomly selected as the validation set. Ultimately, using each resampled point as a node and the integrated geochemical and geophysical data as features, a GCN model and an undirected graph were constructed based on an adjacency distance of one kilometer. The graph was employed by the constructed GCN model for lithological classification. The results reveal that the majority of lithological units can be accurately classified with an overall accuracy of 86%, indicating that the GCN model exhibits good applicability in lithological classification.","PeriodicalId":518453,"journal":{"name":"Geochemistry: Exploration, Environment, Analysis","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140689643","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}