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<jats:p> Extensive research has been conducted to evaluate mineral resource potential based on geochemical data, but this work is still challenging due to the existence of multiple evaluation solutions based on different methods. In this paper, we combine the multifractal analysis method with typical multivariate statistical methods to analyse the spatial characteristics of geochemical stream sediment data, aiming to quantitatively study the ore-forming potential of the elements in the Central Kunlun area of Xinjiang, China. An <jats:italic>R</jats:italic> -type cluster analysis, Pearson correlation analysis, and principal component analysis are used to explore the correlations among the 12 target elements. The multifractal model is constructed using the method of moments to analyse the spatial distribution patterns of the elements, and corresponding multifractal parameters are extracted to quantitatively describe their ore-forming strengths in the study area. The results show that Co, V, Ti, Fe <jats:sub>2</jats:sub> O <jats:sub>3</jats:sub> , MgO and Cu compose a group of elements closely related to the regional geological background, while Pb, Zn, Bi, Sn, Au and Ba are potential metallogenic elements with relatively high ore-forming strengths and favourable ore-forming potential. Multifractal theory further validates and evaluates the favourable ore-forming element group obtained through conventional geochemical multivariate statistical methods, thus providing a new idea for small-scale geochemical prospecting. </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Applications of Innovations in Geochemical Data Analysis collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/cc/applications-of-innovations-in-geochemical-data-analysis">https://www.lyellcollection.org/cc/applications-of-innovations-in-geochemical-data-analysis</jats:ext-link> </jats:p>

<jats:p> The Patterson Lake Corridor (PLC) along the southwestern margin of the Athabasca Basin contains high-grade uranium deposits entirely within crystalline basement rocks. Visible–near infrared–shortwave infrared (VNIR–SWIR) spectroscopy measurements were collected on drill core samples from several locations in the PLC. The Triple R and Arrow deposits exhibit downhole spectral trends related to the crystallinity and thermal maturity of clays (illite and kaolinite) and mineralization. The K–Ar dates of silt-and-clay size fractions (10–6  <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> </mml:math> </jats:inline-formula> m; 6–2  <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> </mml:math> </jats:inline-formula> m; 2–0.6  <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> </mml:math> </jats:inline-formula> m; 0.6–0.2  <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> </mml:math> </jats:inline-formula> m; &lt;0.2  <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>μ</mml:mi> </mml:math> </jats:inline-formula> m) from five clay-altered samples decrease with grain size, and span 1608 ± 17 Ma to 1060 ± 14 Ma for the Spitfire discovery ( <jats:italic>n</jats:italic>  = 14) and 1342 ± 17 Ma to 289 ± 4.3 Ma for the Arrow deposit ( <jats:italic>n</jats:italic>  = 4). Alteration assemblages are broadly similar to Athabasca Basin basement-hosted deposits, and K–Ar dates indicate that high-grade uranium mineralization in the PLC reflects remobilization and concentration of primary ores. Integration of geochronology, clay mineralogy and VNIR–SWIR spectral parameters identify fertile fluid conduits when expanded to property or corridor scales, and provide additional evidence that ore grades of the Athabasca Basin deposits reflect several stages of hydrothermal mineralization spanning <jats:italic>c.</jats:italic> 1000 Ma. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Supporting information document and datasets are available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6033890">https://doi.org/10.6084/m9.figshare.c.6033890</jats:ext-link> </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Uranium Fluid Pathways collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/cc/uranium-fluid-pathways">https://www.lyellcollection.org/cc/uranium-fluid-pathways</jats:ext-link> </jats:p>

<jats:p>The influence of alkalinity and other factors on the content of microelements in soils developed on marine deposits is studied. Traditional indicators of exchangeable sodium percentage do not demonstrate the ability to retain microelements, but one can see a close direct correlation between the content of macroelements and the retention of microelements. The efficiency of this group is increased if we take into account the concentration of total Na. The element compositions of soil were determined by neutron activation method. The results show that the Na-related alkalinity of soil can enhance the role of the main macroelements and increase the dispersibility of particles and their aggregating capacity relative to the microelements. The microelement composition was also determined in Gleyic Solonchaks using the Zn concentration due to the anionogenic composition of gley.</jats:p>

<jats:p> Three new world-class sediment-hosted stratiform copper deposits have recently been documented in SW Poland, in the deep parts of the Fore-Sudetic Monocline: Nowa Sól, Sulmierzyce North and Mozów. Along with the adjacent prognostic areas, these deposits form an extensive W-E trending belt, distant from the well-known deposits of the Sieroszowice-Lubin area and referred to as the Northern Copper Belt. This major discovery was a result of an exploration program performed by the Canadian Miedzi Copper Corporation, which involved studies of archival data and the company's own drilling program. Investigation of the core material included microscopic observations of thin sections and chemical analyzes using the ICP-MS and/or ICP-OES method. The aim of this study was to compare available geochemical data from the documented deposits and determine the distribution patterns of the main and accompanying metals. Particular attention was paid to Cu, Ag, Pb, Zn, Co, Ni, Mo, V and Au. Each of the studied deposits is characterized by a different position of the ore mineralization in the lithological profile. Average concentrations of analyzed elements and their distribution in the ore series, both vertically and laterally, indicate that distinct mineralizing systems were responsible for the formation of each orebody. Among the main factors influencing metal distribution in analyzed deposits are: the spatial range of the epigenetic, oxidized <jats:italic>Rote Fäule</jats:italic> facies; composition and thickness of the source rocks for the mineralizing brines; tectonics. </jats:p>

<jats:p> Few studies have focused on the application of the Tl isotopic system for geochemical exploration. We report <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values of rock samples from the TL Deposit, British Columbia, Canada – a sediment-hosted massive sulfide (SHMS) deposit with characteristics of a Broken Hill-type deposit – and investigate relationships with major and trace element geochemistry. Maps generated using Tl isotope and trace element data indicate that <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values can potentially be used to fingerprint ore mineralization at the TL Deposit. The sources of Tl and other metals (Ag, Pb, Zn) are assessed using Tl isotope data. Measured <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values exhibit positive correlations with Pb, sedimentary exhalative metal index (Zn + 100*Pb + 100*Tl), and the redox proxy, U/Th, and negative correlations with Be, Cd, Ce, La, Ni and Th. Individual lithologies have distinct Tl isotopic compositions. Metal-rich heavily altered samples have relatively high <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values (−5.0 to −2.5 <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> -units) reflecting the euxinic conditions of the global Paleoproterozoic ocean and hydrothermal influence. Samples with lower <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values (−15 to −7.6 <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> -units) reflect a combination of their mineralogy (phyllosilicate minerals such as biotite and clinochlore), Tl from sediments reflecting the Tl isotopic composition of modern seawater, and possible low-temperature alteration processes. Samples with high Pb and Ag contents have high <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values, indicating a hydrothermal origin of these metals, whereas Zn is highest in samples with low <jats:inline-formula> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mi>ε</mml:mi> </mml:math> </jats:inline-formula> <jats:sup>205</jats:sup> Tl values, indicating a low-temperature or sedimentary origin. Thallium isotopes, paired with conventional geochemical data, show promise as a useful tool for exploration of SHMS deposits with Broken Hill-type characteristics. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> Major, minor and trace element contents of samples and reference materials, blank values, correlation coefficient values, and XRD patterns are available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6370671">https://doi.org/10.6084/m9.figshare.c.6370671</jats:ext-link> </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Geochemical processes related to mined, milled, or natural metal deposits collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits">https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits</jats:ext-link> </jats:p>

<jats:p> Laboratory based laser-induced breakdown spectroscopy (LIBS) instruments have proven themselves for trace element analysis of an extensive range of elements. As portable devices have evolved greatly in recent years, new areas of field-application are opening up. However, no portable LIBS (pLIBS) has yet been used for quantitative inorganic water analysis. The aim of this study was to explore whether pLIBS combined with a surface enhanced (SE) liquid to solid conversion (LSC) method can quantify light alkali element concentrations in standard solutions. Multivariate calibrations were performed with single element standard solutions at detection limits of 0.006, 0.011, and 0.007 mg/L for Li, Na, and K, respectively. Coefficients of determination (R <jats:sup>2</jats:sup> ) for the calibration lines from 0.1 to 100 mg/l for Li and Na, and 0.1 to160 mg/L for K were between 0.96 and 0.99. It has been shown that the surface preparation technique used improves the homogeneity of the spread and shape of the evaporation residue and thus accuracy and precision of the analysis. Hence, this study demonstrates that it is possible to quantify light alkali metals in single element standard solutions in the range of 0.1 to 160 mg/L handheld LIBS. </jats:p>

<jats:p> Shizhuyuan is a world-class W-Sn supergiant polymetallic deposit, with a large area of potential mineralization around it. <jats:italic>Dicranopteris dichotoma,</jats:italic> widely distributed in the Shizhuyuan mining area, were sampled. Biogeochemical and Number-Size fractal methods were used to evaluate the biogeochemical characteristics of trace elements in the samples and the feasibility of indicating subsurface mineral deposits. The results reveal that <jats:italic>D. dichotoma</jats:italic> not only has strong uptake of the active state of metal elements (Zn, Mo, Cd, Sn, etc.) in the soil, but also shows the geochemical anomalies of Zn, Fe, Tl, Ag, Pb, U, As, Bi, Cd, Mo and Sn in the study area. The Number-Size fractal method can effectively identify the concentration populations of biogeochemical target elements and obtain convincing anomaly thresholds. Analysis of the metal content of <jats:italic>D. dichotoma</jats:italic> is an effective tool for biogeochemical exploration of Pb-Zn-U hydrothermal deposits in the study area. Zinc as well as U are target elements, and Tl appears to be an effective pathfinder element for Zn-Pb-U mineralization. In addition, 260-340 m of Line 3 <jats:sup>#</jats:sup> and 1100-1200 m of Line 8 <jats:sup>#</jats:sup> are the key areas for future exploration of lead-zinc-uranium hydrothermal deposits. </jats:p>

<jats:p>To investigate the inter relationship of metal elements in soil-medicinal plant systems, 51 pairs of soil and Chinese herbaceous peony samples were collected from Bozhou City, China. Our results revealed that the major and trace elements in soils and Chinese herbaceous peony samples were in a similar descent order as: Al &gt; Fe &gt; Mn &gt; Cr &gt; Zn &gt; Cu &gt; Pb &gt; As &gt; Cd for soil samples, and Al &gt; Fe &gt; Zn &gt; Mn &gt; Cu &gt; Cr &gt; Pb &gt; As &gt; Cd for peony samples. The pollution indices of Enrichment factor (EF) and Nemerow integrated pollution index (NIPI) both indicated that Cr was the priority pollutant in soils and the other elements (Mn, As, Fe, Cd, Pb, Cu, and Zn) were slightly elevated. In general, the pollution load index (PLI) indicated that the studied soils were slightly contaminated by the nine elements. Furthermore, there existed significant relationship between Cr content in peony samples and Cr content in soils and soil pH (P &lt; 0.01), indicating that the main source of Cr in Chinese herbaceous peony was probably from soils. Additionally, Cr content in peony samples displayed the highest hazard quotient (HQ) value, followed by As, Cu, Al, Fe, Zn, Mn, Cd, and Pb. Although the hazard quotient (HQ) for all elements and hazard index (HI) were lower than 1, which indicated no adverse health effects for adults, it was necessary to strengthen the control of soil Cr content in the process of peony planting.</jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Geochemical processes related to mined, milled, or natural metal deposits collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits">https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits</jats:ext-link> </jats:p>

<jats:p> We describe a method for LA-ICP-MS elemental analysis of geological materials using low-dilution Li-borate fused glass WDXRF pellets, with samples, drift monitor, and 18 reference materials (RMs) identically prepared. After analysis for 46 elements by WDXRF, LA-ICP-MS intensities from samples and RMs are collected, and background corrected with <jats:italic>Iolite</jats:italic> software. <jats:italic>HALite</jats:italic> , a new software application, was developed to derive the elemental compositions from the LA-ICP-MS net signals. In <jats:italic>HALite</jats:italic> , elements are drift corrected using polynomial functions, and flux-fused RM element sensitivities are calculated from known mass fractions. Multiple internal standard (IS) elements are used to model each sample's laser response. Analyte mass fractions in unknowns are determined using the calibrated sensitivity correlation models for multiple IS elements. Either the WDXRF mass fractions or the initial round of calculated LA-ICP-MS mass fractions are used to calculate weighted mean sensitivities. Validation experiments with flux-fused RMs run as unknowns yield results with less than 5-10% total relative uncertainty for most analytes. We derive equations which allow calculation of the precision and total uncertainty as a function of mass fraction for each analyte element. </jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary materials:</jats:bold> Table 1 - RMs used; Table 2 - Operating parameters; Table 3 - Model vs. accepted mass fractions; Table 4 - NIST 610 vs. multiple IS models; Table 5 - Fitting parameters; Appendix 1 - HALite description; Appendix A - Summary calibration graphs; Appendix B - Validation results; Appendix C - WDXRF comparisons; Appendix D - Repeatability uncertainties; Appendix E - RM uncertainties; Appendix F - Total uncertainties for this article are available at <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.6084/m9.figshare.c.6639885">https://doi.org/10.6084/m9.figshare.c.6639885</jats:ext-link> </jats:p>

<jats:p>To meet the increasing demand for metals to assist in a successful and rapid energy transition, it is crucial to discover more first-class mineral deposits. With most of the world's major deposits occurring near surface, improved methods for detection at deeper levels are required.</jats:p> <jats:p>This paper summarizes the soil gas studies that have been published in English discussing the use of soil gas as a sample medium for mineral exploration. The potential and the reliability of various methods and gas species (O2/CO2, sulphur gases, polymetallic studies, gaseous hydrocarbons, radiogenic daughters (He, Rn), hydrogen and other gases) are reviewed and the challenges for the broad-scale adoption of soil gas measurement as an exploration tool are discussed.</jats:p> <jats:p>Soil gas composition has promising potential for mineral exploration, but much remains to be understood about the origins and processes affecting soil gas composition. There has been a great deal of variation among the studies in sampling and analytical techniques, targeted gas(es), targeted commodities and mineralization type, climatic conditions and environmental settings.</jats:p> <jats:p>Improvement is needed in technical consistency, systematic monitoring of the environmental factors shortly before and after sampling, and the impact of microbes on the composition of the gases. In addition, further study is needed into the impact of climate, the cover composition and structure as well as the biological impact of microbes and plant roots before soil gas composition is a reliable exploration method.</jats:p> <jats:p content-type="supplementary-material"> <jats:bold>Supplementary material:</jats:bold> <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" specific-use="dataset is-supplemented-by" xlink:href="https://doi.org/10.25919/5eww-8f16">https://doi.org/10.25919/5eww-8f16</jats:ext-link> </jats:p> <jats:p content-type="thematic-collection"> <jats:bold>Thematic collection:</jats:bold> This article is part of the Reviews in Exploration Geochemistry collection available at: <jats:ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="https://www.lyellcollection.org/topic/collections/reviews-in-exploration-geochemistry">https://www.lyellcollection.org/topic/collections/reviews-in-exploration-geochemistry</jats:ext-link> </jats:p>