Chemical Geology最新文献

{"title":"Petrogenesis of syenites at Phalaborwa, Kaapvaal Craton: (isotope) geochemical, modelling and age constraints","authors":"Robert Bolhar, Reza Maghdour-Mashhour, Lorenzo Milani, Suman Mondal, Gary J. O'Sullivan, Reiner Klemd, Qing Chang","doi":"10.1016/j.chemgeo.2025.123202","DOIUrl":"https://doi.org/10.1016/j.chemgeo.2025.123202","url":null,"abstract":"","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"56 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731852","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":"Bioapatite crystallinity and Rare Earth Element signatures in fossil and Recent sharks: A window into Past and Present seas","authors":"Luca Medici ,&nbsp;Annalisa Ferretti ,&nbsp;Alberto Collareta ,&nbsp;Giulia Bosio ,&nbsp;Giovanni Bianucci ,&nbsp;Giorgio Carnevale ,&nbsp;Simone Casati ,&nbsp;Simona Clò ,&nbsp;Luca Lanteri ,&nbsp;Federico Lugli ,&nbsp;Giuseppe Marramà ,&nbsp;Frederik H. Mollen ,&nbsp;Martina Savioli ,&nbsp;Daniele Malferrari","doi":"10.1016/j.chemgeo.2025.123200","DOIUrl":"10.1016/j.chemgeo.2025.123200","url":null,"abstract":"<div><div>The advent of biomineralization represented a key evolutionary innovation, enabling vertebrates to form skeletons and teeth made of bioapatite, a nanocrystalline apatite phase with variable chemical composition. This adaptability has driven vertebrate morphological diversity and ecological success. Bioapatite structure is shaped by metabolic processes, with ionic substitutions and vacancies influencing its crystallographic parameters. Major elements alter the <em>a</em> and <em>c</em> parameters of the bioapatite cell, while trace elements have minimal impact. Rare Earth Element (REE) signatures in fossil bioapatite, once considered direct proxies for paleo-seawater, may reflect complex diagenetic histories. This study examines bioapatite crystallinity and REE patterns in Recent and fossil catsharks (Scyliorhinidae <em>s.l.</em>) using μ-XRD and LA-ICP-MS. Recent teeth and scales of <em>Galeus melastomus</em> and <em>Scyliorhinus canicula</em> from the Italian coasts were tested and compared with fossil Eocene to Pliocene counterparts from strata across Europe. Our results underscore the value of crystallographic parameters in tracing both biological and <em>post-mortem</em> transformations in bioapatite. In particular, diagenetic processes led to organic matter loss and increased carbon incorporation, especially in tooth regions that were originally rich in organics. Fossil samples showed reduced <em>a</em> lattice parameters and unit cell volumes, increased <em>c</em> parameters, and enhanced crystallinity. Tooth crowns had higher crystallinity and volume than roots, reflecting lower organic contents. Crystallographic differences between scales and teeth suggest functional adaptations, with teeth exhibiting variable crystallite sizes for biomechanical efficiency. Diagenetic effects are seemingly independent of geological age, being rather influenced by depositional conditions and, possibly, by original physiological traits.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"702 ","pages":"Article 123200"},"PeriodicalIF":3.6,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731854","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":"Closure temperature for the fission-track systems","authors":"Matheus Rufino,&nbsp;Arnaldo Luis Lixandrão-Filho,&nbsp;Sandro Guedes","doi":"10.1016/j.chemgeo.2025.123195","DOIUrl":"10.1016/j.chemgeo.2025.123195","url":null,"abstract":"<div><div>We introduce a novel analytical equation (AE) for computing closure temperature (<span><math><msub><mi>T</mi><mi>c</mi></msub></math></span>) in fission-track (FT) systems, grounded in a rigorous physicochemical framework. By extending Dodson's foundational concept to the complex, non-first-order kinetics characteristic of fission-track annealing, this work overcomes historical barriers to a direct analytical formulation in FT thermochronology. To date, most <span><math><msub><mi>T</mi><mi>c</mi></msub></math></span> estimates for fission track systems have relied on numerical simulations based on the Principle of Equivalent Time (PET). However, a recently developed physicochemical framework allows modeling variable thermal histories without relying on PET. In this study, we employ this framework to construct an analytical equation for computing closure temperature in the fission-track system. The resulting <span><math><msub><mi>T</mi><mi>c</mi></msub></math></span> values are then compared with previously published results to assess accuracy and consistency. The analytical formulation is simpler, faster to compute, and more easily automated. However, the practical accuracy of this analytical solution is intrinsically linked to the quality and advancements of the empirical annealing models and bias models (track length to density relationships) upon which it relies.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123195"},"PeriodicalIF":3.6,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731859","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":"Effects of chemical weathering and grain size sorting on SrNd isotopic source rock signatures of river sediments in the lower Mekong River Basin: Implications for provenance studies","authors":"Pham Nhu Sang ,&nbsp;Zhifei Liu ,&nbsp;Yulong Zhao ,&nbsp;Pham Trung Hieu ,&nbsp;Sopheak Thav ,&nbsp;Sopheap Den","doi":"10.1016/j.chemgeo.2025.123199","DOIUrl":"10.1016/j.chemgeo.2025.123199","url":null,"abstract":"<div><div>Sr<img>Nd isotopic compositions are reliable proxies for tracing the provenance of riverine and marine sediments. However, these isotopic compositions can be influenced by processes such as chemical weathering in the source region and grain size sorting during transport, which can obscure the original provenance signals. In this study, Sr<img>Nd isotopic compositions of clay, silt, and sand fractions from river sediments in the Lower Mekong River Basin are analyzed to investigate the influence of chemical weathering and grain size sorting and their implications for provenance studies. Mainstream sediments exhibit higher ⁸⁷Sr/⁸⁶Sr (0.724) and lower ε_Nd (−9.72) values compared to tributary sediments (0.717 and − 5.61, respectively). The clay fractions in both mainstream and tributary sediments show more radiogenic ⁸⁷Sr/⁸⁶Sr (0.726) and higher ε_Nd (−7.29) values than the silt (0.721 and − 8.88, respectively) and sand (0.718 and − 9.27, respectively) fractions. Rb/Sr and ⁸⁷Sr/⁸⁶Sr in both mainstream and tributary sediments present moderate or strong correlations with K₂O/(CaO + Na₂O) and SiO₂/Al₂O₃, indicating that chemical weathering and grain size sorting moderately influence Sr isotopes. In contrast, Sm/Nd and ε_Nd display no or weak correlations with K₂O/(CaO + Na₂O) and SiO₂/Al₂O₃, suggesting that Nd isotopes are less affected by these factors. Despite these influences, significant differences in Sr<img>Nd isotopic compositions between mainstream and tributary sediments are evident, with moderate to strong negative correlations between ⁸⁷Sr/⁸⁶Sr and ε_Nd across clay, silt, and sand fractions. These differences effectively distinguish the mainstream from the tributary sediments, reflecting the control of source rock lithology and the preservation of source rock signatures in this region. To minimize the effects of chemical weathering and grain size sorting, this study recommends using Sr<img>Nd isotopic data from uniform grain size fractions for provenance investigations of riverine and marine sediments, with the silt fraction being the most suitable.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123199"},"PeriodicalIF":3.6,"publicationDate":"2025-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731853","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":"Viscosity and structure of Na2O-enriched haplogranitic melts: a DSC shift-factor calibration for peralkaline rhyolites","authors":"Veronica Stopponi ,&nbsp;Gabriele Giuliani ,&nbsp;Laura Calabrò ,&nbsp;Dmitry Bondar ,&nbsp;Sumith Abeykoon ,&nbsp;Claudia Romano ,&nbsp;Donald B. Dingwell ,&nbsp;Danilo Di Genova","doi":"10.1016/j.chemgeo.2025.123196","DOIUrl":"10.1016/j.chemgeo.2025.123196","url":null,"abstract":"<div><div>The influence of excess Na₂O on the structure, thermal properties and viscosity of haplogranitic melts was systematically investigated by integrating micropenetration viscometry, Raman spectroscopy (including Boson peak analysis) and differential scanning calorimetry (DSC).</div><div>This approach reveals fundamental structure-property relationships in these felsic melt analogs. We demonstrate that Na₂O-induced network depolymerization, clearly evidenced by Raman spectroscopy, provides a direct rationale for the observed dramatic, non-linear decrease in melt viscosity and a concurrent systematic increase in melt fragility.</div><div>Strong correlations are established between melt fragility and both nanoscale vibrational dynamics (Boson peak frequency, <span><math><mrow><msub><mi>ω</mi><mi>BP</mi></msub></mrow></math></span>) and macroscopic thermodynamics (configurational heat capacity change at the glass transition temperature, <span><math><mrow><mo>∆</mo><msubsup><mi>C</mi><mi>p</mi><mi>conf</mi></msubsup><mrow><mfenced><msub><mi>T</mi><mi>g</mi></msub></mfenced></mrow></mrow></math></span>), validating <span><math><mrow><msub><mi>ω</mi><mi>BP</mi></msub></mrow></math></span> and <span><math><mrow><mo>∆</mo><msubsup><mi>C</mi><mi>p</mi><mi>conf</mi></msubsup><mrow><mfenced><msub><mi>T</mi><mi>g</mi></msub></mfenced></mrow><mspace></mspace></mrow></math></span> as proxies for estimating melt fragility in experimentally challenging systems, such as those prone to nanostructuration. Furthermore, we provide DSC-viscosity shift factors <em>K</em>_{<em>onset</em>}<em>, K</em>_{<em>peak</em>}<em>, K</em>_{<em>endset</em>} applicable to peralkaline compositions. By addressing the role of thermal lag and thermal inertia in DSC analyses, our study refines the experimental accuracy of viscosity–temperature relationships and reinforces the robustness of the shift-factor approach across compositionally diverse silicate systems.</div><div>This work thus provides an integrated framework and predictive insights into the rheology of Na₂O-rich haplogranitic melts, relevant to understanding evolved magmatic systems.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"702 ","pages":"Article 123196"},"PeriodicalIF":3.6,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731858","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":"Calcium and copper isotope compositions in hydrothermally influenced sediments as proxies for hydrothermal activity on mid-ocean ridges: An example from the Carlsberg Ridge","authors":"Jian-Qiang Wang ,&nbsp;Shuang-Shuang Lyu ,&nbsp;Zhong-Yan Qiu ,&nbsp;Xi-Qiu Han ,&nbsp;Mou Li ,&nbsp;Chun-Feng Li ,&nbsp;Xue-Gang Chen","doi":"10.1016/j.chemgeo.2025.123197","DOIUrl":"10.1016/j.chemgeo.2025.123197","url":null,"abstract":"<div><div>As an essential product of hydrothermal activity, hydrothermally influenced sediments record source characteristics and geochemical signals of hydrothermal circulation. Here, we report on the chemical and isotopic compositions of a hydrothermally influenced sediment core (HiSC) and a biogenic carbonate sediment core (BcSC) collected near hydrothermal vents on the Carlsberg Ridge, northwest Indian Ocean. Episodic changes between metalliferous hydrothermal precipitates and calcareous sedimentation provide a unique opportunity to investigate the connection between calcium (Ca)-copper (Cu) isotope systems and hydrothermal activity. The δ^44/40Ca values (relative to NIST SRM915a) in HiSC ranged from 0.59 ± 0.10 ‰ (2SD) to 0.96 ± 0.09 ‰ and were controlled by the mixing between biogenic carbonates and detrital components (weathering product of host rock and/or sinking lithogenic particles). Endmember δ^44/40Ca of biogenic carbonates was 0.57 ± 0.07 ‰ (95 % confidence interval), consistent with the measured δ^44/40Ca range of BcSC (0.46 ± 0.12 ‰, 2SD, <em>n</em> = 8). Copper in HiSC showed δ⁶⁵Cu values (relative to NIST SRM976) of -0.03 ± 0.43 ‰ (2SD, <em>n</em> = 10), and was mostly supplied by hydrothermal inputs. The δ⁶⁵Cu of hydrothermal components in the sediments was calculated as −0.2 ± 0.1 ‰ (95 % confidence interval). Linking the Ca and Cu isotope systems we proposed a Ca<img>Cu index to semi-quantify the strength of hydrothermal activity of nearby vents. The hydrothermal activity was relatively strong at 9.8–11.8 ka and 7.4–7.8 ka, moderate at 9.0–9.8 ka, and weak at 7.8–9.0 ka. Modeling tests indicated that the Ca<img>Cu index is potentially a robust proxy for reconstructing hydrothermal history on mid-ocean ridges, despite practical application being limited by hydrothermal carbonate precipitation (e.g., at Lost City), secondary diagenetic alteration, and variations in endmember δ⁶⁵Cu values. Furthermore, our study indicated that isotopically light sources/processes are required to counterbalance the preferential removal of light Ca isotopes from seawater by marine sediments. Hydrothermal inputs eventually contribute Cu with positive δ⁶⁵Cu values (or even higher than the seawater value) to the ocean.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123197"},"PeriodicalIF":3.6,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731860","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":"The glass transition and non-Arrhenian viscosity of extremely depolymerized silicate melts","authors":"Thilo Bissbort ,&nbsp;Kai-Uwe Hess ,&nbsp;Elena Sturm ,&nbsp;Sebastian Sturm ,&nbsp;Detlef Rogalla ,&nbsp;Ralf Dohmen ,&nbsp;Knut Müller-Caspary ,&nbsp;Donald B. Dingwell","doi":"10.1016/j.chemgeo.2025.123193","DOIUrl":"10.1016/j.chemgeo.2025.123193","url":null,"abstract":"<div><div>Properties of extremely depolymerized melts and glasses have always been elusive due to their inaccessibility in experiments. Information on viscosity, for example, was previously restricted to very high temperatures. Yet, theory and experimental details about peridotites suggest that highly depolymerized melts exhibit exceptional properties, such as extremely non-Arrhenian viscosity-temperature relationships. Studies at low temperatures, i.e., just above the glass transition temperature, required for investigating such phenomena have been impossible for many compositions due to their rapid crystallization and thus extremely poor glass-forming ability. Here, we have developed a novel method combining synthesis by pulsed laser deposition with characterization by fast differential scanning calorimetry (FDSC) to deposit glassy thin films, from a plasma directly onto FDSC sensors, combined with calorimetric analysis at very high heating-cooling rates (3500–9500 °C s⁻¹). In this way we have been able to explore the glass transition of the glasses (at or near olivine stoichiometry): Mg_1.30SiO_3.3, Fe_0.34Mg_1.67SiO_4.0, Fe_0.49Mg_1.53SiO_4.0, Fe_1.21Mg_0.91SiO_4.1, and Fe_2.26SiO_4.3. The peak glass transition temperature at 5000 °C s⁻¹ increases from 550 °C for Fe_2.26SiO_4.3 with decreasing (Fe + Mg)/Si and with increasing Mg/(Fe + Mg) to 736 °C for Mg_1.30SiO_3.3. Viscosities derived through the shift factor approach range from 10^5.61 to 10^6.04 Pa∙s in that temperature range. These results thus extend the experimentally available viscosity range by ca. seven log units and were employed here, together with high-temperature superliquidus viscosity data to fit the Vogel-Fulcher-Tammann (VFT) equations for these melts. The viscosity-temperature relationships are all strongly non-Arrhenian (m = 82–123 ± 15). We provide a comparison with other experimental studies of ultrabasic melts and with predictions from viscosity models. The inability of the latter to predict the observed viscosities highlights the necessity of direct experimental studies such as that presented here.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123193"},"PeriodicalIF":3.6,"publicationDate":"2025-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145732117","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":"Inverse methods for extracting seasonality signals from ungulate tooth enamel","authors":"Alexandra L. Norwood ,&nbsp;Daniel R. Green ,&nbsp;Briana L. Pobiner ,&nbsp;J. Tyler Faith","doi":"10.1016/j.chemgeo.2025.123191","DOIUrl":"10.1016/j.chemgeo.2025.123191","url":null,"abstract":"<div><div>The variability in the isotopic composition of tooth enamel recorded in serially-sampled ungulate teeth provides a valuable archive of changes in the food and water consumed by an animal on the temporal scale of months to years. These records provide evidence of paleoseasonality and insight into animal behavior and ecology over seasonal temporal scales relevant to selection. However, interpreting these records proves difficult due to the complex nature of enamel mineralization, which variably compresses, lengthens, and dampens the input isotopic signal during growth. Despite these complications, “inverse modeling” can recover original input signals from serial chemical measurements in teeth, by modeling enamel mineralization and the incorporation of mineral content with specific isotopic compositions through time. Here we present a set of models to execute this process, which fit the enamel mineralization patterns of plains zebra (<em>Equus quagga</em>) but are parameterized to be adaptable to the growth patterns of other mammalian teeth. Through sensitivity testing and the application of the inverse model to real-world data from modern plains zebra from Ol Pejeta Conservancy in central Kenya, we show that these models recover an accurate seasonality signal from preserved enamel, particularly closer to the coronal end of the crown and over longer seasons (i.e., longer periodicities). These models are a valuable expansion of the existing toolkit for the analysis of enamel isotope data as a paleoecological proxy.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123191"},"PeriodicalIF":3.6,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689932","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":"Internally consistent thermodynamic properties of Nd chloride aqueous species and Nd3+ derived from hydrothermal solution calorimetry at 25–150 °C","authors":"Yerko Figueroa Penarrieta ,&nbsp;Alexander P. Gysi","doi":"10.1016/j.chemgeo.2025.123192","DOIUrl":"10.1016/j.chemgeo.2025.123192","url":null,"abstract":"<div><div>Rare earth elements (REE) are important critical elements used in the high-technology and green energy industries. Hydrothermal fluid-rock interaction and the stability of aqueous chloride complexes play an important role in the mobilization and deposition of REE in geologic systems. Geochemical modeling can be used to interpret the mobility of REE in these hydrothermal fluids. However, the accuracy of modeling predictions strongly depends on the underlying thermodynamic properties for REE aqueous species. In this study, hydrothermal solution calorimetry was used to measure the standard partial molal enthalpy of solution (Δ_sol<em>H</em>°) of Nd chloride solid (NdCl₃·6H₂O) from 25 to 150 °C in order to determine the standard thermodynamic properties of Nd chloride aqueous species. The experiments were conducted in aqueous hydrochloric acid-based aqueous solutions with an initial pH of 2 and varying ionic strength (0.08–0.42 mol/kg), at which conditions the Nd³⁺ and Nd chloride species are both stable. In the studied temperature range, the measured Δ_sol<em>H</em>° values differ by 35 kJ/mol in comparison to thermodynamic predictions based on available literature data. These large discrepancies have important implications for geochemical modeling because the thermodynamic properties of REE aqueous species are derived from the properties of REE chloride solids. To address this problem, the standard enthalpy of formation (Δ_f<em>H</em>°) of NdCl₃·6H₂O(s) and aqueous NdCl²⁺ species were optimized to reproduce the experimentally derived Δ_sol<em>H</em>° values and keeping internal consistency with the recently updated thermodynamic properties of Nd³⁺. The outcome of this study permits deriving a set of recommended internally consistent thermodynamic properties for the Nd aqueous species which improve thermodynamic modeling of REE mobilization in acidic NaCl-bearing aqueous fluids.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123192"},"PeriodicalIF":3.6,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145690055","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":"Rapid recycling of sediment-derived granites in accretionary orogens: Implications from the Alataw Mountains, NW China","authors":"Jiyuan Yin ,&nbsp;He Huang ,&nbsp;Ilya Bindeman ,&nbsp;Chiara Maria Petrone ,&nbsp;Mike Fowler ,&nbsp;Andrew C. Kerr ,&nbsp;Zaili Tao ,&nbsp;Tao Wang ,&nbsp;Min Sun ,&nbsp;Guochun Zhao ,&nbsp;Wenjiao Xiao","doi":"10.1016/j.chemgeo.2025.123181","DOIUrl":"10.1016/j.chemgeo.2025.123181","url":null,"abstract":"<div><div>The origin of S- and I-type granites in accretionary orogens remains contentious due to complex geochemical and isotopic signatures, challenging traditional granite classifications. We present new zircon U-Pb-Hf-O, quartz O isotope and whole-rock geochemical data from two-mica (S-type) and biotite (nominally I-type) granites in the Alataw Mountains, northwest China, showing both are derived from sediment-dominated protoliths. Zircon U<img>Pb dating indicates emplacement at 303–298 Ma, with differing inherited ages of 443–397 Ma and 1404–811 Ma. The two-mica granites were derived from metapelitic sources and are strongly peraluminous, while the biotite granites are metaluminous to weakly peraluminous with many “I-type” characteristics. Both types exhibit high SiO₂, low MgO, elevated zircon δ¹⁸O, high quartz δ¹⁸O and high Δ^’17O values consistent with sedimentary sources, but depleted εNd(t) and εHf(t) values that require a juvenile origin. Phase equilibrium modelling indicates that these granites formed through water-fluxed partial melting of variable Carboniferous sedimentary rocks. Thus, crustal melts appear juvenile and S-type granites appear to be I-type. Our findings highlight the critical role of rapid crustal recycling via sediment melting during the reworking of juvenile crust within arc-related accretionary orogens and suggest the need for caution when considering granite origins based on traditional typological classifications.</div></div>","PeriodicalId":9847,"journal":{"name":"Chemical Geology","volume":"701 ","pages":"Article 123181"},"PeriodicalIF":3.6,"publicationDate":"2025-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145690052","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}