Acta Geochimica最新文献

{"title":"Critical processes controlling the formation of visible gold in the giant Jiaodong gold province: Constraints from microtextural and geochemical analyses by SEM, TOF–SIMS, and LA-(MC)-ICP-MS","authors":"Hong Wang,&nbsp;Ting-Guang Lan,&nbsp;Lang-Ye Zhao,&nbsp;Hong-Rui Fan,&nbsp;Zhan-Ping Li,&nbsp;Huan-Long Hu,&nbsp;Zi-Qi Xu,&nbsp;Hong-Wei Peng,&nbsp;Lei Shu","doi":"10.1007/s11631-025-00833-3","DOIUrl":"10.1007/s11631-025-00833-3","url":null,"abstract":"<div><p>The world-class Jiaodong gold province in the North China Craton hosts over 5000 t of Au resource and is characterized by abundant visible gold mineralization. However, the critical processes controlling the formation of visible gold in this province remain poorly understood. To solve this problem, integrated microtextural, trace elemental, and sulfur isotopic analyses of pyrite from the high-grade Linglong gold deposit in the Jiaodong gold province were conducted in this study. Two distinct pyrite types were identified within auriferous quartz-sulfide veins: (1) Py1 aggregates in quartz-pyrite veins (hydrothermal stage II), and (2) euhedral to subhedral, coarse-grained Py2 crystals in quartz-polymetallic sulfide veins (hydrothermal stage III). Microtextural and elemental analyses revealed that visible gold predominantly occurs as intergranular particles between primary pyrite crystals within Py1 aggregates. The Py1 exhibits complex microtextures with abundant mineral inclusions of polymetallic sulfides and has low concentrations of Au (median: 0.032 ppm) with a narrow <i>δ</i>³⁴S range (4.86‰–6.75‰), indicative of rapid crystallization under unstable, disequilibrium conditions. By contrast, the Py2 is texturally homogeneous and contains higher Au concentrations (median: 0.304 ppm) with progressively increasing <i>δ</i>³⁴S values (5.25‰–10.14‰) over time, suggesting slow crystal growth under more stable, near-equilibrium conditions. Based on the microtextural and geochemical information, it is proposed that fluid boiling occurred only during the hydrothermal stage II, which resulted in the unstable physicochemical environment and rapid deposition of gold. During the boiling processes, gold colloids likely occurred and promoted the formation of visible gold.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1167 - 1185"},"PeriodicalIF":1.3,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentary petrology and geochemistry of the siliciclastic rocks from the Isparta Angle area (SW Türkiye): Implications for provenance and tectonic settings","authors":"Hakan Çoban,&nbsp;Ömer Elitok,&nbsp;Süleyman Polat,&nbsp;Şemsettin Caran","doi":"10.1007/s11631-025-00829-z","DOIUrl":"10.1007/s11631-025-00829-z","url":null,"abstract":"<div><p>The Antalya Complex within the Isparta Angle (IA) in the southwest of Türkiye includes various rock types formed in different geodynamic settings and contains important data that shed light on the geodynamic evolution of the Eastern Mediterranean region. In this study, source rocks and tectonic settings of ancient sedimentary basins within the IA have been interpreted using geochemical contents of siliciclastic rocks in different ages. In this regard, whole-rock major, trace and rare earth element (REE) analyses have been conducted on the Cenozoic turbiditic sandstones (from the Eocene Isparta Formation and the Miocene Güneyce Formation in the north of the IA) and integrated with the available data of the Triassic shales from the east and Upper Cretaceous sandstones from the southwest of the IA. The results indicate that Cenozoic sandstone samples are calcium-rich (CaO, 30.54–43.87 wt%, average 37.63 wt%), comparable to those of Upper Cretaceous sandstones (CaO, average 24.92 wt%) and Late Triassic (CaO, range between 11.27–26.71 wt%) shales. They demonstrate an excellent carbonate dilution effect on the majority of major oxides. In contrast to the Late Triassic shales with close affinity to Post-Archean Average Archean Shale (PAAS), Cenozoic and Upper Cretaceous ophiolite-related clastic sediments display strike depletions in Nb–Ta, Th, Rb, Zr and Hf and enrichments in Ni, Co and Cr, suggesting mafic and ultramafic rocks in a source region. Notable enrichments of Cr (average 80.5 ppm), V (average 105.5 ppm), Ni (average 42.3 ppm) and Co (average 13.9 ppm) in Late Triassic shales can be attributed to the influences of Triassic OIB-like basaltic rift magmatism in their source regions. In general, their igneous source rocks were derived from mixed sources, e.g., (1) predominantly continental felsic and lesser rift-related basaltic mafic source rocks for Late Triassic shales, (2) mainly ophiolitic mafic-ultramafic and lesser continental felsic source rocks for Upper Cretaceous sandstones and (3) primarily continental felsic and lesser ophiolitic mafic-ultramafic source rocks for Cenozoic sandstones. These inferences also imply that the distinct parent rock compositions of the Late Triassic, Upper Cretaceous and Cenozoic aged siliciclastic rock samples reflect their distinct tectonic settings such as the passive rift setting of Late Triassic shales, an SSZ setting for the Upper Cretaceous sandstones and a collisional setting of the Cenozoic sandstones, respectively.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 2","pages":"357 - 383"},"PeriodicalIF":1.3,"publicationDate":"2025-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147735052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geochemical signatures and petrogenesis of intraplate dolerite dykes in the Salem block, Southern Granulite Terrane, India: Evidence of arc and MORB affinities","authors":"Chandran Ramachandran,&nbsp;Arisiappan Thirunavukkarasu,&nbsp;Rangaraj Ravi,&nbsp;Tamilarasi Sathyamurthy Kavin,&nbsp;Sureshkumar Shrivarsan","doi":"10.1007/s11631-025-00830-6","DOIUrl":"10.1007/s11631-025-00830-6","url":null,"abstract":"<div><p>This study provides geochemical signatures of dolerite dykes to unravel their tectonic settings and petrogenesis. The dykes were emplaced in the Southern Granulite Terrane, south India, which was accreted to the Dharwar craton. The Salem block has numerous mafic dykes, which are widespread within the high-grade rocks, in particular Salem dolerite dykes, which have four predominant orientations (NNW–SSE, NE–SW, NW–SE, N–S) located in the Attur, Mettur and Yercaud regions. Two geochemical groups of dolerite dykes are identified by their geochemical characteristics, which are (low to medium potassium content) tholeiitic in nature plotted in a sub-alkaline field consisting of basalt and basaltic andesite. The quartz normative basaltic composition of dolerites with Fe enrichment is found in the Attur region, while the Mg-rich basaltic andesitic composition of dolerites is found in the other two regions and one dyke in the Attur region. The fractionation of pyroxene and plagioclase can be inferred using the high-field-strength elements (HFSEs). The positive enrichment of Cs, U, K, Pb and Nd, and negative Nb, P, Zr, Ti and Y anomalies in a primitive normalized diagram and enriched light rare earth elements (LREEs)/large-ion lithophile elements (LILEs) and flat heavy rare earth elements (HREEs) with little or no anomalies of Eu values in the chondrite-normalized pattern resemble arc-related basalts, which represent potential contamination of crust resulting from partial melting of magma. The two distinguishable mafic emplacements in the study reveal two possible magmatic origins that may form in different periods in a regional stress intraplate extension caused by post-collisional arc and mid-ocean ridge basalt (MORB)-related tectonic settings. The petrogenetic models indicate that the dykes were intruded from the shallow part of the magma from the non-plume spinel-lherzolite field.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 3","pages":"767 - 788"},"PeriodicalIF":1.3,"publicationDate":"2025-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148196303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Barium transport and isotopic fractionation in plants","authors":"Shuming Xu,&nbsp;Congcong Cao,&nbsp;Chao Xiong,&nbsp;Hairun Wang,&nbsp;Ziqian Qiao,&nbsp;Kai Li,&nbsp;Yingzeng Gong,&nbsp;Huimin Yu","doi":"10.1007/s11631-025-00825-3","DOIUrl":"10.1007/s11631-025-00825-3","url":null,"abstract":"<div><p>Excess barium (Ba) in soil can result in Ba over-enrichment in crops, which may adversely affect human health. However, the transport and isotopic fractionation of Ba in plants remain poorly understood. We analyzed the Ba content and isotopic composition of three crops (rice, pak choi, and maize) grown in Ba-contaminated soil. Results for rice and maize demonstrated significant fractionation and environmental sensitivity in the transport of Ba, and longer flooding durations were found to increase Ba accumulation in rice grains during the filling stage. In contrast, research on pak choi revealed limited fractionation and strong uptake and transport of Ba. The estimated daily intake of Ba in the edible portion of pak choi (stems and leaves) was 15–24 times the recommended daily intake of 0.2 mg/kg body weight per day. Therefore, pak choi was the least suitable crop for Ba-contaminated areas. This study provides new insights into how Ba isotopic fractionation can trace Ba transport in crops, offering practical applications for food safety and environmental monitoring.</p><h3>Graphical abstract</h3>\u0000<div><figure><div><div><picture><source><img></source></picture><span>The alternative text for this image may have been generated using AI.</span></div></div></figure></div></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 2","pages":"331 - 341"},"PeriodicalIF":1.3,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147735037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring rare earth elements in Northern Kazakhstan: The potential of ion-adsorption clays and coals as unconventional sources","authors":"Medet Junussov,&nbsp;Maxat K. Kembayev,&nbsp;Manshuk Kokkuzova,&nbsp;Akmaral Baisalova,&nbsp;Zamzagul T. Umarbekova,&nbsp;Rustem Abirov,&nbsp;Sayat Erbolatuly Rais,&nbsp;Abylay Amantayev","doi":"10.1007/s11631-025-00828-0","DOIUrl":"10.1007/s11631-025-00828-0","url":null,"abstract":"<div><p>This study presents the first integrated mineralogical and geochemical investigation of unconventional rare earth elements (REEs) in ion-adsorption clay (IAC) from the weathered granitic complex of Souktal and coal-derived samples from Saradyr and Bogatyr mines in Kazakhstan. Six representative samples were analyzed using mineralogical, geochemical, and petrographic methods, along with CIA/CIW (chemical index of alteration/weathering), and elemental ratios to assess weathering intensity and provenance. Results show that REEs in IAC samples are primarily adsorbed onto kaolinite and likely apatite under mildly acidic conditions (pH 4.8–5.0), with high CIA/CIW values (&gt; 93.2) indicating advanced weathering. In coal ash, REEs are mainly hosted in organic matter and phosphate minerals, showing a strong correlation with organic carbon, while CIA/CIW values (&gt; 62.8) indicate moderate to high weathering intensity. Provenance analysis indicates felsic sources for IAC and mixed mafic–intermediate for coal-derived samples. Although Coutl values (1.1–1.7) are promising, total REEs concentrations remain below 10 ppm, suggesting subeconomic potential. The findings reveal that all samples from the studied deposits are characterized by high weathering under arid climatic conditions, exhibiting an enrichment pattern similar to underdeveloped global analogs. This reflects a complex interplay between weathering intensity, regolith development, coalification dynamics, sediment source, hydrology, and organic-phosphate host phases in controlling REEs distribution. REEs enrichment in both IAC-type and coal-hosted deposits is influenced by arid-zone supergene processes and coastal plain diagenetic pathways. Future research should target deeper weathered regoliths in IAC systems and surrounding coal seam rocks, using advanced analytical and stratigraphic tools to clarify REEs speciation and the influence of paleoclimate and tectonics on their accumulation in North Kazakhstan.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 5","pages":"1390 - 1412"},"PeriodicalIF":1.4,"publicationDate":"2025-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149098763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"C-V fractal modeling of the pyrite thermoelectric coefficient and estimation of continuation of ore bodies at depth in the Pujon gold deposit, DPR Korea","authors":"Yon-Ho Kim,&nbsp;Chung-Nam O,&nbsp;Kwang-U Choe,&nbsp;Kwang-Chol Hwang","doi":"10.1007/s11631-025-00824-4","DOIUrl":"10.1007/s11631-025-00824-4","url":null,"abstract":"<div><p>This paper describes a method for estimating the continuation of ore bodies at depth based on concentration-volume (C-V) fractal modeling of the pyrite thermoelectric coefficient in the Pujon gold deposit, Democratic People’s Republic of Korea. The method is first established using data in the Kumjomdong area, a well-explored brownfield, and it is then applied to estimate the continuation of ore bodies at depth in the Pyongsandok area, a less-explored greenfield. The methodology consists of four steps: (1) 3D modeling of ore bodies using surface geological mapping, mining tunnels in different levels, and a borehole dataset; (2) 3D modeling of thermoelectricity coefficients from Au-bearing pyrites based on discrete smooth interpolation and C-V fractal techniques; (3) determination of levels used for calculation of the thermoelectric parameter of pyrite by C-V fractal modeling instead of traditional levels; and (4) determination of the thermoelectric parameter vertical gradient of pyrite reflecting the variation characteristics of pyrite thermoelectricity in the Pujon deposit. The results indicate that (1) pyrites in the Pujon deposit are dominantly P-type, and it is not reasonable to use traditional levels to calculate the thermoelectric parameter of pyrite; (2) thresholds determined by C-V fractal modeling can be used as levels to calculate the thermoelectric parameter of pyrite; (3) the thermoelectric parameter vertical gradient of pyrite ranges from 1 to 2 in the Pujon deposit; and (4) ore body Pyongsan No. 9 extends 85 m to 235 m downward from the current borehole location.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1377 - 1394"},"PeriodicalIF":1.3,"publicationDate":"2025-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated study of the deformed phosphorite dolomite of the Early Cambrian Sirban formation in the Lesser Himalayas, Pakistan","authors":"Khawaja Umair Majeed,&nbsp;Muhammad Saleem Mughal,&nbsp;Xijuan Tan,&nbsp;Sara Criniti,&nbsp;Massimo Civitelli,&nbsp;Muhammad Rustam Khan,&nbsp;Shoukat Hussain Khan,&nbsp;Salvatore Critelli","doi":"10.1007/s11631-025-00823-5","DOIUrl":"10.1007/s11631-025-00823-5","url":null,"abstract":"<div><p>Phosphorite deposits in tectonically active regions present complex mineralogical and geochemical signatures due to post-depositional alteration. This study investigates the highly deformed Cambrian age phosphorite dolomite unit within the Sirban Formation of the Lesser Himalayas, Northern Pakistan, to understand its genesis, deformation history, and economic potential. Using integrated field observations, petrography, SEM–EDS, XRD, XRF, and ICP-MS analyses, the study documents the effects of intense brittle deformation along the Garlanian and Tarnawai thrust faults. Numerous quartz veins and iron oxide staining suggest active post-depositional hydrothermal fluid flow. The mineral assemblage is dominated by apatite, dolomite, quartz (micro- to cryptocrystalline), pyrite, hematite, magnetite, and chalcedony, with textural evidence of multiphase phosphate formation. SEM imaging confirmed chert and chalcedony overprints, while EDS and XRF analyses revealed high Ca and P concentrations indicative of apatite. XRD confirmed both hydroxyl-apatite and fluorapatite phases. Geochemical proxies including Co/Zn ratios (&gt; 0.5) and V/(V + Ni) suggest a dominantly reducing, hydrothermal depositional environment, although a negative Ce anomaly (<i>δ</i>Ce = 0.68) implies oxidizing conditions during early phosphogenesis. Rare earth element analysis (ΣREEs + <i>Y</i> = 503.16 µg/g) showed strong light (L)REE enrichment, with economic evaluations using REE_def and <i>K</i>_outl (avg. 0.96) highlighting its potential as a critical REE resource. The deposit’s average P₂O₅ content of 28.33% classifies it as furnace grade, with beneficiation potential to upgrade it to acid grade. These findings support the Sirban Formation as a promising target for future phosphate and REE exploitation in the region.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 5","pages":"1440 - 1460"},"PeriodicalIF":1.4,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149099147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fe isotopes in sulfides in the Aguas Zarcas (CM2) chondrite: Implications for the history of the parent asteroids","authors":"Xinqian Zhu,&nbsp;Xinyu Wang,&nbsp;Cheng Qian,&nbsp;Kexin Deng,&nbsp;Qi He,&nbsp;Zaicong Wang,&nbsp;Wen Zhang,&nbsp;Ao Yang,&nbsp;Fabin Pan,&nbsp;Xiang Wu","doi":"10.1007/s11631-025-00821-7","DOIUrl":"10.1007/s11631-025-00821-7","url":null,"abstract":"<div><p>CM chondrites contain valuable insights into the formation and evolution of the solar nebula, as well as the secondary aqueous alteration processes that affected their parent bodies. Our study focuses on primary and secondary sulfides within the Aguas Zarcas (CM2) chondrite, investigating their formation mechanisms based on their morphology, textures, and compositions. Moreover, we infer the formation temperatures of the sulfides from 230 to 500 ℃ for primary and from 100 to 135 ℃ for secondary. We select representative grains and conduct Fe isotope measurements on them. The primary sulfides with <i>δ</i>^56/54Fe ranging from − 2.44‰ to + 0.69‰ are associated with sulfide–silicate melt segregation, while secondary sulfides with <i>δ</i>^56/54Fe values between − 1.83‰ and − 0.14‰ are linked to aqueous alteration. Overall, the Ni content of the grains is positively correlated with <i>δ</i>^56/54Fe. It might be related to the changes in crystal structure and chemical bond lengths due to the increase in nickel content. Fe isotopes provide a new perspective on sulfide formation and the evolution of a carbonaceous chondrite parent body.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 1","pages":"42 - 54"},"PeriodicalIF":1.3,"publicationDate":"2025-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146091025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Light elements in the Martian core","authors":"Yinfang Yang,&nbsp;Shuangmeng Zhai","doi":"10.1007/s11631-025-00819-1","DOIUrl":"10.1007/s11631-025-00819-1","url":null,"abstract":"<div><p>The Martian core mainly contains iron, nickel and some light elements. However, controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data. Recently, the InSight lander collected long-term marsquake data, which improved the Martian interior structure model. Based on the preliminary analysis of marsquake data, Mars has a molten liquid core with a radius of around 1700 km. As the Martian core has a smaller density and lower temperature than pure iron at corresponding pressure and temperature conditions, some light elements are introduced to reduce the density and liquidus temperature. With various methods for seismic analysis, in-situ high-pressure and high-temperature experiments, and first-principal calculations, the Martian core composition and evolution models have been updated in the past few years. Here, we review those studies on the light elements in the Martian core from four aspects including (1) high-temperature and high-pressure experiments, (2) marsquake data, (3) mineral physics model with molecular dynamics simulations and (4) cosmochemistry investigation. We discussed the effect of different light elements on the Martian core’s density, sound velocity and liquidus temperature. Moreover, the review examines the varieties, abundances and forms of light elements in the Martian core.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"45 1","pages":"1 - 14"},"PeriodicalIF":1.3,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genesis of the Heima zinnwaldite deposit in the Gongshan region, Southeast Tibetan plateau","authors":"Shiping Li,&nbsp;Zechuan Wang,&nbsp;Jing Wang,&nbsp;Zhen Jia,&nbsp;Jialong Cheng,&nbsp;Fuchuan Chen,&nbsp;Shiyin Xiao,&nbsp;Chaofang Dong,&nbsp;Yitian Luo","doi":"10.1007/s11631-025-00822-6","DOIUrl":"10.1007/s11631-025-00822-6","url":null,"abstract":"<div><p>The middle-scale Heima zinnwaldite deposit is situated in the southeastern Tibetan Plateau, SW China. The NNW- to NS-trending orebodies are hosted in the Gaoligongshan metamorphic zone. To clarify the zinnwaldite genesis at Heima, this study presents an integrated investigation of the Heima pegmatites, combining precise geochronology, isotopic tracing, and detailed mineral chemistry to constrain its formation age, petrogenetic origin, and mineralization processes. Our robust geochronological framework, employing magmatic zircon (56.93 ± 0.53 Ma) and cassiterite (57.0 ± 4.2 Ma), establishes the pegmatite emplacement during the Late Paleocene to Early Eocene, representing the maximum age of lithium mineralization. Hf isotopic compositions (<i>ε</i>Hf_(t) =  −14.3 to −12.4) demonstrate that the Heima pegmatite originated from remelting of ancient sediments, distinguishing it from contemporaneous Eocene Gangdese–Tengchong granites (<i>ε</i>Hf_(t) =  −12.7 to +11.0) that show mantle contributions. This crustal signature aligns with the evolutionary trend of Hf isotopes in regional gneissic granites (600−420 Ma), supporting an anatectic origin from ancient continental crust rather than being derivatives of nearby Eocene granitic plutons. Detailed geochemical analysis of Li-micas reveals two distinct generations with contrasting formation mechanisms. The primary mica-Ia (53.45 ± 0.86 Ma, Rb–Sr age) exhibits extreme incompatible element enrichment (Li, Be, Rb, Cs) and remarkably low K/Rb ratios (3.98–4.37), characteristic of crystallization from highly fractionated granitic melts. In contrast, secondary mica-Ib and mica-II (17.9–16.0 Ma, Rb–Sr age) show significant Nb–Ta–W enrichment, reflecting precipitation from F–P-rich hydrothermal fluids during Miocene metamorphic–hydrothermal events. Principal component analysis (PCA) confirms the compositional disparity between these mica generations, with the later phases attributed to fluid-induced alteration and reworking. Regional correlation identifies two distinct lithium mineralization episodes in the Gongshan area, southeast Tibetan Plateau. The Eocene phase (~ 55 Ma) is zinnwaldite-dominant (e.g., Heima, Puladi), associated with crustal melting following Neo-Tethyan closure. The Miocene phase (~ 17 Ma) is spodumene-dominant (e.g., Danzhu, Peili), linked to Himalayan leucogranites formed as the rapid exhumation, denudation, and decompression partial melting of Himalayan Crystalline Complex.</p></div>","PeriodicalId":7151,"journal":{"name":"Acta Geochimica","volume":"44 6","pages":"1352 - 1376"},"PeriodicalIF":1.3,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145646207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}