Ore Geology Reviews最新文献

{"title":"Is there a specific “timing of mineralization” in gold deposits?","authors":"Wendell Fabricio-Silva ,&nbsp;Maria Emilia Schutesky ,&nbsp;Hartwig E. Frimmel ,&nbsp;Denis Fougerouse ,&nbsp;Carlos A. Rosière ,&nbsp;Fabricio A. Caxito ,&nbsp;Alice Bosco-Santos","doi":"10.1016/j.oregeorev.2025.106663","DOIUrl":"10.1016/j.oregeorev.2025.106663","url":null,"abstract":"<div><div>Mineral chemistry, stable isotope geochemistry, deformation microstructures, and compositional zoning are keys to unravel the mineralization history of gold-bearing sulfide assemblages. As such, textural and compositional domains can represent (i) primary mineralization processes associated with crystallization and (ii) processes related to remobilization. Growth zonation can mark both fluid-rock interaction and the crystallization kinetics of sulfides, with implications on the oscillatory distribution of gold therein. For the latter, intra-grain migration of elements in the sulfide crystal structure can be attributed to several mechanisms and sub-mechanisms. Recognizing and distinguishing which mechanisms are responsible for the observed sulfide texture requires micro- to nanometer-scale spatial resolution analytical techniques. Such techniques can discern between several episodes of Au-bearing sulfide crystallization and remobilization, each contributing to highly different proportions of the overall gold budget. Thus, these mechanisms influence whether, how, and when gold is concentrated and consequently, they are key to our understanding of the effective “timing of gold mineralization.” By way of examples, we define a conceptual framework of how the intracrystalline transfer mechanisms of Au (and that of other metals) can inform about the history of a given deposit. An important outcome of this holistic exercise is that mineralization often cannot be ascribed to a single, well-defined event but reflects protracted episodes of mineral growth and remobilization.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106663"},"PeriodicalIF":3.2,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143941911","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 mineralogy and geochemistry of skarn minerals from the Lalangmai W deposit in the East Kunlun Orogen, China and its comparision with the Baiganhu w-sn deposit: Implication on regional metallogenesis","authors":"Fei Teng ,&nbsp;Yongbao Gao ,&nbsp;Huanhuan Wu ,&nbsp;Leon Bagas ,&nbsp;Yuxiang Teng ,&nbsp;Wendi Guo ,&nbsp;Shaoyong Jiang ,&nbsp;Jiangwei Zhang ,&nbsp;Kan Li ,&nbsp;Delong Jing ,&nbsp;Zhenyu Ma","doi":"10.1016/j.oregeorev.2025.106662","DOIUrl":"10.1016/j.oregeorev.2025.106662","url":null,"abstract":"<div><div>East Kunlun Orogen (EKO) hosts numerous economically important deposits in western China, including the Baiganhu W-Sn deposit in the west and the Lalangmai W-only deposit in the east, which share similar geological characteristics. However, significant differences exist between the two deposits, which include the decoupling of W and Sn mineralisation and the smaller size of the mineralisation at Lalangmai compared to Baiganhu. These differences reflect contrasting magmatic and fluid evolution histories and offer a valuable opportunity to refine models for the W-Sn metallogenesis in the EKO. In this contribution, we present a comprehensive study of the geochemistry and mineralogy of garnet, diopside and scheelite from the Lalangmai W deposit, supplemented by published data on petrology and isotopic geochemistry of monzogranite. The data are further compared with those of Baiganhu to better illustrate nature of the geological bodies. The results suggest that the differences between the two areas can be largely attributed to variations in the nature of the granitic rocks. The Lalangmai granites are characterised by lower temperature of emplacement, the absence of biotite and are relatively enriched Sr-Nd isotopic signature compared to the Baiganhu granites. In addition, the prevalence of Al-rich garnets in the peraluminous, felsic, ilmenite-bearing intrusions at Lalangmai contrasts with the Fe-rich garnets related to alteration in the Baiganhu area. This mineralogical distinction possibly suppresses the deposition of Sn and W mineralisation at Lalangmai, given that Sn substitutes for Fe, which represents the principal mechanism of deposition. Furthermore, a lack of oscillatory zoning in garnet and scheelite, a more uniform REE pattern of scheelite, and the prevalence of Mo-elevated only scheelite indicate a relatively stable redox environment and felsic environment. The single-stage mineralisation during prograde phase, as opposed to fluid circulation and multi-phase interactions, further restrict the scale of the deposit. These findings highlight a spatial and genetic decoupling of W and Sn mineralisation and distinct styles of mineralisation across the orogen and share similar pattern to that of the Nanling region in China. The proposed model contributes to a deeper understanding of the diversified W-Sn mineralisation in the orogen and provides valuable insights for guiding future prospecting endeavours in both W-only and W-Sn systems.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106662"},"PeriodicalIF":3.2,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924854","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":"Fluid evolution of the Ermi porphyry Cu system, southern Jilin Province, northeastern China","authors":"Guozhen Dong ,&nbsp;Junkang Zhao ,&nbsp;Jinggui Sun ,&nbsp;Jilong Han","doi":"10.1016/j.oregeorev.2025.106664","DOIUrl":"10.1016/j.oregeorev.2025.106664","url":null,"abstract":"<div><div>The Ermi Cu deposit of northeastern China, is a “reduced” porphyry-type Cu deposit associated with emplacement of dioritic to granitic intrusions of Late Cretaceous. Mineralization style at Ermi is characterized by sequenced sulfides, from early pyrrhotite–pyrite to chalcopyrite to late arsenopyrite, which is related to the sericite alteration. These sulfide phases suggest an intermediate to low sulfidation state of Ermi ore system. Their slightly heavier S isotopic compositions, combined with the systematic variation of H and O compositions of hydrothermal fluids, have a vector towards a magmatic origin of mineralizing fluids that were increasingly mixed with meteoric water. A detailed microthermometric study of fluid inclusions hosted in quartz of different fluid stages also indicates a cyclic dilution of meteoric water, with cooling down by 200 ℃ (from 385℃ to 185℃). The cooling of mineralizing fluids in the Ermi porphyry Cu system is considered to have a first-order control on the Cu precipitation by decreasing the solubility of Cu complex in fluids. The Cu mineralization formed at pressure of 205 ± 56 bars under hydrostatic conditions, estimated using temperature and salinity of fluid inclusions of boiling assemblage, corresponding to a depth of emplacement of 2.1 ± 0.6 km beneath the paleowater table.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106664"},"PeriodicalIF":3.2,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144138181","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":"Traces of metasomatic episodes and hydrothermal REE fractionation in the vein filling apatite phases of the Jolotca ore field in the Ditrău Alkaline Massif, Romania","authors":"Krisztián Fintor ,&nbsp;Luca Kiri ,&nbsp;Heléna Walter ,&nbsp;Alexandra Tsay ,&nbsp;Ferenc Kristály ,&nbsp;Elemér Pál-Molnár","doi":"10.1016/j.oregeorev.2025.106646","DOIUrl":"10.1016/j.oregeorev.2025.106646","url":null,"abstract":"<div><div>The Jolotca ore field in the Ditrău Alkaline Massif (Eastern Carpathians, Romania) hosts REE-bearing mineralisation resulting from complex post-magmatic hydrothermal activity and multiple metasomatic overprinting stages. Apatite, a common phosphate mineral in Jolotca, serves as a key indicator of these alterations, with detailed analysis providing insights into the physicochemical conditions of each stage. Jolotca apatites are classified into two main textural groups: groundmass type (G), which forms crystal aggregates in the carbonate gangue, and the less abundant scattered type, which occurs as thin veinlets (SV) or in sheared bands (SS). Cathodoluminescence imaging reveals distinct apatite phases, formed in the following sequence: (1) groundmass apatite: tawny (G_T) → dark orange (G_O) → yellow (G_Y) → green (G_G); (2) scattered apatite in veinlets: violet-blue (SV_V) → yellow (SV_Y); and in sheared bands: greyish-green (SS_G) → yellow (SS_Y). REE content decreases from older to younger apatite generations, with the groundmass apatite showing an increase in MREE + HREE relative to LREEs over time. The G_T phase of the groundmass apatite represents the original phase, while the subsequent ones (G_O, G_Y, G_G) represent stages of metasomatic overprinting. The G_T phase, representing the original apatite, formed from a CO₂-rich (13.3 ± 7.3 mol%), low-salinity (14 ± 8 mass% NaCl_eq.) H₂O-NaCl-CO₂ fluid under 120–250 MPa pressure and 320–380 °C. Subsequent metasomatic stages involved fluids with reduced CO₂ content (2 ± 1 mol%), higher salinity (15.3 ± 8 to 25.8 ± 2 mass% NaCl_eq.), and elevated Ca/Na ratios (<em>X</em>_NaCl: 0.45 to 0.96) at pressures of 140–385 MPa and temperatures of 350–420 °C. Changes in the distribution of rare earth elements (REE) likely resulted from temperature-dependent fractionation, leading to a relative MREE + HREE enrichment in apatite during the crystallization sequence.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"183 ","pages":"Article 106646"},"PeriodicalIF":3.2,"publicationDate":"2025-05-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143947217","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":"Joint extraction method for entity relations from mineral resources reports integrating dependency parsing and improved graph convolutional networks","authors":"Qinjun Qiu ,&nbsp;Xiangguo Jin ,&nbsp;Miao Tian ,&nbsp;Qirui Wu ,&nbsp;Liufeng Tao ,&nbsp;Jianguo Chen ,&nbsp;Zhong Xie","doi":"10.1016/j.oregeorev.2025.106640","DOIUrl":"10.1016/j.oregeorev.2025.106640","url":null,"abstract":"<div><div>Geological reports, as crucial technical documents reflecting the outcomes of geological survey work, encapsulate extensive expert and domain knowledge. Geological knowledge graphs integrate vast amounts of data, facilitating efficient and rapid extraction of knowledge embedded within geoscientific data. The extraction of geological entity relations is a key method in creating these knowledge graphs. Existing techniques for extracting geological entities and their relations encounter difficulties such entity overlap, relation overlap, and the challenge of obtaining deep semantic information because of the vastness and complexity of geological data. Our study suggests a collaborative extraction model for entity relations that integrates dependency syntactic relations with a graph convolutional network (GCN) in order to address these problems. This model learns dependency syntactic structures and deep semantic information by building a GCN that includes dependency syntactic relations. A pointer network decoder is then added to increase entity relation extraction efficiency. Dependencies between words in a phrase, such as subject-verb and verb-object relations, are revealed via dependency syntactic analysis. By structuring these dependencies into a graph, the model captures syntactic structural information. Through operations involving adjacency matrices and feature matrices, the model effectively propagates and aggregates node information, thereby capturing the global dependency syntactic structure and deep semantic information of sentences. The integration of dependency syntactic relations with GCN processing enables the model to more accurately comprehend entity relations within sentences. Results from experiments show that this model successfully tackles problems like overlapping entity relations and the challenge of gleaning deep semantic information from geological texts. It achieves a 79.73% accuracy rate and a 77.98% F1 score on geological text datasets.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106640"},"PeriodicalIF":3.2,"publicationDate":"2025-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898611","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":"Trace element geochemistry in apatite from the Gabo pegmatite type lithium deposit, Tethyan Himalaya, China: Implications for petrogenesis and metallogenesis","authors":"Jiangang Fu ,&nbsp;Guangming Li ,&nbsp;Weikang Guo ,&nbsp;Linkui Zhang ,&nbsp;Suiliang Dong ,&nbsp;Yingxu Li ,&nbsp;Lei Dong ,&nbsp;Yanjie Jiao","doi":"10.1016/j.oregeorev.2025.106645","DOIUrl":"10.1016/j.oregeorev.2025.106645","url":null,"abstract":"<div><div>The Gabo pegmatite-type lithium deposit is located at the northeastern end of the Kulagangri dome in the eastern segment of the Himalayan metallogenic belt in Xizang and represents a recently discovered rare metal deposit. The ore-bearing pegmatites are primarily hosted within the marble of the Kulagangri dome detachment system, with lithium as the main ore-forming element, accompanied by rare metals such as beryllium, niobium, and tantalum. This study conducted detailed mineral geochemical research on apatite from the spodumene pegmatite and tourmaline granite in the Gabo mining area. The analytical results reveal that the apatite in the spodumene pegmatite of the Gabo lithium deposit exhibits high rare earth element (REE) contents. The total REE content in apatite from coarse-grained spodumene pegmatite ranges from 3085 to 9297 ppm, with TE_1,3 values of 1.4–1.6, Eu* values of 0.001–0.006, and Sr contents of 4.9–15.83 ppm. In fine-grained spodumene pegmatite, the total REE content ranges from 3899 to 7680 ppm, with TE_1,3 values of 1.4–1.5, Eu* values of 0.002–0.006, and Sr contents of 7.22–34.06 ppm. The apatite in spodumene pegmatite also shows low Zr/Hf and Nb/Ta ratios but high Y/Ho ratios (&gt;28). In contrast, the tourmaline granite has a total REE content ranging from 848 to 3285 ppm, TE_1,3 values of 1.1–1.2, Eu* values of 0.041–0.214, and Sr contents of 38.75–72.14 ppm. These results indicate that the apatite in both the tourmaline granite and spodumene pegmatite of the Gabo lithium deposit exhibits high ∑REE, low Sr, a pronounced M−type tetrad effect, high TE_1,3 values, and significant negative Eu anomalies, reflecting highly fractionated characteristics. The spodumene pegmatite, in particular, shows ultra-high fractionation. These features suggest that the mineralization of the Gabo lithium deposit occurred during the magmatic-hydrothermal transition stage, where extensive fluid exsolution from the melt led to the significant enrichment and mineralization of lithium and other rare metal elements. Based on these findings, four mineralogical indicators of apatite in pegmatite—∑REE &gt; 2500 ppm, high tetrad effect (TE_1,3 &gt; 1.3), extremely low Eu* (&lt;0.01), and low Sr (&lt;35 ppm)—provide theoretical guidance for future exploration of new pegmatite-type lithium and other rare metal deposits in the Himalayan metallogenic belt.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106645"},"PeriodicalIF":3.2,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143946943","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":"Petrogenesis of Early Cretaceous Duorenlieqian igneous rocks (113 ∼ 117 Ma) in the western Bangong-Nujiang metallogenic belt, Tibet, China: Implications for tectono-magmatic evolution and porphyry Cu-Au mineralization","authors":"Hao Sun ,&nbsp;Yang Song ,&nbsp;Jamie J. Wilkinson ,&nbsp;Zhibo Liu ,&nbsp;Ming Zheng ,&nbsp;Beiqi Wang","doi":"10.1016/j.oregeorev.2025.106650","DOIUrl":"10.1016/j.oregeorev.2025.106650","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Porphyry copper deposits are classic products of arc magmatic activity at convergent plate boundaries. Understanding the signatures of arc magmas is essential for reconstructing the dynamic evolution of plate boundaries and predicting copper resource potential. The southern Qiangtang subterrane in the Bangong-Nujiang metallogenic belt hosts several subduction-related porphyry and epithermal copper-gold deposits. However, such deposits are quite scarce in the northern Lhasa subterrane, where the potential for subduction-related porphyry copper mineralization remains poorly understood. Here we present zircon U-Pb geochronology, trace elements, Hf isotopes, and whole-rock geochemical compositions for newly discovered mafic to felsic igneous rocks in the Duorenlieqian area, northern Lhasa subterrane. The zircon U-Pb geochronology results show that the hornblende gabbro, diorite porphyry and quartz diorite formed at 114.4 ± 0.9 Ma, 116.8 ± 1.5 Ma, and 113.4 ± 1.7 Ma, respectively. The hornblende gabbro and diorite porphyry exhibit arc magmatic geochemical affinities with low SiO&lt;sub&gt;2&lt;/sub&gt; contents (48.4–53.0 wt% and 52.3–56.4 wt%, respectively), high Mg&lt;sup&gt;#&lt;/sup&gt; values (49–51 and 46–50, respectively), depleted whole-rock Sr-Nd isotopic compositions [(&lt;sup&gt;87&lt;/sup&gt;Sr/&lt;sup&gt;86&lt;/sup&gt;Sr)&lt;sub&gt;i&lt;/sub&gt; = 0.7040 to 0.7043, 0.7053 to 0.7055, respectively; ε&lt;sub&gt;Nd&lt;/sub&gt;(t) = +4.20 to + 5.96, +2.72 to + 5.06, respectively] and zircon Hf isotopic compositions [ε&lt;sub&gt;Hf&lt;/sub&gt;(t) = +11.8 to + 15.4, +9.1 to + 11.3, respectively]. Additionally, they have high Th/Ce and Th/Nb ratios, as well as variations in Nb/Zr ratios. These characteristics suggest that they were likely derived from mantle wedge metasomatized by hydrous sediment melts. The quartz diorite, sharing arc magmatic affinities but relatively more enriched whole-rock Nd isotopic compositions (+2.09 to + 3.48) and lower Mg&lt;sup&gt;#&lt;/sup&gt; (34–48) values compared to the gabbro and diorite porphyry, is interpreted to be derived from partial melting of juvenile lower crust with minor mantle input. Based on our new data, integrated with recent studies, we propose that during the same geological period (113 ∼ 117 Ma), the Bangong-Nujiang Ocean basin exhibited a diachronous geodynamic background from east to west, characterized respectively by lithospheric delamination, slab break-off and slab roll-back. This provides new evidence for the diachronous closure of the Bangong-Nujiang Ocean from east to west during the Cretaceous. The diorite porphyry and quartz diorite have similarly high zircon Eu&lt;sub&gt;N&lt;/sub&gt;/Eu&lt;sub&gt;N&lt;/sub&gt;* ratios (averaging 0.62 and 0.56, respectively) that are comparable to those of fertile igneous rocks formed in comparable tectonic settings, but they contain notably higher zircon Ti contents (averaging 15.5 ppm and 9.5 ppm, respectively). This suggests that although these magmas are relatively water-rich, they have not yet reached the super-wet conditions that are fundamental to por","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106650"},"PeriodicalIF":3.2,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143904109","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":"Copper and gold metallogeny in West China: An overview","authors":"Huawei Li ,&nbsp;Zhiming Yang","doi":"10.1016/j.oregeorev.2025.106644","DOIUrl":"10.1016/j.oregeorev.2025.106644","url":null,"abstract":"<div><div>West China, straddling the Tethyan and Central Asian metallogenic domains, is a significant region for copper and gold resources. To better understand these deposits’ spatial-temporal distribution, Cu-Au resource characteristics, and metallogenic features in different metallogenic domains, we conducted a data compilation on key information from 267 Cu-Au deposits in four metallogenic domains (the Central Asian, Proto-Tethys, Paleo-Tethys, and Neo-Tethys) of West China. Based on our comprehensive database, major characteristics of copper and gold mineralization in West China include: diverse deposit types, dominant Cu-Au resource contribution of porphyry and orogenic deposits, post-subduction dominance, and the Neo-Tethys importance. This overview enhances our understanding of copper and gold resources in Western China, offering a foundational reference for comparative studies and guiding future resource exploration efforts.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106644"},"PeriodicalIF":3.2,"publicationDate":"2025-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143898612","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":"Petrogenesis and evolution of internally zoned pegmatites: A tourmaline perspective from the Dakalasu deposit, Chinese Altai","authors":"Yong-Qi Xia ,&nbsp;Ming-Jie Tuo ,&nbsp;Nuo Li ,&nbsp;Nuerkanati Madayipu ,&nbsp;Chao Zhang ,&nbsp;Li-Ning Cheng ,&nbsp;Wen-Bo Wang ,&nbsp;Dong-Mei Qi","doi":"10.1016/j.oregeorev.2025.106624","DOIUrl":"10.1016/j.oregeorev.2025.106624","url":null,"abstract":"<div><div>The role of fractional crystallization and partial melting on pegmatite is controversial. To constrain the evolution and petrogenesis of internally zoned pegmatites, we selected the Dakalasu No. 1 pegmatite dike, Chinese Altai, as a case, and used tourmaline as a probe. Tourmalines were developed along the boundary between pegmatite and the host biotite granite porphyry (Tur B_Ⅰ), at the border zone Ⅱ (Tur B_Ⅱ) and further at the intermediate zone (Tur IM), but absent in the central zone of the pegmatite. All the tourmalines belong to alkaline schorl series. Tur B_Ⅰ exhibits elevated concentrations of Mg (3.42–4.63 %) and V (104.2–263.4 ppm), coupled with low Al content at Y site, indicative of interaction between pegmatite and the host biotite granite. Tur B_Ⅱ and Tur IM have high ratios of Fe/Mg (5.00–6.70), but low Mg/(Mg + Fe) (0.13–0.18), suggestive of a magmatic origin. The contents of rare metals (Li, Be, Nb, Ta, and Sn) of tourmaline increase inward, whereas the contents of Mg, Ca, Sr, Ni, V, Cr and the ratio of Mg/(Mg + Fe) decrease, suggesting a sequential evolution from the border to the intermediate zone. All tourmalines contain low content of Li, indicating a limited fractional crystallization. Boron isotopes (δ¹¹B = −15.84 ‰ – −14.55 ‰) in tourmaline indicate that the pegmatite dike originates from the low-degree partial melting of metasedimentary rocks, rather than fractional differentiation of the host granite. We propose that tourmaline in zoned pegmatites can be employed as a pathfinder to explore the petrogenesis and evolution of pegmatite.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"181 ","pages":"Article 106624"},"PeriodicalIF":3.2,"publicationDate":"2025-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143882996","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":"Zircon trace elemental and Hf-O isotopic constraints on the petrogenesis of the REE-fertile and barren alkaline rocks in the South Qinling Belt, China","authors":"Zhihui Zha ,&nbsp;Wei Zhang ,&nbsp;Ronglin Ma ,&nbsp;Youwei Chen ,&nbsp;Wei Terry Chen","doi":"10.1016/j.oregeorev.2025.106641","DOIUrl":"10.1016/j.oregeorev.2025.106641","url":null,"abstract":"<div><div>Alkaline silicate rocks and/or associated carbonatites are important hosts of rare earth elements (REE) resources. Previous studies have suggested that REE-fertile alkaline rocks and/or carbonatites were derived from a mantle source that may have once been metasomatized by recycled crustal materials. However, it is still not clear if the source metasomatism is a prerequisite of REE mineralization. In this study, we investigated and compared both REE-fertile and barren alkaline plutons in South Qinling, Central China with emphasis on zircon elemental and Hf-O isotopic compositions. The REE-fertile alkaline pluton, i.e. the Miaoya (MY) complex, is dominated by syenite with minor coeval carbonatite dykes/stocks, whereas the REE-barren alkaline plutons, i.e. the Huangyangshan (HYS) and Guanzishan (GZS) plutons, are composed mainly of quartz-bearing syenite without carbonatites. Our new U-Pb dating of magmatic zircon demonstrates that the fertile and barren alkaline complexes have identical ages of ca. 440 Ma. The syenites in both fertile and barren alkaline plutons have similar affinities of A-type granitoids with comparably high Ti-in-zircon temperatures of 632 to 878 °C. In particular, the fertile syenites have zircon Hf and O isotopic compositions (ε_Hf(t): −3.4 to + 8.2, δ¹⁸O: +3.3 to + 6.9 ‰) also broadly similar to the barren syenites (ε_Hf(t): −1.6 to + 10.1, δ¹⁸O: +3.5 to + 8.0 ‰), indicating that they may be sourced from a common, enriched mantle source that likely included components from oceanic crustal material, such as sediments and/or altered oceanic crust. However, compared to the fertile syenites, the barren syenites exhibit much higher SiO₂ (up to 75 %) but lower MgO contents, and thus were suggested to be likely formed through partial melting of a juvenile mafic lower crust. It is reasonable to speculate that the mafic lower crust was likely formed from mafic magmas derived from the enriched mantle due to their undistinguishable zircon Hf and O isotopic ratios. Zircon trace element analyses reveal that the barren syenites exhibit ΔFMQ values (+0.95 to + 6.74) obviously higher than those of the fertile syenites (−1.14 to + 0.88), indicating a more oxidized source characteristic. Since an oxidized source is conducive to carbon stability, promoting the formation of carbonatite-bearing syenite complexes (which are favorable for REE mineralization), the absence of carbonatites in the relatively oxidized Huangyangshan and Guanzishan syenites might be attributed to a lack of carbon in their source. Our findings emphasize the critical role of oceanic crust recycling in producing REE-fertile, carbonaceous silicate melts and underscore that source variations exert a primary control on REE fertility of alkaline plutons within specific alkaline magmatic belts.</div></div>","PeriodicalId":19644,"journal":{"name":"Ore Geology Reviews","volume":"182 ","pages":"Article 106641"},"PeriodicalIF":3.2,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143907023","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}