Table of Content

20 June 2026, Volume 32 Issue 03

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Granite Petrogenesis and Continental Crust Growth

ZHENG Yongfei, ZHAO Zifu, ZHANG Shaobing, GAO Peng

2026, 32(03):  257-278.  DOI: 10.16108/j.issn1006-7493.2026054

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Granite is a unique rock type on Earth, whose petrogenesis is inseparably linked to the formation and evolution of
continental crust. However, intense debates have long existed within the geological community regarding the mechanisms of granite formation, the modes of continental crust growth, and the intrinsic connections between these processes. On the basis of the geochemical evolution of crust-mantle systems, this paper presents a systematic review on frontier advancements, core controversies, and future directions in studies of granite genesis and continental crust growth. The main content encompasses two end-member paradigms for granite petrogenesis (mantle differentiation vs. crustal anatexis), the spatiotemporal evolution of crustal growth rates, complexities of magmatism in collisional orogens, potentials and limitations of zircon isotope tracing, as well as critical reflections on methodological approaches. A holistic analysis reveals a complex dialectical relationship between granite petrogenesis and continental crust growth: granites can serve as the direct record of crustal growth (mantle-derived
magma differentiation) or the product of crustal reworking (crustal anatexis). These two mechanisms carry fundamentally different implications for formation and evolution of the continental crust but are often indistinguishable based merely on either elemental ratios or isotopic ratios alone. Future research requires clarifying core concepts, developing integrated geochemical proxies, prioritizing process-oriented investigations, embracing uncertainties, and transcending paradigmatic boundaries. 


Petrogenesis and Metallogeny of the Rare-metal Granite and Pegmatite

WU Fuyuan

2026, 32(03):  279-311.  DOI: 10.16108/j.issn1006-7493.2026047

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Rare-metals are refered to elements with crustal abundances less than 100×10-6, or those that are difficult to be extracted and refineed in industry. Presently, rare-metal elements include lithium (Li), beryllium (Be), rubidium (Rb), cesium (Cs), niobium (Nb), tantalum (Ta), zirconium (Zr) and hafnium (Hf), and sometimes tungsten (W), tin (Sn), and rare earth elements (REEs). Rare-metal elements are mostly incompatible in geochemistry, and hence are concentrated in granites or pegmatites. The ongoing global transformation of green economy has created enormous demand for rare metals, which makes the granites and pegmatites critical subjects for current geological studies. In perspective of petrology, rare-metal granites and rare-metal pegmatites are kinds of rock that the rare-metal minerals exist as major or minor components, and then can be used for rock naming and classification, such as tourmaline granite, columbite granite, lepidolite granite, spodumene pegmatite, and pollucite pegmatite. It is generally accepted that the rare-metal granites come from the highly fractionation of granitic magmas, but it is much debated regarding formation of the rare-metal pegmatites. It is concluded in this paper that rare-metal pegmatites are similarly products of highly fractionation of granitic magmas, and there is currently no evidence for an independent origination of rare-metal pegmatitic magma derived from partial melting of rare-metal enriched source rocks. The different occurrences of rare-metal granites or rare-metal pegmatites are depend on their volatile components. The fluorine-rich granitic magmas tend to form rare-metal granites, and boronbearing granitic magmas mostly evolve into pegmatites, respectively, after a high degree of fractional crystallization. Therefore, whatever rare-metal granites or rare-metal pegmatites, they are products of granitic magmas after a highly degree of differentiation. Currently, the rare-metal granite and pegmatites can be divided into peraluminous and peralkaline type, but they cannot be simply classified into I- or A-type granites, since the highly fractionation makes it difficult to determine their petrogenetic types. Considering that the Nanling Mountain in southern China is the largest distribution area of rare-metal granites in the world, and China holds a significant portion of rare-metal pegmatites in the world, the future research for the Chinese scientists should focus on the dissolution capacity of rare-metals in granitic magmas under different kinds of volatile, such as fluorine, boron, lithium, phosphorus. Meanwhile, the mechanisms and conditions for a high degree of magmatic differentiation of granitic magmas should be carefully exminated. Realizing these works, a new breakthrough for the study of rare-metal granites and pegmatites in China is expected.

Classification Principles and Schemes for Superimposed Basins

YANG Shufeng, CHEN Hanlin, JIA Dong, LI Yong, LIN Xiubin, HUANG Shaoying, CHENG Xiaogan, WEI Hongxin, WU Lei, ZHANG Fengqi, CHEN Long

2026, 32(03):  312-319.  DOI: 10.16108/j.issn1006-7493.2026075

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Basin classification has always been an important aspect of basin tectonic studies. However, most classical basin
classification schemes focus on prototype basins and emphasize the close relationship between single-cycle basin and hydrocarbon accumulation. But, the majority of basins have undergone multi-stage tectonic evolution, thereby developing into superimposed basins. Therefore, it is necessary to develop a classification system for superimposed basins. The classification of superimposed basins should fully reflect their multi-cycle tectonic evolution and the inheritance and transformation of structures, integrating petroleum geological characteristics so as to directly and effectively serve oil and gas exploration in hydrocarbon-bearing basins, as well as the comparison and evaluation between basins. Based on a review of classical basin classification schemes, this paper proposes principles and a classification scheme for superimposed basins. In classifying superimposed basins, in addition to considering the prototype basin type determined by the tectonic setting at a particular stage of basin evolution, it is essential to focus on the transformation and inheritance of structural characteristics between two phases of basin formation. Based on these principles, superimposed basins are classified into four types: positive inversion basins, negative inversion basins, inherited rift basins, and inherited foreland basins. On this basis, the global distribution of superimposed basins and their implications for hydrocarbon resources are analyzed. 

Water in Granites：Tracing Method and Its Application

XU Yigang, YANG Chuanmao, XIA Xiaoping, YANG Jinhui, ZHANG Wanfeng, YANG Qing, CUI Zexian

2026, 32(03):  320-333.  DOI: 10.16108/j.issn1006-7493.2025066

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Granitic rocks are the primary components of the continental crust and are crucial for understanding continental evolution and the enrichment mechanisms of critical metals. Water, as the most critical factor in granite formation, plays vital roles in the entire lifetime of granitic magmatic systems. Therefore, accurately determining the water content in granitic magmas and tracing its sources are of great significance for understanding granite petrogenesis. Over the past two decades, advances in insitu U-Pb-Hf-O isotope analysis of zircon have revolutionized our understanding of granite formation. However, the role of water in granite genesis remains poorly constrained, if any, on the qualitative basis. This paper, based on a review of recent studies on water in zircon, integrates U-Pb-Hf-O isotope analysis of zircon with hydrogen isotope analysis of apatite to establish a tracing system for the content and sources of water in granite. Using Late Mesozoic granites from the North China Craton as an example, we demonstrate the application potential of this methodological framework and discuss future research directions in this field. 

Exploration, Pioneering and Innovation for the Genesis of Granitic Volcanic Plutonic Complexes

XU Xisheng, HE Zhenyu, XIA Yan

2026, 32(03):  334-338.  DOI: 10.16108/j.issn1006-7493.2026053

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The granitic volcanic-plutonic complexes in southeastern China constitute a natural laboratory for investigating the
genetic links between volcanic and plutonic rocks, crust-mantle interaction, tectonic geodynamic settings, and crystal-melt separation. Over the past half century, Academician Dezi Wang and Professor Xinmin Zhou led a research team in carrying out systematic studies, through which they proposed the concept of granitic volcanic-plutonic complexes. Using subvolcanic granites as the key link, they examined their genesis and distribution patterns in terms of temporal, space, and source affinities, and established a set of geological and geochemical discriminant criteria. On the basis of integrated studies of petrology, tectonics, sedimentary basins, and geophysics, they proposed a tectono-magmatic model attributing the origin of the granitic volcanicplutonic complexes in southeastern China to the combined effects of oceanic slab subduction, basaltic magma underplating, and partial melting of the middle to lower crust. In terms of detailed magmatic crystallization processes, they identified and revealed a series of key evidences for magma recharge, crystal accumulation, mush rejuvenation, and melt extraction, thereby further elucidating the magmatic evolution of granitic volcanic-plutonic complexes, as well as their relationship to the vertical compositional differentiation of the continental crust. 

Why Do Granitic Magma Systems Commonly Fail to Erupt? Transcrustal Magma-Dynamic Mechanisms of Intrusive-Volcanic Asymmetry

MA Changqian, HUANG Guizhi

2026, 32(03):  339-353.  DOI: 10.16108/j.issn1006-7493.2025063

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Granitic magma systems commonly exhibit a pronounced asymmetry between deep crustal emplacement and solidification (intrusion) and surface eruption (volcanism), with intrusive products greatly exceeding erupted products. Building upon Dezi Wang’s concept of a unified volcanic-intrusive magmatic system, this study introduces the framework of transcrustal magma plumbing systems and the dynamic crystal mush paradigm to explore the deep dynamic mechanisms responsible for the frequent failure of granitic magmas to erupt. The analysis is conducted from the perspectives of system behavior, transportpathway topology, and time-scale coupling. The results show that: (1) granitic magma systems fundamentally operate as dynamic crystal mush systems characterized by long-term cold storage and intermittent magma transport. As crystal contents progressively increase and exceed the ~60% rigid percolation threshold, the system enters a rheologically locked state marked by high viscosity and low permeability, resulting in a drastic decline in the long-distance transport capacity of melt and promoting progressive in situ solidification; (2) the crust acts as a triple “dynamic filter” composed of tectonic, gravitational, and thermal barriers that progressively screen ascending magmas. Neutral buoyancy levels, episodic opening of tectonic pathways, and rapid thermal dissipation collectively hinder the establishment of sustained transcrustal transport channels, causing most magma pulses to be trapped and frozen within the crust before reaching the surface; (3) granitic systems exhibit a pronounced mismatch of time scales. Chemical differentiation and isotopic homogenization generally occur over 105-106-year time scales, whereas the transient events capable of triggering pathway connection and eruption commonly last only years to centuries. Consequently, granitic systems display a characteristic behavior of “continuous chemical evolution but discontinuous dynamic transport”; (4) volatile behavior exerts dual dynamic effects. Early-stage volatile enrichment and exsolution may temporarily reduce melt viscosity and generate overpressure, thereby facilitating transient local pathway connection, whereas late-stage degassing promotes melt stiffening, rapid crystallization, and hydrothermal self-sealing, driving the system back into a rheologically locked state; and (5) during longterm incremental assembly, granitic magma systems exhibit a pulsed behavioral pattern characterized by “closed backgroundtransient connection-renewed closure.” Large granitic plutons essentially represent the cumulative products of repeated failed transient connection events, whereas eruptions constitute only rare peak events formed when the system temporarily departs from its stable state. This study emphasizes that the paradigm shift from the traditional static “large magma chamber” model to a dynamic “transcrustal crystal mush system” framework provides a unified magmatic-dynamic explanation for the widespread intrusive-dominated nature of granitic systems, and offers a new transcrustal system-dynamics framework for understanding longterm continental crustal evolution, thermal restructuring, and related mineralization processes. 

Crust-Mantle Magmatism in the Jiangxi to Anhui Segment of the Yangtze River and Its Constraints on Regional Metallogeny

DU Yangsong, CAO Yi, QIN Xinlong, PANG Zhenshan

2026, 32(03):  354-370.  DOI: 10.16108/j.issn1006-7493.2026078

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Numerous Mesozoic meso-epizonal small intrusions, hosting various rock enclaves, are widely distributed in the Jiangxi to Anhui segment of the Yangtze River. Some mineral peritectics occur in both the intrusions and their enclaves, while exsolved phases from melt inclusions are present in various mineral grains of these rocks. Based on comprehensive field investigations and detailed petrographic observations, the intrusions in the study area are classified into eight groups: those associated with postcollisional gold, gold-copper and copper deposits, those related to post-orogenic gold deposits, dispersed element mineralization, copper and iron deposits, and barren intrusions. The rock enclaves within the intrusions are divided into five types: hybrid rocks, mantle-derived xenoliths, cumulates, polycrystalline aggregates, and metamorphic xenoliths. The peritectic minerals in the intrusions and their enclaves are categorized into four types: mantle-derived crystals, megacrysts, cumulus crystals, and polycrystals. The exsolved phases from melt inclusions in various minerals of the intrusions and enclaves are grouped into two categories: oxides and sulfides. Systematic mineralogical and geochemical investigations were conducted on the intrusions, their rock enclaves, and various minerals within them. The results demonstrate that two major episodes of crust-mantle magmatism occurred in the Jiangxi to Anhui segment of the Yangtze River: the Proterozoic and Mesozoic episodes. The Proterozoic crustmantle magmatism was dominated by mantle-derived magma underplating and crust-mantle hybrid magmatism, followed by regional metamorphism. In contrast, the Mesozoic crust-mantle magmatism comprised three distinct phases of mantle-derived magma underplating and crust-mantle hybrid magmatism. These two episodes of crust-mantle magmatism triggered a series of post-collisional to post-orogenic magmatic events, driving the corresponding crust-mantle magma evolution. This evolution is primarily recorded in the variations of intrusion-enclave assemblages, formation ages, physicochemical conditions, mineral associations, and geochemical compositions. With respect to metallogenic effects, the crust-mantle magmatism in the study area exerts a fundamental control on both regional mineralization processes and metallogenic regularity. The regional mineralization processes are governed by four key factors: sources of ore-forming materials, mechanisms of metal acquisition and enrichment, fluid/melt transport pathways and driving forces, and post-mineralization preservation environments and conditions. The regional metallogenic regularity is mainly characterized by the temporal-spatial distribution of ore deposits and the genetic superposition of multiple mineralization events. 

Composite Ore-controlling of Basement Tectonics and Volcanic Structure in the Wuyishan Metallogenic Belt—A Case  Study of the Dehua-Youxi-Yongtai concentration area in Fujian Province

XING Guangfu, FAN Feipeng, DUAN Zheng, XIAO Fan, ZHAO Xilin, HONG Wentao, ZHOU Yan

2026, 32(03):  371-387.  DOI: 10.16108/j.issn1006-7493.2026072

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The Wuyishan metallogenic belt exists widespread Mesozoic epithermal-porphyry gold-copper metallogenic system, where mineralization closely related to ancient basement and volcanism. The composite ore-controlling of basement tectonics and volcanic structure is not enough understood. This paper reviews recent advances on Neoproterozoic-early Paleozoic basement rocks and their tectonic attributes, as well as Mesozoic volcanism-metallogeny in the Wuyishan metallogenic belt, and then focuses on the basement and caldera of the Dexi-Yixi-Yongtai ore concentration area in central Fujian Province. The results show that multi-stage Au-Cu mineralizations in the study area were jointly controlled by basement and volcanic structures. The basement is dominated by Neoproterozoic accretionary complexes and Early Paleozoic intrusions, which made up large composite thrust-gliding nappe system in mid-late Jurassic (170-168 Ma). The Leitan caldera is identified as the most completely preserved mid-late Jurassic caldera in South China, and spatially outward, its diagenesis and mineralization become younger from middle to late Jurassic, with epithermal Au- Cu deposits transitioning from intermediate- to low- sulfidation. This study can provide valuable insights for tectonic evolution and ore prospecting in volcanic areas of the belt.

Research Progress and Major Exploration Breakthroughs on Alaskite-type Uranium Deposits in Namibia

FAN Honghai, CHEN Xu, HE Debao, CHEN Jinyong, CHEN Donghuan, WANG Shengyun, GU Dazhao

2026, 32(03):  388-404.  DOI: 10.16108/j.issn1006-7493.2025062

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The Southern Central Zone of the Damara Orogen in Namibia is one of the world’s most important alaskite-type uranium ore clusters, hosting super-large uranium deposits such as Rössing and Husab. Major exploration breakthroughs have been achieved in this region in recent years. This paper systematically reviews the regional geological setting and geological characteristics of alaskite-type uranium deposits, and takes the “source-transport-trap-modification-preservation” metallogenic process as the main framework to analyze key aspects including ore-forming material sources, magmatic origin and evolution, tectonic-magmatic coupling mineralization, and post-ore modification. The results show that alaskites can be classified into six types (A-F), of which only D- and E-types are mineralized. Barren alaskites originated from muscovite dehydration melting during the syn-collisional stage, whereas mineralized alaskites originated from biotite dehydration melting during the latecollisional stage. Biotite melting introduced F^- into the magma, forming UF_m ^4-m complexes that enabled uranium transport in the  melt, representing the key mechanism for the formation of ore-forming magma. During fractional crystallization, biotite separation removed Nb from the residual melt, serving as an important factor in controlling uraninite-type versus betafite-type mineralization. The D4 tectonic regime transformation triggered uranium mineralization. The Khan River Lineament as the conduit, dome margins and marble contacts as the emplacement sites of alaskite bodies, together with Mesozoic hydrothermal superimposition and Cenozoic supergene leaching, constitute a complete mineralization-modification-preservation process. The comprehensive information prediction method based on metallogenic theory delineated 14 prospective targets within the Rössing mining license, with a predicted resource potential of approximately 140,000 tons of uranium. The A1 (Z17-19) target has been confirmed through drilling as a very large uranium deposit, achieving a major exploration breakthrough. 

Study on Metallogenic Regularity and Construction of Prospecting Model for Granite-Mica Type Lithium Deposits in Jiangxi Province

LOU Fasheng, GONG Min, ZHANG Fushen, NIE Xiaoliang, CHEN Jun, XU Zhe, LIU Shuang, WANG Huimin, XIONG Yanyun

2026, 32(03):  405-415.  DOI: 10.16108/j.issn1006-7493.2026068

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Lithium, as a crucial strategic mineral, serves as the core resource for China’s new energy industry in realizing the“ Dual Carbon” goals. Currently, China exhibits a high external dependence on lithium resources, making it imperative to expand lithium reserves and enhance the self-sufficiency rate. The granite-mica type lithium deposits in Jiangxi Province are characterized by large scale, low grade, shallow burial depth, and easy exploitation, which have become an important source of lithium resources in China. The rapid prospecting breakthrough and rational development and utilization of this type of lithium deposit will not only effectively reduce China’s external dependence on lithium resources but also exert profound strategic and political significance for the sustainable and high-quality development of China’s new energy industry. In this work, the granite-mica type lithium deposits in the Ganfang ore concentration area, situated on the southern margin of the Jiuling Mountains within the Yichun region of Jiangxi Province, were selected as the research focus. Through systematic investigations into the metallogenic geological setting, magmatic-rock forming and mineralization processes, as well as the temporal and spatial distribution characteristics of the granite-mica type lithium deposits, the metallogenic regularity was comprehensively summarized, and a prospecting model specific to this type of lithium deposit was constructed. This research is intended to provide theoretical foundation and key exploration methodologies for the rapid delineation of prospecting targets of granite-type lithium deposits, thereby facilitating the achievement of major breakthroughs in lithium prospecting.

Mantle Characteristics and the Genesis of Basalts in the Lamont Seamount, the Western Pacific

LAI Zhiqing, ZHAO Guangtao, HAN Zongzhu, YU Hang, JING Bohao

2026, 32(03):  416-426.  DOI: 10.16108/j.issn1006-7493.2026058

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In this study, we report new major and trace element, Sr-Nd-Pb-Hf isotopic compositions for ten basaltic lavas from the poorly studied Lamont seamount in the western Pacific Ocean. The results show that the rock types of the Lamont Seamount are basalt, trachybasalt, alkali basalt and picrite basalt, which belong to silica-undersaturated alkaline rocks. The lavas are generally enriched in LILE and HFSE, depleted in HREE, Zr, Hf and Ti, and show a positive Nb-Ta anomaly. Around 80 Ma, the Lamont Seamount formed the initial shape that mainly was influenced by the Arago hotspot, and then underwent vertical uplift and subsidence movements to change into the current morphology. The magmatic material of the seamount mainly originated from the DM and FOZO mantle, and was also influenced by the HIMU and EMI mantle end-member components. The mantle lithology of the source area is mainly pyroxenite. The basaltic magma mainly originated from the melts of secondary plume emanating from the Pacific Large Low Shear Velocity Province (LLSVP), and multiple batches of magma were stored in the upper mantle magma chamber, and experienced significant crystallization processes of Fe-Ti oxides, amphibole, olivine and plagioclase. Different volcanic rocks underwent different degrees of magmatic fractional crystallization. 

Genesis of the Yajishan Granite Mass on the Northern Margin of Jiuling: Constraints from Chronology, Geochemistry, and Hf Isotopes

ZHANG Fangrong, ZHOU Yu, XU Zhe

2026, 32(03):  427-449.  DOI: 10.16108/j.issn1006-7493.2026067

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Jiuling composite batholith records the Neoproterozoic plate convergence and collision orogeny event in South China. This paper conducts geochemical studies, LA-ICP-MS zircon and monazite U-Pb dating, and zircon Hf isotope analysis on the Yajishan pluton in its northern part. The Yajishan pluton consists of middle- to fine-grained two-mica monzogranite and fine grained muscovite monzogranite, formed at 828 to 817 Ma and 821 to 811 Ma, respectively, belonging to the high-K calc-alkaline granite peraluminous series. The Cr, Co, and Ni contents of the Yajishan pluton are much lower than those of the upper crust, with an A/CNK value greater than 1.1, high Rb/Sr and Rb/Nb values, low Nb/Ta, Zr/Hf, total rare earth element (REE) content, LREE/HREE ratio, and strong Eu negative anomalies. Its positive zircons εHf(t) values (+3.2~+6.4; -0.6~+3.7) are consistent with the surrounding Shuangqiaoshan Group strata (-17.7~+15.8), accompanied by lower CaO/Na2O ratio and Mg# value. The study suggests that the Yajishan pluton was formed through partial melting of the Shuangqiaoshan Group after large-scale tectonic napping and crustal thickening caused by the collision between the Cathaysian and Yangtze blocks. The Neoproterozoic granitic magma in the Jiuling area from its early to mid-to-late stages roughly underwent three stages, from the first stage (Jiuling and Meiling pluton) and the second stage (Shihuajian, Jiuxiantang and Xiyaowu pluton)of tonalite- biotite granodiorites-biotite granite to the third stage (Yajishan pluton) of two-mica monzogranite-muscovite monzogranite, reflecting the tectono-magmatic evolution law of multiple magma pulses creating a composite batholith.

Curriculum Cluster Reconstruction and Digital Intelligence Empowerment in Earth Material Science

MA Qiang, MA Changqian, ZHAO Shanrong, SHE Zhenbing, WANG Guoqing, WANG Lianxun, CHEN Ming

2026, 32(03):  450-456.  DOI: 10.16108/j.issn1006-7493.2026055

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The Earth Material Science course cluster is a foundational component of geology and related disciplines, and its systematic reform is crucial for enhancing geoscience talent training and addressing evolving disciplinary and national strategic needs. Using the course cluster reform at China University of Geosciences (Wuhan) as a case study, this paper presents an integrated model of Curriculum System Reconstruction, Digital Intelligence Empowerment, and Teacher Development. By comprehensively restructuring course content, leveraging knowledge graphs and virtual simulation platforms, and implementing a Competition-Research Dual Promotion program for faculty, the model achieves systematic knowledge integration, intelligent teaching innovation, and sustained faculty capacity enhancement. Results demonstrate substantial improvement in students’ higher-order cognitive and innovative practical abilities, effective alignment between course clusters and professional programs, and the creation of a replicable, scalable model for geoscience digital education transformation. This approach provides strategic guidance for cultivating top-tier, innovative geoscience talents equipped for future challenges. 


Volcanic Rocks and Rare-metal Mineralization

XIE Lei, ZENG Gang, CHE Xudong

2026, 32(03):  457-470.  DOI: 10.16108/j.issn1006-7493.2026077

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Volcanic rocks play a fundamental role in transferring materials and energy from the deep Earth to the surface and provide an important link between the Earth’s interior and exterior systems. Because volcanic eruptions are commonly associated with extensive volatile loss, volcanic rocks have traditionally been considered unfavorable source rocks for rare metal mineralization. However, increasing evidence suggests that highly evolved volcanic systems can concentrate economically important rare metals and, under suitable geological conditions, may independently generate ore deposits. This review summarizes the metallogenic characteristics and ore-forming processes of rare metals (e.g., Sn, Be, Nb-Ta, and Li) associated with felsic volcanic rocks. Representative case studies include the Mexican tin-boron metallogenic belt, the Bolivian tin province, fluorinerich volcanic and subvolcanic systems enriched in Sn-Nb-Ta in South China, volcanic-hosted beryllium deposits along the southeastern coast of China, and volcanic-sedimentary lithium deposits. Through comparison of these mineralization styles, the mechanisms responsible for rare metal enrichment in volcanic environments are evaluated. Meanwhile, this review also discusses the potential effects of mantle-derived magmatism on the migration, partitioning and pre-enrichment of niobium (Nb), such as crustal contamination, carbonate components. The results show that intense magmatic differentiation and volatile enrichment are the key factors controlling rare metal mineralization in volcanic rock systems. Additionally, deep recycled carbonates in the source may facilitate the pre-enrichment of rare metals in mantle-derived magmas. Volcanic systems therefore possess the capacity to form rare metal deposits independently rather than merely representing the volcanic equivalents of intrusive ore-forming systems. Moreover, rare metal enrichment in volcanic rocks may provide a direct record of deep magmatic-hydrothermal processes and serve as an effective exploration indicator for concealed ore bodies in covered regions. Recognition of the ore-forming potential of volcanic systems not only refines current models of rare metal metallogenesis but also offers new opportunities for the exploration of concealed rare metal resources.