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The composition of magmatic-hydrothermal fluids and their related metal mineralization

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Science China Earth Sciences 2025年第1期68卷 208-225页

作者： Qihai SHU Jun DENG state key laboratory of geological processes and mineral resources School of Earth Sciences and Resources China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences

Magmatic hydrothermal deposits are important sources of many bulk, precious, and rare metals, and have attracted interest from both academic and industrial communities. However, it is still unclear if the major enrichment of the ore-forming metals occurs in the parental magma source region, during the magma evolution, or after the fluid exsolution. Fluid inclusions trapped in hydrothermal minerals crystallized in the early, high-temperature stage before metal precipitation record information close to that of the initially exsolved magmatic fluids, which are helpful in revealing whether the metals have been already significantly enriched prior to the hydrothermal stage. In this study, available compositional data of such early-stage fluid inclusions from magmatic hydrothermal systems globally have been compiled. The results indicate that the concentrations of Cu,Sn, and W respectively from the Cu-, Sn-, and W-mineralized fluids are significantly higher than the hydrothermal systems that do not produce ores with the corresponding metals. This suggests that Cu, Sn, and W could have already been enriched in the magma source and/or magma evolution stage. The Mo concentrations show no difference between Mo-mineralized and Mobarren fluid systems, indicating no significant pre-enrichment in the source region or during the magma evolution. This also implies that an efficient collection of Mo from a large volume of magmas is required to account for the formation of a large Mo deposit. Almost all the hydrothermal fluids contain high concentrations of Fe and Zn-Pb, but only a few of them eventually form Fe or Zn-Pb deposits, reflecting an important role of the hydrothermal evolution process on the selective metal *** above results indicate that different metals are enriched in different stages of a magmatic hydrothermal system, and that the major roles played in the formation of a deposit vary with the metal types. In addition to the metal concentrations in the o

关键词： Magmatic hydrothermal deposits Fluid inclusions LA-ICP-MS Metal enrichment mineralization mechanism

Spatiotemporal evolution of Ediacaran-Cambrian(ca. 551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年

作者： Yan YE Lei ZHANG Can CHEN Shan CHANG Yuhao YI Qinglai FENG state key laboratory of geological processes and mineral resources China University of Geosciences(Wuhan) School of Earth Science China University of Geosciences(Wuhan) Department of Geology Lund University Institute of Sedimentary Geology Chengdu University of Technology key laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural resources Chengdu University of Technology Second geological Brigade of Hubei geological Bureau College of Urban and Environmental Sciences Hubei Normal University Exploration and Development Research Institute SINOPEC Jianghan Oilfield Company

The origin and evolution of sponges have attracted interest, not only because they are among the most basal metazoans, but also because they act as important ecological engineers in the ocean. Previous research suggested that sponge groups diversified quickly during the Cambrian Series 2, while Terreneuvian sponge fossils are conspicuously rare and poorly substantiated. Yet, an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C, ca.551–523 Ma) transitional carbonates/cherts worldwide, particularly in South China, which calls for updated discussions. Ocean oxygenation has been widely proposed to play a critical role in organismal evolution, but its relationship with sponges is unclear and falls into a “chicken-egg” dilemma. In this study, we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous sponges. According to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area, and then potentially expand to the continental shelf and deep basin in the lower Cambrian. In these sections, the abundance, size, and diversity of monaxons increase upwards,followed by the appearance of diaxons, triaxons and then polyactines. Despite the uncertain affinity of the sponge fossils, it is possible that siliceous hexactinellids evolved later than siliceous demosponges, given that the earliest spicule assemblages are exclusively composed of monaxons, which commonly form bundles comparable to modern demosponges. New geochemical data from the Sifangjing section, Guizhou Province and the Yanziqiao section, Hunan Province, South China show that the appearance of sponges usually corresponds to anoxic environment. In addition, we applied the recently proposed Biological Pump, Oxygen and Phosphorus(BPOP) model to trace the evolution of oceanic oxygen concentrations with the radiation of sponges. The results indic

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Underground laboratories · Deep underground observation ·Scientific questions—Insights from observations of multi-physic fields in deep underground labs

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Science China Earth Sciences 2025年

作者： Huiqi REN Yun WANG Chang CHEN Guangyu FU Longqing QIU Lianghui GUO Chengliang XIE Yongsheng HE Heping SUN Jiwen TENG Institute of Defense Engineering Academy of Military Sciences state Kay laboratory of geological processes and mineral resources Key Laboratory of Intraplate Volcanoes and Earthquakes Ministry of Education China University of Geosciences (Beijing) Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences Institute of Geology and Geophysics Chinese Academy of Sciences

This paper presents a comprehensive review on recent development and research conducted in domestic and international underground laboratories. We first introduce the differences in three environments—surface, mountain tunnel cavities and underground coal mine tunnels—by examining cosmic ray background, ambient noises related to gravity and seismic measurement, and electromagnetic noises in magnetic and magnetotelluric measurements. We highlight potential misuse of the term Underground lab or Deep Underground lab when describing observations in different physical fields. We introduce unique features of underground coal mine tunnels in China, such as large spaces, ultra-quiet conditions, and ultra-clean environments. When comparing with mountain tunnel cavities and borehole observations, coal mine tunnel observations have superior long-term stability and high precision. Through observations and comparisons of multi-physic fields at surface and the deep underground, we find that the higher SNR seismic observations conducted in deep underground tunnels in coal mines are beneficial to improve velocity tomography of the solid earth. The gravity observation with a Superconducting Quantum Interference Device(SQUID) makes it possibly to capture slow earthquake, which has not been observed previously in the Chinese mainland. SQUID magnetic observations can detect fluctuations as weak as femto-Tesla(fT), enabling us to explore the attenuation of Schumann Resonance down to the solid Earth. This opens opportunities to investigate the connections between the Earth's magnetic field and the interactions within the human brain and heart. To improve the precision of quantum measurement,we should consider the possible effects of weak magnetic disturbances in deep underground environments. Finally, we discuss the importance of deep underground laboratories, observing facilities and techniques deployed in these laboratories, and their possible connection with respect to “deep space” an

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Variation of singularity of earthquake-size distribution with respect to tectonic regime

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Geoscience Frontiers 2018年第2期9卷 453-458页

作者： Qiu-Ming Cheng Hong-Yun Sun state key lab of geological processes and mineral resources China University of Geosciences state key lab of geological processes and mineral resources China University of GeosciencesWuhan

Frequency-size relation of earthquakes in a region can be approximated by the Gutenberg-Richter law(GR). This power-law model involves two parameters: a-value measuring seismic activity or earthquake productivity, and b-value describing the relation between frequencies of small and large *** spatial and temporal variations of these two parameters, especially the b-value, have been substantially investigated. For example, it has been shown that b-value depends inversely on differential stress. The b-value has also been utilized as earthquake precursor in large earthquake ***, the physical meaning and properties of b-value including its value range still remain as an open fundamental question. We explore the property of b-value from frequency-size GR model in a new form which relates average energy release and probability of large earthquakes. Based on this new form of GR relation the b-value can be related to the singularity index(1-2/3 b) of fractal energy-probability power-law model. This model as applied to the global database of earthquakes with size M ≥ 5 from 1964 to 2015 indicates a systematic increase of singularity from earthquakes occurring on mid-ocean ridges, to those in subduction zones and in collision zones.

关键词： Fractals Singularity Power-law distribution Plate tectonics Mathematical model Spatial distribution

Linking deep CO2 outgassing to cratonic destruction

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National Science Review 2022年第6期9卷 12-22页

作者： Zhao-Xue Wang Sheng-Ao Liu Shuguang Li Di Liu Jingao Liu state key laboratory of geological processes and mineral resources China University of Geosciences

Outgassing of carbon dioxide from the Earth's interior regulates the surface climate through deep *** we examine the role of cratonic destruction in mantle CO2outgassing via collating and presenting new data for Paleozoic kimberlites, Mesozoic basaltic rocks and their mantle xenoliths from the eastern North China Craton（NCC）, which underwent extensive destruction in the early Cretaceous. High Ca/Al and low Ti/Eu and δ26Mg are widely observed in lamprophyres and mantle xenoliths, which demonstrates that the cratonic lithospheric mantle（CLM） was pervasively metasomatized by recycled *** analysis of bubble-bearing melt inclusions shows that redox melting of the C-rich CLM produced carbonated silicate melts with high CO2content. The enormous quantities of CO2in these magmas,together with substantial CO2degassing from the carbonated melt–CLM reaction and crustal heating,indicate that destruction of the eastern NCC resulted in rapid and extensive mantle CO2emission, which partly contributed to the early Cretaceous greenhouse climate episode.

关键词： carbonate metasomatism lithospheric mantle CO_2 outgassing deep carbon cycling cratonic destruction North China Craton

Hydration effects on crystal structures and equations of state for silicate minerals in the subducting slabs and mantle transition zone

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Science China Earth Sciences 2016年第4期59卷 707-719页

作者： YE Yu state key laboratory of geological processes and mineral resources China University of Geosciences

There are potentially huge amounts of water stored in Earth's mantle, and the water solubilities in the silicate minerals range from tens to thousands of part per minion(ppm, part per million). Exploring water in the mantle has attracted much attention from the societies of mineralogy and geophysics in recent years. In the subducting slab, serpentine breaks down at high temperature, generating a series of dense hydrous magnesium silicate(DHMS) phases, such as phase A, chondrodite, clinohumite, etc. These phases may serve as carriers of water as hydroxyl into the upper mantle and the mantle transition zone(MTZ). On the other hand, wadsleyite and ringwoodite, polymorphs of olivine, are most the abundant minerals in the MTZ, and able to absorb significant amount of water(up to about 3 wt.% H_2O). Hence, the MTZ becomes a very important layer for water storage in the mantle, and hydration plays important roles in physics and chemistry of the MTZ. In this paper, we will discuss two aspects of hydrous silicate minerals:(1) crystal structures and(2) equations of state(Eo Ss).

关键词： Hydrous silicate mineral Crystal structure Equation of state(Eo S) Mantle transition zone(MTZ) Wadsleyite Ringwoodite

U-Pb Zircon Ages,Geochemical and Sr-Nd-Hf Isotopic Compositions of Granitoids in Western Songpan-Garze Fold Belt:Petrogenesis and Implication for Tectonic Evolution

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Journal of China University of Geosciences 2009年第4期20卷 681-698页

作者：蔡宏明张宏飞徐旺春 state key laboratory of geological processes and mineral resources China University of Geosciences

Granitoids are widespread in the Songpan-Garze （松潘-甘孜） fold belt, western China. These granitoids provide insight into regional tectono-magmatic events, basement nature and tectonic evolution. However, previous studies mainly focused on the eastern Songpan-Garze fold belt. In this article, five granitoid intrusions from the western Songpan-Garze fold belt have been studied. These intrusions are composed of quartz-diorite and granodiorite. Using LA-ICP-MS zircon dating method, the obtained magma crystallization ages are 219±2 Ma for the quartz-diorite and 216±5 Ma for the granodiorite. The ages, combined with regional geological analyses, show that they formed in a post-coilisional tectonic setting. The quartz-diorite and granodiorite display co-linear variation in their chemical compositions. REE compositions for both the quartz-diorite and granodiorite show strongly fractionated patterns with （La/Yb）N=5.02-18.34 and Eu/Eu^＊=0.44-0.89. The quartz-diorites have initial ^87Sr/^86Sr ratios （Isr） of 0.70929-0.71197 and εNd（t） values of -8.6 to -6.1 and the granodiorites have Isr values of 0.70549-0.70997 and εNd（t） values of -8.3 to -4.3. Zircon Hf isotopic data show εHr（t） values of -3.8 to ＋1.6 for the quartz-diorites and -1.2 to ＋3.0 for the granodiorites. Geochemical and Sr-Nd-Hf isotopic compositions indicate that the quartz-diorites and granodiorites have similar petrogenesis. We suggest that the magmas for the quartz-diorites and granodiorites were derived from partial melting of lower crustal mafic source, resulting from amphibole dehydration melting reaction. The probing of the magma source reveals that the western Songpan-Garze fold belt contains an unexposed continental basement, which is similar to the eastern Songpan-Garze fold belt. Geodynamically, it is proposed that a lithospheric delamination model can account for the magma generation for the quartz-diorites and granodiorites in the western Songpan-Garze fold belt.

关键词： granitoid petrogenesis nature ofbasement geodynamics western Songpan-Garzefold belt.

Synchronization Theory and Tungsten-Polymetallic mineralization Distribution in the Qianlishan-Qitianling Area,Southern Hunan

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Journal of Earth Science 2011年第6期22卷 726-736页

作者：李兵 state key laboratory of geological processes and mineral resources China University of Geosciences

Synchronization is an important frontier in contemporary nonlinear *** has been developed and applied widely in the late 20th ***,it has limited applications in geological science,especially in the study of *** ore formation of fluids is a problem of propaga-tion of chemical waves and the generation of their spatiotemporal *** processes and spatiotemporal structures are the essence and core of all geological *** these ideas as guides,giving a new definition for ＂phase＂ in geochemical dynamics,and selecting the concentration data of 10 elements from stream-sediment samples on a 1：50 000 scale,this article applies the syn-chronization theory to the study of the distribution of tungsten-polymetallic mineralization in the Qianlishan（千里山）-Qitianling（骑田岭） area in southern Hunan（湖南） which is one of the most im-portant metallogenetic districts in the Nanling（南岭） *** results show that there are large ore deposits in Shizhuyuan（柿竹园）,Huangshaping（黄沙坪）,Xianghualing（香花岭）,Qitianling,and other areas,which verifies the present distribution of mineral resources in southern ***,this article holds that the spatiotemporal synchronization of chemical waves plays an important role in the science of metallogenesis：it leads to the regional ore zoning centered at Qitianling,confirms that the Yanshan epoch is the chief ore-forming epoch in southern Hunan,and predicts other prospective areas of specific ores.

关键词： Qianlishan-Qitianling area polymetallic deposits synchronization.

Age, Trace Elements and Hf-Isotope Composition of Zircon in Eclogites from the Sulu UHP Belt, East-Central China: Neoproterozoic Intrusion and Subsequent Paleozoic and Early Mesozoic Metamorphism

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Journal of Earth Science 2010年第5期21卷 598-622页

作者：郑建平汤华云赵军红苏玉平余淳梅魏启荣刘庆生吴秀玲 state key laboratory of geological processes and mineral resources China University of Geosciences

The Sulu （苏鲁）-Dabie （大别） orogen in East-Central China formed during the subduction and collision of the Yangtze block with the North China block in Early Mesozoic （240-225 Ma）. Constraints on the nature and derivation of eclogites, which are a significant component of the orogen, can provide useful information about subduction-zone metamorphism and crust-mantle interaction. The U-Pb ages, Hf-isotope ratios and trace-element compositions of zircons in eclogites from the Jiangzhuang （蒋庄）（Jiangsu （江苏） Province） and Rongcheng （荣成）（Shandong （山东） Province） areas indicate that the protoliths of the eclogites derived from ultramafic-mafic complexes or mafic intrusion in the subducted continental lithosphere. The upper intercept age of 852±10 Ma and high tHf （up to 14.7） of the Neoproterozoic zircons in a Jiangzhuang sample indicate that the protoliths represent products of the Neoproterozoic addition of juvenile materials to the older （i.e., Paleo-Mesoproterozoic） continental crust. The zircon ages of eclogites from both localities mainly record the Triassic （230-220 Ma） metamorphism, consistent with the formation of the Sulu orogen in Early Mesozoic. The lower intercept age of 316±4 Ma in a Jiangzhuang sample suggests that thermal activity relating to the paleo- Tethyan in Late Carboniferous also affected the eclogitic protolith.

关键词： age composition zircon eclogite Sulu UHP terrane East-Central China.