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The origin and evolution of Earth's nitrogen

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National Science Review 2024年第06期11卷 56-75页

作者： Yuan Li State key laboratory of Isotope {2. Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on Earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth's nitrogen is still incomplete. This review presents an overview of the current understanding of Earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. Like Earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen in{2.sing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

Unraveling the mysteries of volatile cycling and habitability on Earth and beyond

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National Science Review 2024年第06期11卷 8-9页

作者： Yi-Gang Xu Ri-Xiang Zhu Min-Han Dai State key laboratory of Isotope {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences State key laboratory of Lithosphere Evolution Institute of Geology and Geophysics Chinese Academy of Sciences State key laboratory of Marine Environmental Science Xiamen University

The origin and cycling of volatiles, including water, carbon dioxide, and nitrogen, are fundamental to the very existence of habitable planets. These volatile compounds, often taken for granted,are the lifeblood of planetary systems, influencing almost everything from atmospheric composition and climate regulation to deep Earth processes and the emergence of life.

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Assessment of tree-ring mercury radial translocation and age effect in Masson pine:Implications for historical atmospheric mercury reconstruction

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Journal of Environmental Sciences 2024年第4期138卷 266-276页

作者： Xu Liu Xun Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China State key laboratory of Environmental {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

The tree ring has been regarded as an emerging archive to reconstruct historical atmospheric mercury(Hg)trends,but with the large knowledge gaps in the *** this study,we comprehensively evaluated the Hg source,radial translocation and age effect of Masson pine(Pinus massoniana)tree ring at *** in Chongqing,to assess the suitability of such tree ring as the archive of atmospheric *** showed that distinct variabilities among Masson pine tree-ring Hg concentration *** Hg concentration significantly increased along with stem height(P<0.05),indicating the Hg in tree rings mainly derived from foliage uptake atmospheric *** found a distinct age effect that the tree ring of young trees had the higher Hg ***,we used the advection-diffusion model to demonstrate how Hg concentration shifted by the advection or/and diffusion in tree *** modeling results showed that the advection induced radial translocation during the young growth period of tree was a plausible mechanism to result in the tree-ring Hg record largely different from the trend of anthropogenic Hg emissions in *** finally suggest that in further Hg dendrochemistry,better discarding the tree-ring Hg profile of the young growth period to reduce impacts of the radial translocation and age effect.

关键词： Masson pine Tree-ring mercury Radial translocation Tree age effect

Early Ordovician-Middle Silurian Subduction-Closure of the Proto-Tethys Ocean:Evidence from the Qiaerlong Pluton at the Northwestern Margin of the West Kunlun Orogenic Belt,NW China

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Journal of Earth Science 2024年第2期35卷 430-448页

作者： Jinhong Xu Zhengwei Zhang Chengquan Wu Taiyi Luo Weiguang Zhu Xiyao Li Ziru Jin Pengcheng Hu State key laboratory of Ore Deposit {2. Institute of GeochemistryChinese Academy of SciencesGuiyang550018China University of Chinese Academy of Sciences Beijing100049China

Early Paleozoic magmatism in the West Kunlun Orogenic Belt(WKOB)preserves important information about the tectonic evolution of the Proto-Tethys *** paper reports whole-rock compositions,zircon and apatite U-Pb dating,and zircon Hf isotopes for the Qiaerlong Pluton(QEL)at the northwestern margin of WKOB,with the aim of elucidating the petrogenesis of the pluton and shedding insights into the subduction-collision process of this oceanic *** QEL is mainly composed of Ordovician quartz monzodiorite(479±3 Ma),quartz monzonite(467–472.Ma),and syenogranite(463±4 Ma),and is intruded by Middle Silurian peraluminous granite(42.±2. Ma)and diabase(42.±4 Ma).Zirconε_(Hf)(t)values reveal that quartz monzodiorites(+2.1 to+9.9)and quartz monzonites(+0.6 to+6.8)were derived from a mixed source of juvenile crust and older lower crust,and syenogranites(−5.6 to+4.5)and peraluminous granites(−2.9 to+2.0)were generated from a mixed source of lower crust and upper crust;diabases had zirconε_(Hf)(t)values ranging from−0.3 to+4.1,and contained 463±5 Ma captured zircon and 1048±39 Ma inherited zircon,indicating they originated from enriched lithospheric mantle and were contaminated by crustal *** Ordovician granitoids are enriched in LILEs and light rare-earth elements,and depleted in HFSEs with negative Nb,Ta,P,and Ti anomalies,suggesting that they formed in a subduction *** Silurian peraluminous granites have the characteristics of leucogranites with high SiO_(2.contents(74.92.wt.%–75.88 wt.%)and distinctly negative Eu anomalies(δEu=0.03–0.14),indicating that they belong to highly fractionated granite and were formed in a post-collision extension *** analysis of these results with other Early Paleozoic magmas reveals that the Proto-Tethys ocean closed before the Middle Silurian and its southward subduction resulted in the formation of QEL.

关键词： subduction-closure Qiaerlong Pluton West Kunlun Orogen Proto-Tethys Ocean tectonics geochemistry

Melting geodynamics reveals a subduction origin for the Purang ophiolite,Tibet,China

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Acta Geochimica 2024年第4期43卷 754-773页

作者： Tao Ruan Zhong-Jie Bai Wei-Guang Zhu Shi-Ji Zheng State key laboratory of Ore Deposit {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The debate regarding whether the Yarlung-Zangbo ophiolite(YZO)on the south of the Qinghai-Tibet Plateau,formed in a mid-ocean ridge(MOR)or a supra-subduction zone(SSZ)setting has remained *** we present petrological,mineralogical,and geochemical data associated with modeling melting geodynamics of the mantle peridotites from the Purang ophiolite in the western segment of the Yarlung-Zangbo Suture Zone(YZSZ)to explore its tectonic *** Purang lherzolites are characterized by the protogranular texture and have abyssal-peridotite-like mineral compositions,including low Cr^(#)(2.-30)and TiO_(2. contents(2.O_(3)(2.9wt%-4.4wt%)and CaO(1.9wt%-3.7wt%)contents in orthopyroxene and LREE-depletion in *** of these lherzolites can be modeled by~11%dynamic melting of the DMM source with a small fraction of melt(~0.5%)entrapped within the source,a similar melting process to typical abyssal *** Purang harzburgites are characterized by the porphyroclastic texture and exhibit highly refractory mineral compositions such as high spinel Cr^(#)(40-68),low orthopyroxene Al_(2.O_(3)(2.2.t%)and CaO(2.0.4],but depleted in Ti(2.0 ppm,on average)and HREE[(Yb)N2..Importantly,the more depleted samples tend to have higher clinopyroxene Sr and LREE *** observations indicate an open-system hydrous melting with a continuous influx of slab fluid at a subduction *** modeled results show that these harzburgites could be formed by 19%-2.%hydrous melting with the supply rate of slab fluid at 0.1%-1%.The lower clinopyroxene V/Sc ratios in harzburgites than those in lherzolites suggest a high oxidation stage of the melting system of harzburgites,which is consistent with a hydrous melting environment for these *** is therefore concluded that the Purang ophiolite has experienced a transformat

关键词： Melting geodynamics SSZ peridotites MOR peridotites Clinopyroxene Purang ophiolite

Trace elements in magmatic and hydrothermal quartz:Implications on the genesis of the Xingluokeng Tungsten Deposit,South China

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Acta Geochimica 2024年第3期43卷 441-458页

作者： Qing-Qing Zhang You-Wei Chen Jian-Feng Gao State key laboratory of Ore Deposit {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China

The Xingluokeng deposit is the largest gran-ite-related tungsten deposit within the Wuyi metallogenic belt in South *** Xingluokeng intrusion primarily consists of porphyritic biotite granite,biotite granite,andfine-grained *** deposit is represented by veinlet-disseminated mineralization with K-feldspathization and biotitization,alongside quartz-vein mineralization with gre-isenization and *** study investigates in-situ analyses of quartz compositions from both the intrusion and hydrothermal veinlets and *** element correlations indicate that trivalent Al^(3+)and Fe^(3+)replace Si^(4+)within the quartz lattice,with monovalent cations(such as Li^(+),Na^(+),and K^(+))primarily serving as charge *** Ge/Al ratios(<0.013)of quartz from granites suggest a mag-matic *** low Al/Ti and Ge/Ti ratios,accompanied by high Ti contents in quartz,suggest that the porphyritic biotite granite and biotite granite are characterized by rela-tively low levels of differentiation and high crystallization *** contrast,thefine-grained granite exhibits a higher degree of fractionation,lower crystallization tem-peratures,and a closer association with tungsten *** contents in quartz from quartz veins indicate Qz-Ⅰformed at temperatures above 400°C,while Qz-Ⅱto Qz-Ⅴformed at temperatures below 350°*** in different generations of quartz,as indicated by Al content and(Al+Fe)/(Li+Na+K)ratio,suggest that Qz-Ⅰprecipi-tated from a less acidicfluid with a stable pH,whereas Qz-Ⅱto Qz-Ⅴoriginated from a more acidicfluid with notable pH ***,alkaline alteration and acidic alteration supplied the essential Ca and Fe for the precipita-tion of scheelite and wolframite,respectively,highlighting a critical mechanism in tungsten mineralization at the Xin-gluokeng deposit.

关键词： Quartz Xingluokeng Tungsten deposit Trace elements South China

Linkage of mineral inclusions and zoning of magnetite with fluid evolution of hydrothermal systems: A case study of the Fenghuangshan Cu-Fe-Au skarn deposit， Eastern China

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Journal of Earth Science 2024年

作者： Xiao-Wen Huang Yiping Yang Mei-Fu Zhou Yu-Miao Meng Jian-Feng Gao Liang Qi State key laboratory of Ore Deposit {2.， Institute of {2.， Chinese Academy of Sciences CAS key laboratory of Mineralogy and Metallogeny/Guangdong Provincial key laboratory of Mineral Physics and Materials， Guangzhou Institute of geochemistry， Chinese Academy of Sciences

Magnetite from hydrothermal deposits may show compositional zoning with various mineral inclusions in response to the evolution of hydrothermal fluids. Magnetite from the Fenghuangshan Cu-Fe-Au skarn deposit (Eastern China) is a common mineral formed in the earlier stage of skarnization. Magnetite grains have dark gray and light gray zones and contain diverse mineral inclusions. Dark gray zones have higher Si， Ca， Al， and Mg contents than light gray zones. The magnetite matrix from dark gray zones shows superstructure along the [0-11] zone axis in fast Fourier transform patterns， different from magnetite from light gray zones with normal structure. Three types of mineral inclusions are identified within magnetite: nano-， micron- and submicron-nanometer inclusions. Nanoinclusions hosted in dark gray zones are actinolite， diopside， and trace element-rich magnetite， and these are likely formed by growth entrapment during magnetite crystallization at the skarn stage. The chain-width order-disorder intergrowths of diopside nanoinclusion likely indicate fluctuating fluid compositions in a lattice scale. Submicron to nanometer inclusions at the boundary between dark gray and light gray zones are quartz， titanite， and Ti-rich magnetite， which were formed via a dissolution and reprecipitation process at the quartz-sulfide stage. Micron-inclusions randomly distributed in both dark and light gray zones include calcite， ankerite， quartz， and chlorite， and these were formed via penetration of fluids at the carbonate stage. Zoned magnetite was formed by fluid replacement， overgrowth， and fluid infilling. Our study highlights the importance of mineral inclusion assemblages， and textural and chemical zonation of magnetite in constraining fluid evolution.

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In-situ analysis and genetic investigation of Li-bearing minerals in McDermitt clay-type lithium deposit,Nevada,USA

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Acta Geochimica 2024年第3期43卷 478-488页

作者： Yi Cui Hanjie Wen Zhengbing Zhou Kunyue Ling Lin Xu Shirong Liu Fei Xu School of Earth Sciences East China University of TechnologyNanchang 330013China State key laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China School of Earth Sciences and Resources Chang’an UniversityXi’an 710054China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China State key laboratory of Ore Deposit {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China State key laboratory of Environmental {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Clay-type Li deposits are poised to play a pivotal role in addressing the surging global demand for *** McDermitt clay-type Li deposit,located in Nevada,is the largest Li deposit in the United States,with Li hosted by a clay-rich sequence of smectite-dominated intervals and illite-dominated intervals,***,the occurrence of Li and the genesis of Li-bearing minerals within smectite-dominated intervals have not been thoroughly investigated in previous ***,we studied the mineralogy,the in-situ Li distribution,and the bonding environments of Li within the smectite intervals using a combination of instru-mental techniques including scanning electron microscope,transmission electron microscope,time-of-flight secondary ion mass spectrometry,and nuclear magnetic *** results indicate that the smectite exhibits low crystallinity characteristics of lacustrine clay authigenesis and is com-monly found tofill the interstices among volcanic minerals or envelop them;Li is mainly hosted by Mg-smectite rather than the volcanic *** the tuffaceous sediment samples,the volcanic glass has undergone a transformation,resulting in its complete disappearance and alteration into clay *** to the octahedral sites of Mg-smectite bounded in Li,it is referred to be *** interpret that the hectorite’s precipitation occurs in a high saline-alkaline water environment,a result of McDermitt *** conclusion can be supported by the coexistence of spherulitic calcite and ***,this study confirms hectorite as the main Li-bearing mineral and increases the understanding of the genetic model of hectorite formation in intracontinental caldera basins.

关键词： McDermitt caldera Lithium occurrence Tuffaceous sediments Mineralogy Hectorite neoformation

The photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis

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Acta Geochimica 2024年第1期43卷 174-179页

作者： Yanyou Wu Shaogang Guo State key laboratory of Environmental {2. Institute of GeochemistryChinese Academy of SciencesGuiyang 550081People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Photosynthesis is the most important biochemical reaction on Earth. It has co-evolved and developed with the Earth, driving the biogeochemical cycle of all elements on the planet and serving as the only chemical process in nature that can convert light energy into chemical energy. Some heavy oxygen isotopic(^(18)O) labeling experiments have"conclusively" demonstrated that the oxygen released by photosynthesis comes only from water and are written into textbooks. However, it is not difficult to find that bicarbonate has never been excluded from the direct substrate of photosynthesis from beginning to end during the history of photosynthesis research. No convincing mechanism can be used to explain photosynthetic oxygen evolution solely from water photolysis. The bicarbonate effect, the Dole effect, the thermodynamic convenience of bicarbonate photolysis, the crystal structure characteristics of photosystem Ⅱ, and the reinterpretation of heavy oxygen isotopic labeling(^(18)O)experiments all indicate that the photosynthetic oxygen evolution does not exclude the important role and contribution of bicarbonate photolysis. The recently proposed view that bicarbonate photolysis is the premise of water photolysis, bicarbonate photolysis and water photolysis work together with a 1:1(mol/mol) stoichiometric relationship, and the stoichiometric relationship between oxygen and carbon dioxide released during photosynthetic oxygen evolution is also 1:1, has excellent applicability and objectivity, which can logically and reasonably explain the precise coordination between light and dark reactions during photosynthesis, the bicarbonate effect, the Dole effect, the Kok cycle and the neutrality of water and carbon in *** is of great significance for constructing the bionic artificial photosynthetic reactors and scientifically answering the question of the source of elemental stoichiometric relationships in nature.

关键词： Bicarbonate effect Dole effect Kok cycle Heavy oxygen isotope Artificial photosynthetic reactor