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A typical paleochannel-controlled ground fissure in Hengshui， Hebei Plain， China

Journal of Earth Science 2024年

作者： Feiyong Wang Jianbing Peng Jishan Xu Quanzhong Lu School of Geology engineering and Geomatics， Chang'an University Key Laboratory of Western China's Mineral resources and geological engineering， Ministry of Education， Chang'an University Key Laboratory of Earth Fissures geological Disaster， Ministry of Natural resources (geological Survey of Jiangsu Province) School of engineering and Technology， Institute of Geosafety， China University of Geosciences， Beijing School of resources and Geosciences， China University of Mining and Technology

Nearly 1 100 fissures have formed on the Hebei Plain in China. Within the Yellow River-Qinghe River-Zhanghe River shallow buried paleochannel Band on the plain， 93 ground fissures controlled by paleochannels have developed. Among them， The Wuyi-Fuping ground fissure is a typical paleochannel-controlled fissure located in Hengshui， Hebei Province， with a total length of 3 km， a dominant strike of NE78°， and nearly upright in the shallow layer. The surface damage observed in this fissure primarily manifests as beaded pits， and its activity showcases distinct segmentation characteristics. On the trench profiles， the offset distance of shallow layers remains consistently around 20 cm within the depth range of 0 m to -3 m. An evident flexure is observed in the strata at depths ranging from -4.5 to -7 m. The drilling profile reveals that there is an absence of dislocations in the deeper strata. Nonetheless， the shallow seismic physical profiles unveil the presence of underlying faults beneath the study area， underscoring the intricate formation process and genesis mechanism of the Wuyi-Fuping ground fissure. Firstly， the formation and evolution of the Qingling River’s paleochannel were shaped by the actions of fault blocks and underlying faults. The interplay of the regional stress field， fault block movement， and fault activity played pivotal roles in driving the development of this paleochannel. Secondly， the paleochannel exerts a controlling influence on the development location and severity of the fissure. During pumping， the confined aquifer within the paleochannel undergoes water loss and compression， resulting in the formation of a surface subsidence funnel. When the tensile stress surpasses the soil’s tensile strength at the funnel’s edge， the soil fractures， giving rise to a ground fissure. Finally， large amounts of surface water generated by heavy rainfall and irrigation can cause existing hidden ground fissures to rupture， emerge， and expand. This paper provide

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Identification of carbonates with high positive carbon isotope excursion from the Liaohe Group in the northeastern North China Craton and implications for the Lomagundi-Jatuli Event

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Science China Earth Sciences 2024年第9期67卷 2824-2844页

作者： Hongyu WANG Shuanhong ZHANG Sen WANG Linghao KONG Yue ZHAO Qiqi ZHANG Sen GAO Guohui HU Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural ResourcesBeijing 100081China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100037China School of Earth Science and Mineral resources China University of GeosciencesBeijing 100083China

The Great Oxidation Event(GOE)during the early Paleoproterozoic represents the first significant buildup in Earth’s atmospheric oxygen and resulted in a series of significant changes in the Earth’s surface *** them is the 2.22(or 2.33)–2.06 Ga Lomagundi-Jatuli Event(LJE),which is globally,the largest magnitude and longest duration,marine carbonate positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)*** event has attracted the attention of scholars all over the ***,except for a high positive carbon isotope excursion(δ^(13)C_(V-PDB)>10‰)recently identified from marine carbonate rocks within the Daposhan Formation in the lower Fanhe Group(or the Sanchazi Group)in the Longgang Block in the northeast North China Craton(NCC),Paleoproterozoic carbonates in the NCC are characterized by a low-amplitude positive carbon isotope excursion(δ^(13)C_(V-PDB)10‰)of marine carbonate rocks occurred at about 2.15 *** co

关键词： Lomagundi-Jatuli Event(LJE) Great Oxidation Event(GOE) Carbon-oxygen isotopes Liaohe Group Marine carbonate Jiao-Liao-Ji Belt North China Craton

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Geochemistry and Zircon U-Pb and Hf Isotopes of Early Devonian Hardawu Granites in the Eastern Segment of the Ultrahigh-Pressure Metamorphic Belt, Northern Qaidam Basin

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Journal of Earth Science 2024年第3期35卷 866-877页

作者： Hua Li Ming Wang Jiqing Li Haikui Tong Jiaxiang Dong Minggang Tian Xiaolin Chen Leguang Li Ting Xie Xiong Li Yuying Che Qinghai geological Survey Xining 810000China Technology Innovation Center for Exploration and Exploitation of Strategic Mineral resources in Plateau Desert Region Ministry of Natural ResourcesXining 810000China Qinghai geological Survey Institute Xining 810000China geological Exploration Institute of Shandong Zhengyuan Jinan 271000China School of Earth Science China University of GeosciencesWuhan 430074China

The Hardawu granites in the eastern segment of the ultrahigh-pressure metamorphic belt,the northern Qaidam Basin,were studied by whole-rock major and trace elements and in-situ zircon U-Pb geochronology and Hf isotopes to discuss the petrogenesis and tectonic *** results show that the granites have a crystallization age of 401±3 Ma,suggesting that they were formed in the Early *** granites have SiO2 contents of 75.32 wt.%-76.05 wt.%,total alkali contents of 8.23 wt.%-8.36 wt.%,and K2O/Na2O ratios of *** were rich in K2O,poor in TiO2,MnO,MgO,and P2O5,and have A/CNK values of 1.05-1.07,Rittmann indexδvalues of 2.05-2.14,and differentiation index(DI)values of *** are high potassium calc-alkaline,weakperaluminum,and highly differentiated I-type *** granites also show enrichment of large ion lithophile elements(LILE)such as Rb,Ba,and Th,and depletion of high field strength elements(HFSE)such as Nb,Ta,and *** total REE concentrations range from 169 ppm to 232 ppm,with enrichments of light rare earth elements and negative Eu anomalies(δEu=0.39-0.55).The zirconεHf(t)values range from-0.65 to-2.29,and the two-stage model ages(tDM2)changed within a small range of 1.44 to 1.54 Ga,indicating that the magma of the Hardawu granites was originated from the partial melting of Mesoproterozoic lower crustal *** with previous studies,we suggest that the Hardawu granites were formed in the extensional tectonic setting after the collision between the Qaidam Block and the central and southern Qilian Block in the Early Devonian.

关键词： granite Early Devonian petrogenesis tectonic implication Qaidam Basin geochemistry

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Defect engineering in N-doped OMC for lightweight and high-efficiency electromagnetic wave absorption

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Journal of Materiomics 2024年第1期10卷 190-199页

作者： Panpan Zhou Jing Zhang Zhi Song Yawei Kuang Yushen Liu Lixi Wang Qitu Zhang School of Electronic and Information engineering Changshu Institute of TechnologyChangshu215500China College of Materials Science and engineering Nanjing Tech UniversityNanjing211816China China geological Survey Nanjing CenterNanjing210016China Supervision and Testing Center of East China Mineral Resources of the Ministry of Land and ResourcesNanjing210016China

Developing low density and efficient dielectric loss materials has become a research hotspot,which can greatly meet the demands of modern radars and settle the problem of electromagnetic wave ***,a series of N-doped ordered mesoporous carbon(OMC)materials with different nitrogen content were prepared via a modified self-assembly method and defect engineering in subsequent calcination *** was discovered that the content and type of nitrogen doping can be effectively modulated by the amount of precursor dicyandiamide,resulting in the changes in porous structure,carbon defects,electromagnetic properties,microwave absorption(MA)performance and radar cross section(RCS)reduction ***,as-fabricated OMC/N2.5 displays ideal MA performance,whose minimum reflection loss(RL(min))value reaches−35.3 dB at 7.76 GHz(3.0 mm)and its effective absorption bandwidth reaches 3.52 GHz(10.64-14.16 GHz,2.0 mm).Furthermore,the optimal RCS reduction values can be obtained as 12.01 dB·m^(2) when the detection theta is 30°,which validly reduces the chances of being detected by ***,this work opens up a novel way for the development of lightweight and high-efficiency MA materials.

关键词： OMC N-doped Defect engineering RCS simulation Microwave absorption

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Analysis of debris flow control effect and hazard assessment in Xinqiao Gully,Wenchuan M_(s)8.0 earthquake area based on numerical simulation

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China Geology 2024年第2期7卷 248-263页

作者： Chang Yang Yong-bo Tie Xian-zheng Zhang Yan-feng Zhang Zhi-jie Ning Zong-liang Li Chinese Academy of geological Sciences Beijing 100037China Chengdu Center of China geological Survey China Geological SurveyChengdu 610081China Technology innovation center for risk prevention and mitigation of geohazard Ministry of Natural ResourcesChengdu 611734China Observation and Research Station of Chengdu geological Hazards Ministry of Natural ResourcesChengdu 610000China

Xinqiao Gully is located in the area of the 2008 Wenchuan M_(s)8.0 earthquake in Sichuan province,*** on the investigation of the 2023"6-26"Xinqiao Gully debris flow event,this study assessed the effectiveness of the debris flow control project and evaluated the debris flow *** field investigation and numerical simulation methods,the indicators of flow intensity reduction rate and storage capacity fullness were proposed to quantify the effectiveness of the engineering measures in the debris flow *** simulation results show that the debris flow control project reduced the flow intensity by41.05%to 64.61%.The storage capacity of the dam decreases gradually from upstream to the mouth of the gully,thus effectively intercepting and controlling the debris *** evaluating the debris flow of different recurrence intervals,further measures are recommended for managing debris flow events.

关键词： Landslide Debris flow Hazard assessment Numerical simulation OpenLISEM Prevention and control project Wenchuan M_(s)8.0 earthquake Xinqiao Gully Sichuan province geological hazards survey engineering

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Hydrochemical Characteristics and Evolution of Underground Brine in Lop Nur,Northwestern China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 786-800页

作者： BO Ying LIU Chenglin JIAO Pengcheng LU Fenglin ZHANG Hua MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China

Lop Nur is located at the eastmost end of the Tarim Basin in Xinjiang,Northwestern *** study reviews the hydrochemical characteristics and evolution of underground brine in Lop Nur,based on analytical data from 429 water samples(mainly brine).It is found that in the NE-SW direction,from the periphery to the Luobei sub-depression,while the hydrochemical type varies from the sodium sulfate subtype(S)to the magnesium sulfate subtype(M),the corresponding brine in the phase diagram transfers from the thenardite phase(Then)area,through the bloedite phase(Blo),epsomite phase(Eps),picromerite phase(Picro),finally reaching the sylvite phase(Syl)*** for the degree of evolution,the sequence is the periphery

关键词： brine evolution isotope enrichment potassium Lop Nur

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Failure evaluation and control factor analysis of slope block instability along traffic corridor in Southeastern Tibet

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Journal of Mountain Science 2024年第6期21卷 1830-1848页

作者： LIU Changqing BAO Han LAN Hengxing YAN Changgen LI Changbo LIU Shijie School of Highway Chang'an UniversityXi'an 710064China State Key Laboratory of resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of geological engineering and Geomatics Chang'an UniversityXi'an 710054China

The instability of slope blocks occurred frequently along traffic corridor in Southeastern Tibet(TCST),which was primarily controlled by the rock mass structures.A rapid method evaluating the control effects of rock mass structures was proposed through field statistics of the slopes and rock mass structures along TCST,which combined the stereographic projection method,modified M-JCS model,and limit equilibrium *** instabilities of slope blocks along TCST were then evaluated rapidly,and the different control factors of instability were *** showed that the probabilities of toppling(5.31%),planar(16.15%),and wedge(35.37%)failure of slope blocks along TCST increased *** instability modes were respectively controlled by the anti-dip joint,the joint parallel to slope surface with a dip angle smaller than the slope angle(singlejoint),and two groups of joints inclined out of the slope(double-joints).Regarding the control effects on slope block instability,the stabilization ability of doublejoints(72.7%),anti-dip joint(67.4%),and single-joint(57.6%)decreased sequentially,resulting in different probabilities of slope block ***,nearby regional faults significantly influenced the joints,leading to spatial heterogeneity and segmental clustering in the stabilization ability provided by joints to the slope ***,the stability of slope blocks gradually weakened as they approached the fault *** paper can provide guidance and assistance for investigating the development characteristics of rock mass structures and the stability of slope blocks.

关键词： Slope engineering Block instability Rapid evaluation method Rock mass structure Control factor

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Dynamic Characteristics of the Long Runout Rock-ice Avalanche at High Altitude——A Case from the Zelongnong Basin, Eastern Himalayan Syntaxis, China

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Acta Geologica Sinica(English Edition) 2024年第5期 1376-1393页

作者： GAO Shaohua YIN Yueping LI Bin GAO Yang ZHANG Nan ZHANG Tiantian GAO Haoyuan LIU Xiaojie Institute of Geomechanics Chinese Academy of Geological Sciences China Institute of geological Environment Monitoring Key Laboratory of Active Tectonics and geological Safety Ministry of Natural Resources School of Civil engineering Lanzhou University of Technology

Rock-ice avalanches have frequently occurred in the Eastern Himalayan Syntaxis region due to climate change and active tectonic movements. These events commonly trigger catastrophic geohazard chains, including debris flows, river blockages, and floods. This study focuses on the Zelongnong Basin, analyzing the geomorphic and dynamic characteristics of high-altitude disasters. The basin exhibits typical vertical zonation, with disaster sources initiating at elevations exceeding 4000 m and runout distances reaching up to 10 km. The disaster chain movement involves complex dynamic effects, including impact disintegration, soil-rock mixture arching, dynamic erosion, and debris deposition, enhancing understanding of the flow behavior and dynamic characteristics of rock-ice avalanches. The presence of ice significantly increases mobility due to lubrication and frictional melting. In the disaster event of September 10, 2020, the maximum flow velocity and thickness reached 40 m/s and 43 m, respectively. Furthermore, continuous deformation of the Zelongnong glacier moraine was observed, with maximum cumulative deformations of 44.68 m in the distance direction and 25.96 m in the azimuth direction from March 25, 2022, to August 25, 2022. In the future, the risk of rock-ice avalanches in the Eastern Himalayan Syntaxis region will remain extremely high, necessitating a focus on early warning and risk mitigation strategies for such basin disasters.

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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China

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China Geology 2024年第3期7卷 469-479页

作者： Jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang Institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural resources Elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

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Genesis of the Shijia Gold Deposit， Jiaodong Peninsula， China: Constraints from Fluid Inclusions and Stable Isotopes

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Journal of Earth Science 2024年

作者： Liqiang Feng Ruiwen Shen Xuexiang Gu Yongmei Zhang Zhanlin Ge Yingshuai Zhang Yu He Natural resources Comprehensive Survey Command Center China geological Survey Ha'erbin Natural resources Survey Command Center China geological Survey School of Earth Sciences and resources， China University of Geosciences State Key Laboratory of geological Processes and Mineral resources， China University of Geosciences Beijing Xi'an Mineral resources Survey Center China geological Survey Department of Natural resources of Liangshan Yi Autonomous Prefecture

The Shijia gold deposit， situated in Penglai City， Shandong Province， is distinguished by its fracture-filling auriferous quartz-sulfide veins. Studies of fluid inclusions and stable isotopes （H-O-C-S） were conducted on this deposit， revealing that the auriferous quartz primarily contains four types of fluid inclusions: CO2-H2O inclusions， pure CO2inclusions， two-phase aqueous inclusions， and solid mineral-bearing multiphase inclusions. The ore-forming fluids of Shijia belong to a heterogeneous H2O-CO2-NaCl system， characterized by moderate to high temperatures （187–386 ℃）， low to high salinities (0.2%–41.2% NaCleq)， and low densities (0.72–1.07 g/cm3). Fluid immiscibility and fluid-rock interaction may have occurred at Shijia， with mineralization depths ranging from 3.3 to 3.9 km. The δD and δ18OH2Ovalues of auriferous quartz vary from -86.1‰ to -79.1‰ and from 9.4‰ to 10.5‰， respectively， suggesting that the ore-forming fluids are of magmatic origin. Carbon isotope compositions of the hydrothermal calcite （-3.31‰ to -0.86‰） indicate the carbon might be related to a mantle source that was contaminated by marine carbonates. The positive δ34S values of sulfides （4.3‰–7.3‰） reflect that the ore-forming materials may be sourced from the metasomatized lithospheric mantle beneath the North China Craton， related to the subduction of the Yangtze Craton in the Triassic. Collectively， the evidence from geology， fluid inclusion and H-O-C-S isotopes indicate that the Shijia gold deposit is of magmatic-hydrothermal origin and related to the Guojialing granite formed by the mixing of crust- and mantle-derived magmas.

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