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Petrogenesis and Tectonic Implications of the Early Triassic Nianzi Adakitic Granite unit in the Yanshan Fold and Thrust Belt:New Constraints from u-Pb Geochronology and sr-Nd-Hf Isotopes

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Acta Geologica sinica(English Edition) 2024年第1期98卷 50-66页

作者： ZHANG Huijun Wu Chu HE Fubing WANG Biren CuI Yubin LIu Zhenghua YOu.s.ina DONG Jing Development and Research Center of the China geological survey Beijing 100037China Beijing Institute of the geological survey Beijing 100095China Institute of Disaster Prevention LangfangHebei 065201China

The Nianzi granite unit,which includes the Nianzi,Xiaolianghou and Xiawopu granitic intrusions,is a significant component of the northern part of the North China Craton(NCC)and is situated in the Yanshan fold and thrust belt(YFTB).However,there is still debate regarding the tectonic evolutionary history of the YFTB during the late Permian to Triassic period,specifically regarding the timing of subduction and collision between the NCC and the Paleo-Asian *** Nianzi granite unit exhibits unique petrological,geochronological and geochemical signatures that shed light on the tectonic evolutionary history of the *** study presents detailed petrology,whole-rock geochemistry,together with sr-Nd isotopic,zircon u-Pb dating and Lu-Hf isotopic data of the granites within the Nianzi granite *** findings demonstrate that the granites primarily consist of subhedral K-feldspar,plagioclase,quartz,minor biotite and hornblende,with accessory titanite,apatite,magnetite and *** u-Pb dating indicates that the Xiaolianghou granite was emplaced at 247.5±0.62 ***,the adakitic characteristics of the Nianzi,Xiawopu and Xiaolianghou granitic intrusions,such as high sr and Ba contents and high ratios of sr/Y and(La/Yb)N,combined with negative sr-Nd and Lu-Hf isotopes(87sr/86sr)i=0.705681–0.7057433,εNd(t)=−21.98 to−20.97,zirconεHf(t)=−20.26 to−9.92,as well as the I-type granite features of high siO_(2),Na_(2)O and K_(2)O/Na_(2)O ratios,enriched Rb,K,sr and Ba,along with depleted Th,u,Nb,Ta,P and Ti,suggest that the Nianzi granitic unit was mainly derived from the partial melting of a thickened lower crust containing hydrous,calc-alkaline to high-K calc-alkaline,mafic to intermediate metamorphic *** light of these parameters,we further integrate our data with previous studies and conclude that the Nianzi granitic unit was generated in a post-collisional extensional environment during the Early Triassic.

关键词： tectonic evolution zircon geochronology sr-Nd-Hf isotopes Nianzi granite unit Yanshan fold and thrust belt

Genesis of the Nuri Cu-W-Mo Deposit,Tibet,China:Constraints from in situ Trace Elements and sr Isotopic Analysis of scheelite

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Acta Geologica sinica(English Edition) 2024年第1期98卷 117-131页

作者： WANG Yiyun Wu Zhishan CHEN Wenqing Du Qing’an TANG Liwei sHI Hongzhao MA Guotao ZHANG Zhi LIANG Wei Wu Bo MIAO Hengyi Chengdu Center China Geological Survey(Geoscience Innovation Center of Southwest China)Chengdu 610081China The second geological Institute of China’s Metallurgical Geology Bureau Fuzhou 351111China

The Nuri deposit is the only Cu-W-Mo polymetallic deposit with large-scale WO3 resources in the eastern section of the Gangdese metallogenic belt,Tibet,***,the genetic type of this deposit has been controversial since its *** on a study of the geological characteristics of the deposit,this study presents mineralization stages,focusing on the oxide stage and the quartz-sulfide stage where scheelite is mainly formed,referred to as sch-A and sch-B,*** LA-ICP-Ms trace element and sr isotope analyses,the origin,evolutionary process of the oreforming fluid and genesis of the ore deposit are *** Electron Microscope-Cathodoluminescence(sEMCL)observations reveal that sch-A consists of three generations,with dark gray homogenous sch-A1 being replaced by relatively lighter and homogeneous sch-A2 and sch-A3,with sch-A2 displaying a gray CL image color with vague and uneven growth bands and sch-A3 has a light gray CL image color with hardly any growth *** contrast,sch-B exhibits a‘core-rim’structure,with the core part(sch-B1)being dark gray and displaying a uniform growth band,while the rim part(sch-B2)is light gray and *** normalized distribution pattern of rare earth elements in scheelite and sr isotope data suggest that the early ore-forming fluid in the Nuri deposit originated from granodiorite porphyry and,later on,some country rock material was mixed in,due to strong water-rock *** the O-H isotope data further indicates that the ore-forming fluid in the Nuri deposit originated from magmatic-hydrothermal sources,with contributions from metamorphic water caused by water-rock interaction during the mineralization process,as well as later meteoric *** intense water-rock interaction likely played a crucial role in the precipitation of scheelite,leading to varying Eu anomalies in different generations of scheelite from the oxide stage to the quartz-sulfide stage,while also causing a

关键词： trace elements in situ.s. isotopes tungsten mineralization Gangdese metallogenic belt Tibet

Zircon u-Pb ages in the Nuratau ophiolitic mélange in the southern Tianshan,uzbekistan:Implication for the closure of Paleo-Asian Ocean

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China Geology 2024年第2期7卷 365-368,I0004-I0007页

作者： Kai Weng Ji-fei Cao Divayev-Farid Karibovich Jahongir-Jurabekovich Movlanov Bo Chen Zhong-ping Ma Xi’an Center of geological survey China Geological SurveyXi’an 710119China The Center for Geoinnovation Technologies Doctor of sciences in Geology and Mineralogy University of Geological ScienceTashkent 100060Uzbekistan

*** The Central Asian Orogenic Belt(CAOB),which is located between the European craton,siberian craton,and Tarim-North China craton(Fig.1a),is the largest phanerozoic accretionary orogen in the *** resulted from the longterm subduction and accretion of the Paleo-Asian Ocean(PAO).The PAO has been in existence since at least the late Mesoproterozoic(about 1020 Ma).However,there has been debate about the closing time of the PAO.

关键词： Asian Paleo Tianshan

Timing and Tectonic setting of the Gaoaobei TungstenMolybdenum Deposit in Nanling Range, south China

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Journal of Earth science 2024年第3期35卷 890-904页

作者： Jianfeng Li Kemeng Ma Youyue Lu Jianming Fu.s.unbo Cheng Yuan Li Chuanbiao Li College of Geographical science Liaoning Normal UniversityDalian 116029China Wuhan Center of geological survey China Geological SurveyWuhan 430205China Granite Diagenesis and Mineralization Geology Research Center China Geological SurveyWuhan 430205China Mineral Resources survey Institute of Hunan Province Changsha 410083China

The Gaoaobei tungsten-molybdenum deposit is a newly discovered large-scale quartzvein-type deposit in the Nanling metallogenic belt in south *** ore bodies are hosted in the Indosinian granites and the Cambrian Xiangnan Group slates and are controlled by NWW-oriented faults,which are obviously different from the“five-story building”model in southern Jiangxi *** magmatic rocks in the study area are dominated by medium-to coarse-grained biotite monzogranite,with a few NW-oriented fine-grained granite *** medium-to coarse-grained biotite monzogranite and fine-grained granite dykes have zircon u-Pb ages of 229.4±1.9 Ma(MsWD=1.5)and 164.9±3.3 Ma(MsWD=0.75),respectively,corresponding to the Indosinian and Yanshanian *** monzogranites have higher contents of FeO,CaO,K2O,P2O5,and TiO2,while the granite dykes have slightly higher contents of siO2,Al2O3,MnO,and *** A/CNK valu.s.are 1.11-1.75 and 1.19-2.25,and the contents of CIPW normative corundum are 1.71%-6.66%and 2.41%-9.50%,suggesting both the monzogranites and granite dykes are s-type *** total amount of rare earth elements in the monzogranites(from 84.7 ppm to 129 ppm)is slightly lower than that in the granite dykes(from 128 ppm to 133 ppm).The Eu/Eu*valu.s.range from 0.12 to 0.30 in monzogranites and from 0.0011 to 0.0013 in granite dykes,indicating the fine-grained granites underwent more intense fractional *** monzogranite and granite dykes have high 87sr/86sri valu.s.of 0.7169-0.7193 and 0.72825-0.72880,lowεNd(t)valu.s.ranging from-10.2 to-9.6 and from-11.5 to-11.4,and TDM2 ages of 1835-1785 and 1957-1946 Ma,*** isotope data indicate their origin from the remelting of the Paleoproterozoic crustal *** with regional geology,it is concluded that the medium-to coarse-grained biotite monzogranite was formed in a post-collisional extensional *** addition,40Ar-39Ar dating of the greisen type tungsten-molybdenum ore gave

关键词： zircon u-Pb age 40Ar-39Ar age geochemistry tungsten molybdenum deposit Gaoaobei Nanling Range.

The Geology, Fluid Inclusions, and O-s Isotopes of the Mibei Gold Deposit, Hunan Province, southern China

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Acta Geologica sinica(English Edition) 2024年第4期98卷 992-1006页

作者： XuE Wenhao LIANG Yayun LI Xiaofeng LI Mingyi XIE Wenbo PENG Xue XIA Rui HE Hongsheng XIAO Jincheng school of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Geophysical and Geochemical survey Institute of Hunan Changsha 410116China New geological Energy Exploration and Development Engineering Technology Research Center of Hunan Changsha 410116China state Key Laboratory of geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Comprehensive survey Command Center for Natural Resources China Geological SurveyBeijing 100055China

The Mibei gold deposit,located in the southwestern part of the Xuefengshan uplift zone,the middle section of the Jiangnan orogenic belt in southern China,has estimated gold resources of approximately seven *** deposit is primarily a quartz vein-type gold deposit,with ore bodies occurring mainly within Neoproterozoic *** main metallic minerals in the ore are pyrite,chalcopyrite,and *** this study,the petrography and microthermometry of ore-forming fluid inclusions,oxygen isotopes of gold-bearing quartz,and sulfur isotopes of goldbearing sulfides and arsenopyrite were *** types of fluid inclusions were identified:type Ⅰa three-phase inclusions comprising vapor and two phases of liquids(V_(CO_(2))+L_(CO_(2))+L_(H2O)),type Ⅰb two-phase liquids(L_(CO_(2))+L_(H2O)),typeⅡ two-phase vapor-rich inclusions(V/V+L> 50%),and type Ⅲ pure liquid *** Ⅰ inclusions were heated uniformly to the liquid phase,type Ⅱ inclusions were heated uniformly to the gas phase,and type Ⅲ inclusions were heated without *** general,the temperature range of homogenization to liquid phase of fluid inclusions in the Mibei gold deposit is 204-227℃.The salinity of the inclusion ranges from 4.6 to 12.2 wt% NaCl *** δ~(18)O_(sMOW) of gold-bearing quartz varies from 16.9‰ to 17.5‰.The δ~(18)O_(H2O) of gold-bearing quartz are varied from 6.5‰ to 7.5‰.The δ~(34)s valu.s.of gold-bearing pyrite range from 1.7‰ to 6.8‰.The δ~(34)s valu.s.of gold-bearing arsenopy rite range from 5.6%o to 5.9‰.Theδ~(34)s valu.s.of pyrite from wall rocks slate range from 6.4‰ to 11.6‰.This evidence implies that the ore-forming fluids of the Mibei gold deposit originated from magmatic-hydrothermal processes,mixing with minor s from the surrounding *** with the evolution of the Jiangnan orogenic belt,due to the magmatic and tectonic activities of the Xuefengshan uplift during the Caledonian period,the fault seal mechanism controlled the ore-forming p

关键词： ore-forming fluid ore genesis Mibei gold deposit Xuefengshan uplift zone Jiangnan orogenic belt

Novel method for identifying the stages of discharge underwater based on impedance change characteristic

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Plasma science and Technology 2024年第4期26卷 133-145页

作者：高崇康忠健龚大建张扬王玉芳孙一鸣 Department of New Energy China University of PetroleumQingdao 266580People’s Republic of China shanghai Ruida Fengzhi science and Technology Corporation Shanghai 201703People’s Republic of China China National Petroleum Group General Research Institute of Engineering and Technology Corporation Beijing 100029People’s Republic of China Oil and Gas Resource survey Center China Geological SurveyBeijing 100083People’s Republic of China

It is difficult to determine the discharge stages in a fixed time of repetitive discharge underwater due to the arc formation process being susceptible to external environmental influences. This paper proposes a novel underwater discharge stage identification method based on the strong Tracking Filter(sTF) and impedance change characteristics. The time-varying equivalent circuit model of the discharge underwater is established based on the plasma theory analysis of the impedance change characteristics and mechanism of the discharge process. The sTF is used to reduce the randomness of the impedance of repeated discharges underwater, and then the universal identification resistance data is obtained. Based on the resistance variation characteristics of the discriminating resistance of the pre-breakdown, main, and oscillatory discharge stages, the threshold valu.s.for determining the discharge stage are obtained. These include the threshold valu.s.for the resistance variation rate(K) and the moment(t).Experimental and error analysis results demonstrate the efficacy of this innovative method in discharge stage determination, with a maximum mean square deviation of scrless than 1.761.

关键词： discharge underwater discharge stage identification impedance characteristics strong tracking filter

geological conditions and reservoir characteristics of various shales in major shalehosted regions of China

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China Geology 2024年第1期7卷 138-149页

作者： shu-jing Bao Tian-xu Guo Jin-tao Yin Wei-bin Liu.s.eng-jian Wang Hao-han Li Zhi Zhou.s.i-zhen Li Xiang-lin Chen The Key Laboratory of unconventional Petroleum Geology China Geological SurveyMinistry of Natural Resources100083 BeijingChina Oil and Gas survey China Geological Survey100083 BeijingChina Research Institute of Yanchang Petroleum(Group)CO.LTD 710076 Xi’anChina

China is home to shales of three facies:Marine shale,continental shale,and marine-continental transitional *** types of shale gas are associated with significantly different formation conditions and major controlling *** study compared the geological characteristics of various shales and analyzed the influences of different parameters on the formation and accumulation of shale *** general,shales in China’s several regions exhibit high total organic carbon(TOC)contents,which lays a sound material basis for shale gas *** strata generally show high degrees of thermal *** contrast,continental shales manifest low degrees of thermal evolution,necessitating focusing on areas with relatively high degrees of thermal evolution in the process of shale gas surveys for these *** shales of the Wufeng and silurian formations constitute the most favorable shale gas reservoirs since they exhibit the highest porosity among the three types of *** shales are followed by those in the Niutitang and Longtan *** contrast,the shales of the Doushantuo,Yanchang,and Qingshankou formations manifest low ***,the shales of the Wufeng and Longmaxi formations exhibit high brittle mineral *** a low siliceous mineral content,the shales of the Doushantuo Formation feature a high carbonate mineral content,which can increase the shales’brittleness to some *** marine-continental transitional shales,where thin interbeds of tight sandstone with unequal thicknesses are generally found,it is recommended that fracturing combined with drainage of multiple sets of lithologic strata should be employed to enhance their shale gas production.

关键词： shale gas Marine shale Continental shale Marine-continental transitional shale Neoproterozoic-Cretaceous strata geological conditions Reservoir characteristics Petroleum geological survey engineering

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 distingu.s.ed 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 δ18OH2Ovalu.s.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 valu.s.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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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 u.s.ream 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