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Geochemistry, zircon U–Pb geochrono.ogy, and Hf isotopes of S-type granite in the Baoshan block, constraints on the age and evolution of the Proto-Tethys

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Acta Geochimica 2024年第1期43卷 40-58页

作者： Jianjun Zhang Chuanlong Mou Chendong Liu Yong Zhang Ting Chen Hualiang Li Institute of geological survey East China University of TechnologyNanchang 330013China School of Earth Sciences East China University of TechnologyNanchang 330013China Chengdu geological survey Center Chengdu 610081China School of Water Resources&Environmental Engineering East China University of TechnologyNanchang 330013China

Geochemistry, zircon U–Pb geochrono.ogy, and Hf isotope data for the Early Paleozoic granites in the Baoshan Block reveal the Early Paleozoic tectonic evolution of the Proto-Tethys. The samples are high-K, calcalkaline, strongly peralumino.s rocks with A/CNK values of 1.37–1.46, are enriched in SiO2, K2O, and Rb, and are depleted in Nb, P, Ti, Eu, and heavy rare earth elements,which indicates the crystallization fractionation of the granitic magma. Zircon U–Pb dating indicates that they formed in ca. 480 Ma. The Nansa granites have εHf(t) values ranging from-16.04 to 4.36 with corresponding TC DMages of 2.10–0.81 Ga, which suggests the magmas derived from the partial melting of ancient metasedimentary with mino. involvement of mantle-derived components. A synthesis of data for the Early Paleozoic igneous rocks in the Baoshan block and adjacent(Tengchong,Qiangtang, Sibumasu, Himalaya, etc.) blocks indicates that these blocks were all aligned along the proto-Tethyan margin of East Gondwana in the Early Paleozoic. The Early Paleozoic S-type granites from Nansa were generated in a high-temperature and low-pressure(HTLP) extensional tectonic setting, which resulted from Andean-type orogeny instead of the final assembly of Gondwana or crustal extension in a no.-arc environment. In certain places, an expanding environment may exist in opposition to the tectonic backdrop of the lithosphere’s thickening and shortening, leading the crust to melt and decompress,mantle-derived materials to mix, and a small quantity of peralumino.s granite to emerge.

关键词： Baoshan block Early Paleozoic Granite Geochemistry Zircon Geochrono.ogy Hf isotope

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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 Autono.ous 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 no.th 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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Jet Characteristics and Optimization of a Cavitation no.zle for Hydraulic Fracturing Applications

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Fluid Dynamics & Materials Processing 2024年第1期20卷 179-192页

作者： Yu Gao Zhenqiang Xu Kaixiang Shen Shenzhen South China Sea Oil Econo.ic Development Co. Ltd.Shenzhen518000China Guangzhou Marine geological survey China Geological SurveyGuangzhou511458China National Engineering Research Center of Gas Hydrate Exploration and Development Guangzhou511458China

Hydraulic jetting is a form of fracturing that involves using a high-pressure jet of water to create fractures in the reservoir rock with a no.zle serving as the central component of the hydraulic sandblasting perforation *** this study,the flow behavior of the no.zle is simulated numerically in the framework of a SST k-ωturbulence *** results show that the no.zle structure can significantly influence the jet performance and related cavitation *** orthogonal experiments,the no.zle geometric parameters are optimized,and the following configuration is found accordingly:contraction angle 20°,contraction segment length 6 mm,cylindrical segment diameter 6 mm,cylindrical segment length 12 mm,spread segment length 10 mm,and spread angle 55°.

关键词： Cavitation jet angle no.zle hydraulic characteristics no.zle parameters

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Numerical study of directional heat transfer in composite materials via controllable carbon fiber distribution

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Journal of Central South University 2024年第6期31卷 1945-1955页

作者： SHI Lei HUANG Cun-wen YE Jian-ling WEN Shuang LIU Su-ping LI Fen-qiang ZHOU Tian SUN Zhi-qiang School of Energy Science and Engineering Central South UniversityChangsha 410083China Engineering and Mine geological survey and Monitor Institute of Hunan Province Changsha 410014China

Carbon fiber reinforced polyamide 12(CF/PA12),a new material reno.ned for its excellent mechanical and thermal properties,has drawn significant industry *** the steady-state research to heat transfer,a series of simulations to investigate the heat transfer properties of CF/PA12 were conducted in this ***,by building two-and three-dimensional models,the effects of the porosity,carbon fiber content,and arrangement on the heat transfer of CF/PA12 were examined.A validation of the simulation model was carried out and the findings were consistent with those of the ***,the simulation results using the above models showed that within the volume fraction from 0% to 28%,the thermal conductivity of CF/PA12 increased greatly from 0.0242 W/(m·K)to 10.8848 W/(m·K).The increasing porosity had little influence on heat transfer characteristic of CF/*** direction of the carbon fiber arrangement affects the heat transfer impact,and optimal outcomes were achieved when the heat flow direction was parallel to the carbon *** research contributes to improving the production methods and broadening the application scenarios of composite materials.

关键词： heat transfer thermal conductivity carbon fiber-based composite

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Geochemical and Isotopic Techniques Constraints on the Origin,Evolution,and Residence Time of Low-enthalpy Geothermal Water in Western Wugongshan,SE China

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 801-818页

作者： WANG Luyao LIU Kai MA Yan ZHANG Yaoyao TONG Jue JIA Wuhui ZHANG Shouchuan SUN Junliang Chinese Academy of geological Sciences Beijing 100037China School of Water Resources and Environment China University of Geoscience(Beijing)Beijing 100083China The Fourth geological Brigade of Jiangxi geological Bureau PingxiangJiangxi 337000China

Geothermal resources are increasingly gaining attention as a competitive,clean energy source to address the energy crisis and mitigate climate *** Wugongshan area,situated in the southeast coast geothermal belt of China,is a typical geothermal ano.aly and contains abundant medium-and low-temperature geothermal *** study employed hydrogeochemical and isotopic techniques to explore the cyclic evolution of geothermal water in the western Wugongshan region,encompassing the recharge origin,water-rock interaction mechanisms,and residence *** results show that the geothermal water in the western region of Wugongshan is weakly alkaline,with low enthalpy and mineralization *** hydrochemistry of geothermal waters is dominated by Na-HCO_(3)and Na-SO_(4),while the hydrochemistry types of cold springs are all Na-HCO_(3).The hydrochemistry types of surface waters and rain waters are NaHCO_(3)or Ca-HCO_(3).The δD and δ^(18)O values reveal that the geothermal waters are recharged by atmospheric precipitation at an altitude between 550.0 and 1218.6 *** ratios of maj or solutes and isotopic compositions of^(87)Sr/^(86)Sr underscore the significant role of silicate weathering,dissolution,and cation exchange in controlling geothermal water ***,geothermal waters experienced varying degrees of mixing with cold water during their ***δ^(13)C values suggest that the primary sources of carbon in the geothermal waters were biogenic and ***δ^(34)S value suggests that the sulfates in geothermal water originate from sulfide minerals in the surrounding *** dating using 3H and^(14)C isotopes suggests that geothermal waters have a residence time exceeding 1 kaBP and undergo a long-distance cycling process.

关键词： geothermal water hydrochemistry isotope residence time Wugongshan area

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Harmful evaluation of heavy metals from soil layer to the groundwater: Take the Jilin Hunchun Basin as an example

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China Geology 2024年第1期7卷 116-124页

作者： Xiao-Dong Guo Qiang Liu Hui-Rong Zhang Xu-Fei Shi Chuan-Yu Qin Zhi-Qiang Zhang Shenyang geological survey Center China Geological SurveyMinistry of Natural ResourcesShenyang 110034China Key Laboratory of Black Land Evolution and Ecological Effects Shenyang 110034China New Energy and Environment College Jilin UniversityChangchun 130026China Jilin Hydrogeological survey Institute Changchun 130026China

The continuous enrichment of heavy metals in soils has caused potential harm to *** methods to evaluate the harm of heavy metals in soil to groundwater are lacked in previous *** on the theory of groundwater circulation and solid-liquid equilibrium,a simple and easy-touse flux model of soil heavy metals migrating to groundwater is *** on groundwater environmental capacity,an inno.ative method for evaluating the harm of heavy metals in soil to groundwater is proposed,which has been applied in Hunchun Basin,Jilin Province,*** results show that the fluxes of soil heavy metals into groundwater in the study area are Zn,Cu,As,Pb,Cd,Ni,and Hg in descending *** content of heavy metals in groundwater(As,Hg,Cu,Pb,Zn,Ni,and Cd)in most areas has no. risen to the threshold of environmental capacity within 10 *** harm levels of soil heavy metals to groundwater in the most townships soils are at the moderate level or *** evaluation method can quantify the flux of soil heavy metals into groundwater simply and quickly,determine the residual capacity of groundwater to heavy metals,evaluate the harm level of soil heavy metals to groundwater,provide support for relevant departments to carry out environmental protection of soil and groundwater,and provide a reference to carry out similar studies for related scholars.

关键词： Soil heavy metals As+Hg+Cu+Pb+Zn+Ni+Cd Environmental capacity Groundwater Hazard degree Migration flux model Agricultural geological survey engineering Hunchun Basin Jilin Province

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Characteristics of Paleontological Communities in Surface Sediments of the Southern South China Sea and Their Paleoclimatic and Paleoenvironmental Significance

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Journal of Earth Science 2024年第1期35卷 144-154页

作者： Jing Zhao Li Zhang Xiaoyan Wang Jinglian Ge Min Xu Wei Chen Mao Luo Qianyong Liang Qiuhua Yu Shuaibing Luo Wenkun Qie Key Laboratory of Marine Mineral Resoures Ministry of Natural ResourcesGuangzhou Marine Geological SurveyChina Geological SurveyGuangzhou 511458China National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511458China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China

Understanding the spatial and temporal distribution of different paleontological communities in the southern South China Sea(SCS)is fundamental to explore its paleoclimatic and paleoenvironmental *** this study,foraminifera,pollen and diatoms from 100 surface sediment samples covering 40000 km^(2) of sea floor in the southern SCS were comprehensively investigated in terms of their assemblage and *** results showed the existence of abundant foraminifera and pollen in most of the samples,although diatom communities were relatively *** were dominated by ***,***,***,while diatoms were characterized by ***,*** and ***,indicating a typical tropical marine *** pollen assemblages showed a better reflection of montane rainforest,tropical rainforest and *** spatial differences among foraminifera assemblages may indicate the effect of water depth and a warmer environment in the southeast part of the study area,while the spatial patterns of diatom and pollen assemblages imply the influence of coastal *** study also no.ed that the compositions of paleontological communities in the SCS can vary significantly in a short distance,and synthesized studies on multiple biological groups are needed to reconstruct the Quaternary climate and the oceano.raphic environment.

关键词： southern South China Sea sediments foraminifera diatom pollen

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Comparative study of different machine learning models in landslide susceptibility assessment: A case study of Conghua District, Guangzhou, China

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China Geology 2024年第1期7卷 104-115页

作者： Ao Zhang Xin-wen Zhao Xing-yuezi Zhao Xiao-zhan Zheng Min Zeng Xuan Huang Pan Wu Tuo Jiang Shi-chang Wang Jun He Yi-yong Li Wuhan Center China Geological SurveyMinistry of Natural Resources(Geosciences Innovation Center of Central South China)Wuhan 430205China Guangzhou Institute of geological survey Guangzhou 510080China Hubei Transportation Planning Design Institute Co. LtdWuhan 430050China

Machine learning is currently one of the research hotspots in the field of landslide *** clarify and evaluate the differences in characteristics and prediction effects of different machine learning models,Conghua District,which is the most prone to landslide disasters in Guangzhou,was selected for landslide susceptibility *** evaluation factors were selected by using correlation analysis and variance expansion factor *** four machine learning methods namely Logistic Regression(LR),Random Forest(RF),Support Vector Machines(SVM),and Extreme Gradient Boosting(XGB),landslide models were *** analysis and evaluation of the model were conducted through statistical indices and receiver operating characteristic(ROC)*** results showed that LR,RF,SVM,and XGB models have good predictive performance for landslide susceptibility,with the area under curve(AUC)values of 0.752,0.965,0.996,and 0.998,*** model had the highest predictive ability,followed by RF model,SVM model,and LR *** frequency ratio(FR)accuracy of LR,RF,SVM,and XGB models was 0.775,0.842,0.759,and 0.822,*** and XGB models were superior to LR and SVM models,indicating that the integrated algorithm has better predictive ability than a single classification algorithm in regional landslide classification problems.

关键词： Landslides susceptibility assessment Machine learning Logistic Regression Random Forest Support Vector Machines XGBoost Assessment model geological disaster investigation and prevention engineering

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Responses of Nutrients to the Precipitation Variation and Land Use in Subtropical Monsoonal Small Mountaino.s Rivers:A Case Study of Baixi Watershed

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Journal of Ocean University of China 2024年第2期23卷 383-391页

作者： TIAN Yuan GAO Fei CAO Ke LV Shenghua DUAN Xiaoyong YIN Ping Qingdao Institute of Marine Geology China Geological SurveyMinistry of Natural ResourcesQingdao 266237China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266237China

Small mountaino.s rivers are characterized by large instantaneous fluxes and susceptible to extreme weather events,which can rapidly transport materials into the sea and have a significant impact on the ecological environment of estuaries and *** order to investigate the seasonal characteristics of nutrients in small mountaino.s rivers in the subtropical monsoon region and the output pattern to the sea during heavy precipitation,surveys on the mountaino.s rivers were carried out in Baixi watershed in August 2020(wet season),March 2021(dry season)and June 2021(Meiyu period).The results showed that the dissolved ino.ganic nitrogen(DIN)of the rivers has an average concentration of 752μg L^(−1)in the wet season and 1472μg L^(−1)in the dry *** concentrations of dissolved ino.ganic phosphorus(DIP)in wet season and dry season were 63μg L^(−1)and 51μg L^(−1),*** by the changes of land use in sub-watersheds,DIN concentrations in the mainstream increased from 701μg L^(−1)in the upper reaches to 1284μg L^(−1)in the middle *** rainstorms during the Meiyu period in the watershed caused the pulse runo.f in the *** maximum daily runo.f reached 70 times that before *** maximum daily fluxes of DIN and DIP were 109 and 247 times that before rains,*** view that the watershed experienced several rainstorms in the wet season,the river,with pulse runo.f,carries a large amount of nutrients into the sea in a short time,which will have a significant impact on the environment of Sanmen bay and its adjacent sea.

关键词： small mountaino.s river uneven precipitation rainstorm pulse runo.f nitrogen and phosphorus

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Carbon emission reduction: Contribution of geothermal energy and practice in China

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China Geology 2024年第1期7卷 161-164页

作者： Liang Wang Li-qiong Jia Natural Resources Integrated survey Command Center China Geological SurveyMinistry of Natural ResourcesBeijing 100055China Development and Research Center China Geological SurveyMinistry of Natural ResourcesBeijing 100037China

As a kind of natural energy from the earth’s interior,geothermal energy is characterized by large reserve,wide distribution,good stability,high utilization coefficient,and positive effects of energy-saving and *** is of great significance for promoting green and low-carbon energy transition,reducing greenhouse gas emission,and achieving global climate goals and sustainable econo.ic ***,it has been highly recognized and valued by lots of countries around the world,and has become one of the most important clean energy sources that countries are accelerating to develop and *** potential of the global geothermal energy resource is estimated to be 1.25×1027 J,equivalent to 4.27×10^(16) t of standard coal,among which the geothermal resource between 0 km and 5 km is 1.45×10^(26) J,equivalent to 4.95×1015 t of standard coal(China geological survey,2018).

关键词： energy utilize interior

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