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Acta Geologica Sinica(English Edition) 2024年第3期98卷 641-656页

作者： WANG Qiuyu CHEN Shouming ZHANG Hongrui LI Saisai SinoProbe Laboratory Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China guangxi Key Laboratory of Hidden Metallic Ore Deposit Exploration GuilinGuangxi 541004China

High-silica granitoids record the formation and evolution of the continental crust.A new intrusive complex has been recognized among silicic volcanic rocks of the Weixi arc,Southwest *** intrusions consist of granites,granitic porphyries,and *** U-Pb age data indicate that the Weixi granitoids formed at 248-240 Ma and were coeval with silicic volcanic rocks of the Weixi *** Weixi granitoids are enriched in Rb,Th,and U,depleted in Ba,Sr,Nb,Ta,and Ti,and have high light/heavy rare earth element ratios and slightly negative Eu *** Weixi granitoids have negative ε_(Nd)(t)values(-9.8 to-7.8)and negative zircon ε_(Hf)(t)values(-12.02 to-5.11).The geochemical and isotopic features suggest the Weixi granitoids were derived by partial melting of ancient crustal *** Weixi granitoids and silicic volcanic rocks were derived from the same magma by crystal accumulation and melt extraction,respectively,and they record the formation of a continental arc in the central Sanjiang orogenic belt.

关键词： granitoids geochemistry crystal accumulation continental crust Sanjiang orogen

Characterization and spatial analysis of coseismic landslides triggered by the Luding Ms 6.8 earthquake in the Xianshuihe fault zone, Southwest China

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Journal of Mountain Science 2024年第1期21卷 160-181页

作者： GUO Changbao LI Caihong YANG Zhihua NI Jiawei ZHONG Ning WANG Meng YAN Yiqiu SONG Deguang ZHANG Yanan ZHANG Xianbing WU Ruian CAO Shichao SHAO Weiwei institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Active Tectonics and geological Safety Ministry of Natural ResourcesBeijing 100081China Research Center of Neotectonism and Crustal Stability China Geological SurveyBeijing 100081China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Sichuan institute of geological survey Chengdu 610081China

On September 5, 2022, a magnitude Ms 6.8 earthquake occurred along the Moxi fault in the southern part of the Xianshuihe fault zone located in the southeastern margin of the Tibetan Plateau,resulting in severe damage and substantial economic loss. In this study, we established a coseismic landslide database triggered by Luding Ms 6.8 earthquake, which includes 4794 landslides with a total area of 46.79 km^(2). The coseismic landslides primarily consisted of medium and small-sized landslides, characterized by shallow surface sliding. Some exhibited characteristics of high-position initiation resulted in the obstruction or partial obstruction of rivers, leading to the formation of dammed lakes. Our research found that the coseismic landslides were predominantly observed on slopes ranging from 30° to 50°, occurring at between 1000 m and 2500 m, with slope aspects varying from 90° to 180°. Landslides were also highly developed in granitic bodies that had experienced structural fracturing and strong-tomoderate weathering. Coseismic landslides concentrated within a 6 km range on both sides of the Xianshuihe and Daduhe fault zones. The area and number of coseismic landslides exhibited a negative correlation with the distance to fault lines, road networks, and river systems, as they were influenced by fault activity, road excavation, and river erosion. The coseismic landslides were mainly distributed in the southeastern region of the epicenter, exhibiting relatively concentrated patterns within the IX-degree zones such as Moxi Town, Wandong River basin, Detuo Town to Wanggangping Township. Our research findings provide important data on the coseismic landslides triggered by the Luding Ms 6.8 earthquake and reveal the spatial distribution patterns of these landslides. These findings can serve as important references for risk mitigation, reconstruction planning, and regional earthquake disaster research in the earthquake-affected area.

关键词： Luding earthquake Coseismic landslides Remote sensing interpretation Spatial distribution Xianshuihe fault Earthquake fault

Quaternary integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 1360-1394页

作者： Yong WANG Mianping ZHENG Yuan LING Shuyuan XIANG Zhaogang SHAO Kexin ZHANG Xue KE Xiao LIN Fang HAN Jian’en HAN institute of Geology Chinese Academy of Geological SciencesBeijing 100037China institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Faculty of Earth Sciences China University of GeosciencesWuhan 430074China Chinese Academy of geological Sciences Beijing 100037China institute of geological survey China University of GeosciencesWuhan 430074China School of Earth Sciences East China University of TechnologyNanchang 330013China institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China

The Quaternary strata on the Qinghai-Tibet Plateau contain rich information about the paleoclimate and environmental evolution,record the evolution process of the Quaternary regional tectonics,paleogeography,and geomorphology of the plateau,and are extremely important areas for studying the Quaternary geological events and regional environmental *** to a comprehensive analysis of the regional stratigraphic data and the development and evolution characteristics of the biota,based on the differences in the lithostratigraphic units,sedimentary characteristics,landforms,and drainage systems,the Quaternary strata on the Qinghai-Tibet Plateau and its surrounding areas are divided into five stratigraphic regions:the Tarim region,Loess Plateau region,Qinghai-Tibet Plateau region,Yunnan-Guizhou Plateau region,and India-Ganges *** Qinghai-Tibet Plateau stratigraphic region is divided into seven stratigraphic sub-regions:the West Kunlun-Karakorum,AltunQilian Mountains,Qaidam-Hehuang,East Kunlun-Bayan Har,Qiangtang,East Xizang-West Yunnan-West Sichuan,and Gangdise-Himalayan *** paper briefly describes the lithostratigraphic units of the seven stratigraphic sub-regions of the Qinghai-Tibet *** to the lithostratigraphic sequence and its sedimentary characteristics,stratigraphic contact relationship,formation age,and evolution of the biota in each stratigraphic sub-region,the Quaternary tectonic paleogeographic evolution of the Qinghai-Tibet Plateau is divided into four stages.(1)The inherited differential uplift stage since the Pliocene(2.6-1.8/1.5 Ma):the regional sedimentary differences were significant,and the stratigraphic distribution was limited,the alluvial-proluvial sandy conglomerate was widely developed along the piedmont,and fluvial and lacustrine deposits were developed in the low-lying areas between the mountains.(2)The mountain range flattening stage(1.8/1.5-1.2/0.8 Ma):the erosion unconformity surfaces around the pl

关键词： Quaternary stratigraphic sedimentary

The Middle and Late Holocene climate change in Bohai Bay revealed by diatom proxy

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Journal of Oceanology and Limnology 2024年第5期42卷 1493-1506页

作者： Zhiwen SHANG Jianfen LI Fu WANG Hong WANG Tianjin Centre China Geological SurveyTianjin 300170China Key Laboratory of Coastal Geo-environment China Geological SurveyTianjin 300170China Tianjin Key Laboratory of Coast geological Processes and Environmental Safety Tianjin 300170China

A total of 98 samples from two boreholes in shallow sea area and two oyster reefs in adjacent coastal plain in the northwestern coast of Bohai Bay were collected for diatom analyses and species *** ratio of the marine species Thalassionema nitzschioides to the intertidal-coastal species complex Cyclotella striata/stylorum serves as a novel proxy for assessing the strength of marine *** data,corrected for the local residence time effect,facilitated the construction of a diatom proxy-based marine influence curve for the study *** curve delineates the dynamics of marine influence and their correlations with paleo-climate fluctuations and the East Asian monsoon variability,as well as their role in chenier *** include:(1)eight periods of intensified marine influence have been documented since 7000 a BP in the study *** peak of each period,as determined by the diatom proxy,corresponds closely to the warm climatic phases and stronger East Asian summer monsoons,suggesting that the peaks marine influence indicate typically the periods of climatic warmth and monsoon activity intensification in the region;(2)a strong correlation exists between the development of cheniers and marine influence,and chenier formation began with the increasing marine influence and terminated at the end of warm periods as marine influence *** climatic changes in the coastal area,as indicated by the diatom proxy,hold significant potential for future related research endeavors.

关键词： Bohai Bay diatom diatom-based marine influence curve paleo-climate Holocene

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

Constraints on crustal compositional architecture across the North China-Altaids transition and implications for craton margin reworking

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National Science Review 2024年第5期11卷 121-133页

作者： Zhuo Ye Xiaomiao Tan Rui Gao Qiusheng Li Hongshuang Zhang Xiaoyang Wu Wenhui Li Yingkang Li Sino Probe Center Chinese Academy of Geological Sciences Key Laboratory of Deep-Earth Dynamics Ministry of Natural Resources Institute of Geology Chinese Academy of Geological Sciences School of Earth Sciences and Engineering Sun Yat-sen University Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of Sciences China geological Sample Information Center China Geological Survey

The phase of secular evolution of continents is manifested as the degree of compositional differentiation,modification and maturation of continental crusts, which is vital in understanding the mechanism of continental evolution but is difficult to quantify. Here we use integrated passive-and active-source seismic profiling to conduct joint analysis and inversion and derive Vs and Vp/Vs section models across the North China Craton(NCC) to southeastern Altaids boundary zone that bears a tectonic transition from a reworked ancient craton margin to a Phanerozoic accretionary orogen. We systematically exploited the imaged multiple physical properties as precise and delicate proxies to constrain the compositional architecture in the crust across this important tectonic transition subject to various crustal evolutional phases. Our Vs and Vp/Vs imaging, together with the existing isotopic data, characterizes the Yin Shan–Yan Shan belt as the northern NCC margin with layered homogeneous compositions that point to an evolved crust. However, the lower-crustal low-Vs/high-Vp/Vs signature that overlaps the shallowly dipping to horizontal reflective fabrics suggests that the crust of the northern NCC margin has undergone considerable reworking through lower-crustal-stretching-assisted melt migration and mixing since the late Paleozoic to Mesozoic eras. The process probably involved crust–mantle interaction and thus resulted in a compositionally modified ancient crustal basement. On the contrary, the southeastern Altaids domain manifests crustal complexity in compositions and structures inferred to be indicative of a juvenile crust of the Phanerozoic accretionary orogen. Our results provide deep physical-property constraints that shed new light on the crustal evolution of a complex craton margin.

关键词： North China Craton Altaids crustal composition receiver function joint inversion continental reworking

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 Sr isotopes tungsten mineralization Gangdese metallogenic belt Tibet

Carbon emission reduction:Contribution of photovoltaic power and practice in China

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China Geology 2024年第2期7卷 371-376页

作者： Liang Wang Li-qiong Jia Geng Xie Xi-jie Chen Yang Liu Natural Resources Integrated survey Command Center China Geological SurveyMinistry of Natural ResourcesBeijing 100055China Development and Research Center China Geological SurveyMinistry of Natural ResourcesBeijing 100037China Center for Geophysical survey China Geological SurveyLangfang 065000China

As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas *** the global t... 详细信息

关键词： convert power emissions

Prediction of Ground Vibration Induced by Rock Blasting Based on Optimized Support Vector Regression Models

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 3147-3165页

作者： Yifan Huang Zikang Zhou Mingyu Li Xuedong Luo Faculty of Engineering China University of GeosciencesWuhan430074China institute of geological survey China University of GeosciencesWuhan430074China

Accurately estimating blasting vibration during rock blasting is the foundation of blasting vibration *** this study,Tuna Swarm Optimization(TSO),Whale Optimization Algorithm(WOA),and Cuckoo Search(CS)were used to optimize two hyperparameters in support vector regression(SVR).Based on these methods,three hybrid models to predict peak particle velocity(PPV)for bench blasting were ***-eight samples were collected to establish the PPV database,eight initial blasting parameters were chosen as input parameters for the predictionmodel,and the PPV was the output *** predictive performance evaluation indicators,the coefficient of determination(R2),rootmean square error(RMSE),mean absolute error(MAE),and a10-index were *** normalizedmutual information value is then used to evaluate the impact of various input parameters on the PPV prediction *** to the research findings,TSO,WOA,and CS can all enhance the predictive performance of the SVR *** TSO-SVR model provides the most accurate *** performances of the optimized hybrid SVR models are superior to the unoptimized traditional prediction *** maximum charge per delay impacts the PPV prediction value the most.

关键词： Blasting vibration metaheuristic algorithms support vector regression peak particle velocity normalized mutual information

Offshore high-grade limemud resources of west coast of India:Economic potential and industrial applications

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Deep Underground Science and Engineering 2024年第2期3卷 163-170页

作者： Anil Kumar Adukadukkam Rachna Pillai Mamatha Puthiyathara Kanakamma Marine&Coastal survey Division Geological Survey of IndiaSalt LakeKolkataWest BengalIndia

Limestone is one of the essential raw materials in the cement,paint,steel,ceramic,glass,chemical,pharmaceutical,paper,and fertilizer *** India,only 8%of the limestone resources are placed under the reserve category,of which 97%is of cement ***,India depends on imports to bridge the demand‐supply gap of steel,blast furnace,and chemical‐grade *** of geological survey of India(GSI)to locate alternate sources for limestone led to the discovery of enormous quantities of carbonate minerals called limemud from the continental shelf margin of the west coast of *** carried out systematic studies to explore the nature of the disposition,quality,quantity,and suitability of the offshore limemud for various industrial applications.A preliminary estimate of resources using high‐resolution subbottom profiling and sediment core sample studies established the occurrence of more than 172 billion tonnes of high‐grade(The content of CaCO3 is greater than 80 wt%)limemud in 0.4–28.0m thick stratified sediment layers spread over an area of 18000 ***,physical,mineralogical,beneficiation,and agglomeration studies found the offshore limemud as a potential replacement for limestone in the cement,filler,blast furnace,steel melting shop,lime production,paint,and Grade‐I steel *** assessment of mining and transportation costs indicates that the offshore limemud(USD 5–6/ton)is more cost‐effective than that imported from other countries(USD16‐18/ton).With several advantageous factors like low impurity,mode of occurrence in overburden‐free stratified form,fine‐grained slurry nature,and shallow water depth,sustainable mining of offshore limemud could be a future reality with controllable technological,economic,and environmental challenges.

关键词： beneficiation industrial grade offshore limemud west coast of India