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China Geology 2024年第1期7卷 1-11页

作者： Chang Li Fu Wang Peng Yang Fei-cui Wang Yun-zhuang Hu Yan-lin Zhao Li-zhu Tian Rui-bin Zhao Tianjin Center(North China Center of Geoscience Innovation) China Geological Survey(CGS)Tianjin 300170China Tangshan Hydrological survey and Research Center of Heibei Province Tangshan063000China Key Laboratory of Coast Geo-Environment China Geological SurveyCGSTianjin 300170China Tianjin Key Laboratory of Coast geological Processes and Environmental safety Tianjin 300170China

This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s *** interpretation,geological surveys,and IsO clustering u.s.pervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIs software ***,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEsT *** show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and *** total carbon storage is assessed at 2.11×10^(6) t,with specific regional data *** since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in *** important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove *** study is poised to guide future mangroverelated investigations and conservation strategies.

关键词： Mangrove Wetland Carbon storage Ecological conservation ArcGIs software platform Restoration InVEsT model Quantitative analysis Coastal zone of China

Geochemistry, zircon u–Pb geochronology, 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 geochronology, 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 peraluminous rocks with A/CNK valu.s.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) valu.s.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 minor 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 non-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 peraluminous granite to emerge.

关键词： Baoshan block Early Paleozoic Granite Geochemistry Zircon Geochronology Hf isotope

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 economic ***,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

First Record of Middle Eocene Elephant Ancestors’Footprints in the Gonjo Basin,East Tibet Plateau

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Journal of Earth science 2024年第4期35卷 1224-1235页

作者： Asma Tahir Huazhou Yao Junaid Khan Yangui Li He Zhao Yue Yu Tang Yuan Institute of geological survey China University of GeosciencesWuhan430074China Wuhan Center China Geological SurveyWuhan430205China state Key Laboratory of geological Processes and Mineral Resources Wuhan430078China Chengdu Center China Geological SurveyChengdu610081China Institute of Geographic sciences and Natural Resources Research Chinese Academy of SciencesBeijing100101China

It is the first time that the fossil footprints of a group of Middle Eocene elephant ancestors have been discovered in the Gonjo Basin,East Tibet *** Gonjo Formation is attributed to the Middle Eocene Epoch(u-Pb age=44.7±1.2 Ma)and consists mainly of purplish-red,medium-to coarse-grained sandstones,siltstones interbedded with mu.s.ones,and conglomerates with sedimentary structures like ripple marks,rip-up clasts,and trough-cross bedding,suggesting fluvial-lacustrine *** group of fossil footprints has a characteristic oval-concave shape,and the toe impressions are *** fossil footprints are overstepped with a pockmarked texture resembling Proboscipeda *** than 165 fossil footprints of the group are relatively well-preserved with different diameters,which is evidence of highly social behavior and trackmakers of different ages,including calves,juveniles,adolescents,and *** size frequency of the fossil footprints enabled us to deduce the body mass,shoulder height,and hip-height distribution of the trackmakers that crossed the East Tibet Plateau 44.7 Ma *** trackmakers comprised an estimated average hip-height of 111.8 cm,an average shoulder height of 172.8 cm for males/155.9 cm for females,and an average body mass of approximately 1218.1 kg for males/907.8 kg for *** abundance of fossil footprints reveals that in the Middle Eocene Epoch,the environment was extraordinarily conducive for the elephant ancestors to live in the East Tibet region.

关键词： Proboscipeda enigmatica East Tibet Plateau Gonjo Formation fossil footprints fluvial-lacustrine

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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 discu.s.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 valu.s.of 1.05-1.07,Rittmann indexδvalu.s.of 2.05-2.14,and differentiation index(DI)valu.s.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)valu.s.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

step-over of strike-slip faults and overpressure fluid favor occurrence of foreshocks:Insights from the 1975 Haicheng fore-main-aftershock sequence,China

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Earthquake Research Advances 2024年第1期4卷 36-46页

作者： Xinglin Lei Zhiwei Wang shengli Ma Changrong He geological survey of Japan AISTTsukuba305-8567Japan state Key Laboratory of Earthquake Dynamics Institute of GeologyCEABeijing100029 China

This study analyzed and summarized in detail the spatial and temporal distributions of earthquakes,tidal responses,focal mechanisms,and stress field characteristics for the M 7.3 Haicheng earthquake sequence in February *** foreshocks are related to the main fault and the conjugate faults surrounding the extension step-over in the *** initiation timing of the foreshock clusters and the original time of the mainshock were clearly modulated by the Earth's tidal force and coincided with the peak of dilational volumetric tidal *** a plausible and testable hypothesis,we proposed a fluid-driven foreshock model,by which all observed seismicity features can be more reasonably interpreted with respect to the results of existing *** with some other known examples,the widely existing step-over along strike-slip faults and associated conjugate faults,especially for extensional ones in the presence of deep fluids,favor the occurrence of short-term *** clustered seismicity with characteristics similar to those of the studied case is not a sufficient and necessary condition for large earthquakes to occur under similar tectonic conditions,it undoubtedly has a warning significance for the criticality of the main *** testing would require quantification of true/false positives/negatives.

关键词： Haicheng earthquake seismogenic fault ETAs Foreshock Deep fluid

Planning and construction of Xiong’an New Area(city of over 5 million people):Contributions of China’s geologists and urban geology

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China Geology 2024年第3期7卷 382-408页

作者： Bo Han Zhen Ma Liang-jun Lin Hong-wei Liu Yi-hang Gao Yu-bo Xia Hai-tao Li Xu Guo Feng Ma Yu.s.an Wang Ya-long Zhou Hong-qiang Li Tianjin Center China Geological Survey(North China Center of Geoscience Innovation)Ministry of Natural ResourcesTianjin 300170China Xiong’an urban geological Research Center China Geological SurveyMinistry of Natural ResourcesTianjin 300170China Tianjin Key Laboratory of Coast geological Processes and Environmental safety Tianjin 300170China China Institute of Geo-Environment Monitoring Beijing 100081China Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Center for Hydrogeology and Environmental Geology China Geological SurveyMinistry of Natural ResourcesBaoding 071051China Institute of Geophysical&Geochemical Exploration Chinese Academy of Geological SciencesLangfang 065000China Chinese Academy of geological sciences Beijing 10037China

China established Xiong’an New Area in Hebei Province in 2017,which is planned to accommodate about 5 million people,aiming to relieve Beijing City of the functions non-essential to its role as China’s capital and to expedite the coordinated development of the Beijing-Tianjin-Hebei *** 2017 to 2021,the China geological survey(CGs)took the lead in multi-factor urban geological surveys involving space,resources,environments,and disasters according to the general requirements of“global vision,international standards,distinctive Chinese features,and future-oriented goals”in Xiong’an New Area,identifying the engineering geologic conditions and geologic environmental challenges of this *** achievements also include a 3D engineering geological structure model for the whole area,along with“one city proper and five clusters”,insights into the ecology and the background endowment of natural resources like land,geothermal resources,groundwater,and wetland of the area before engineering construction,a comprehensive monitoring network of resources and environments in the area,and the“Transparent Xiong’an”geological information platform that is open,shared,dynamically updated,and three-dimensionally ***’s geologists and urban geology have played a significant role in the urban planning and construction of Xiong’an New Area,providing whole-process geological solutions for urban planning,construction,operation and *** future urban construction of Xiong’an New Area will necessitate the theoretical and technical support of earth system science(Ess)from various aspects,and the purpose is to enhance the resilience of the new type of city and to provide support for the green,low-carbon,and sustainable development of this area.

关键词： Low Carbon New City Planning and construction Land Geothermal resources Groundwater Wetland underground space Geologic disasters site stability Natural resource Ecosystem geological safety Transparent Xiong’an Resilient city Xiong’an New Area

Airblast evolution initiated by Wangjiayan landslides in the M_(s)8.0 Wenchuan earthquake and its destructive capacity analysis

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China Geology 2024年第2期7卷 237-247页

作者： Yu-feng Wang Qian-gong Cheng Qi Zhu Department of geological Engineering Southwest Jiaotong UniversityChengdu 610031China sichuan Highway Planning SurveyDesign and Research Institute LtdChengdu 610041China

Airblasts,as one common phenomenon accompanied by rapid movements of landslides or rock/snow avalanches,commonly result in catastrophic damages and are attracting more and more scientific *** quantitatively analyze the intensity of airblast initiated by landslides,the Wangjiayan landslide,occurred in the Wenchuan earthquake,is selected here with the landslide propagation and airblast evolution being studied using FLuENT by introducing the Voellmy rheological *** results reveal that:(1)For the Wangjiayan landslide,its whole travelling duration is only 12 s with its maximum velocity reaching 36 m/s at t=10 s;(2)corresponding to the landslide propagation,the maximum velocity,28 m/s,of the airblast initiated by the landslide also appears at t=10 s with its maximum pressure reaching594.8 Pa,which is equivalent to violent storm;(3)under the attack of airblast,the load suffered by buildings in the airblast zone increases to 1300 Pa at t=9.4 s and sharply decreased to-7000 Pa as the rapid decrease of the velocity of the sliding mass at t=10 s,which is seriously unfavorable for buildings and might be the key reason for the destructive collapse of buildings in the airblast zone of the Wangjiayan landslide.

关键词： Landslide Voellmy rheological law 3D FLuENT simulation Airblast Intensity Building destructive collapse Wenchuan earthquake geological hazards survey engineering

Petrogenesis and tectonic implications of the silurian adakitic granitoids in the eastern segment of the Qilian Orogenic Belt,Northwest China

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Acta Geochimica 2024年第1期43卷 72-86页

作者： Jiao-Long Zhao Xiao-Jun Huang Pei-Qing Hu Zhen-Xi Yang Ying Fan Er-Teng Wang Fu-Bo Yang Jing-Yu Zhang school of Earth sciences Key Laboratory of Mineral Resources in Western China(Gansu Province)Lanzhou UniversityLanzhou 730000China Nuclear Industry 247 Brigade Tianjin North China Geological Survey BureauTianjin 301800China Fourth Institute of geological and Mineral Exploration of Gansu Provincial Bureau of Geology and Mineral Resources Jiuquan 735000China

Geodynamic mechanism responsible for the generation of silurian granitoids and the tectonic evolution of the Qilian orogenic belt remains controversial. In this study, we report the results of zircon u–Pb age, and systematic whole-rock geochemical data for the Haoquangou and Liujiaxia granitoids within the North Qilian orogenic belt and the Qilian Block, respectively, to constrain their petrogenesis, and the silurian tectonic evolution of the Qilian orogenic belt. Zircon u–Pb ages indicate that the Haoquangou and Liujiaxia intrusions were emplaced at423 ± 3 Ma and 432 ± 4 Ma, respectively. The Haoquangou granodiorites are calc-alkaline, while the Liujiaxia granites belong to the high-K calc-alkaline *** are peraluminous in composition and have relatively depleted Nd isotopic [ε_(Nd)(t) =(-3.9 – + 0.6)] characteristics compared with regional basement rocks, implying their derivation from a juvenile lower crust. They show adakitic geochemical characteristics and were generated by partial melting of thickened lower continental crust. Postcollisional extensional regime related to lithospheric delamination was the most likely geodynamic mechanism for the generation of the Haoquangou granodiorite, while the Liujiaxia granites were generated in a compressive setting during continental collision between the Qaidam and Qilian blocks.

关键词： silurian adakitic granitoids Petrogenesis Tectonic setting Qilian Orogenic Belt

Geochronology,Geochemistry,and sr-Nd-Hf Isotopes of the Diorite Porphyrites from the Weining Beishan Area,Ningxia Hui Autonomous Region:Constraints on Their source and Tectonic Implications

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Journal of Earth science 2024年第2期35卷 462-475页

作者： Anlu Liu Lianfu Hai Jinke Liu Xiaojun Zhang Haifeng Li Fengshun Zhao Guoliang Zhao Jinhe Bai Yifu Museum China University of GeosciencesWuhan430074China school of Earth Resources China University of GeosciencesWuhan430074China Mineral geological survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China National Demonstration Center for Experimental Mineral Exploration Education China University of GeosciencesWuhan430074China Coal geological survey Institute of Ningxia Hui Autonomous Region Yinchuan750021China Zhuhai Engineering Investigation Institute of Guangdong Province Zhuhai519000China

The Weining Beishan area of Ningxia Hui Autonomous Region is located at on the western edge of the Helanshan tectonic belt,which is a tectonic joint among Alxa Block,Ordos Block,and North Qilian orogenic ***,the tectonic evolution of this area remains unclear due to the lack of magmatic *** paper conducted researches on geochronology,geochemistry,and sr-Nd-Hf isotopes of the diorite porphyrites exposed in the Weining Beishan *** zircon u-Pb dating yields two ages of 145.0±1.1 and 146.2±1.5 Ma,and the whole-rock geochemical data indicate that the diorite porphyrites are metaluminous to weakly peraluminous and high-K calc-alkaline *** characteristics of highly initial^(87)sr/^(86)sr ratios(0.70816 to 0.71047),negativeε_(Nd)(t)(−8.9 to−8.4),and negativeε_(Hf)(t)(−13.8 to−21.2)indicate that the diorite porphyrites originated from partial melting of the middle-lower ancient crust related to the North China *** with the regional geology,we suggested that partial melting was triggered by a tectonic activity of deep faults cutting through the crust under the regional stress transformation from compressing to extension during the Late Jurassic–Early Cretaceous,which is probably related to the westward subduction of the Paleo-Pacific Plate.

关键词： zircon u-Pb dating sr-Nd-Hf isotopes magma source diorite porphyrite Weining Beishan area Ningxia Hui Autonomous Region geochronology geochemistry