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Effect of regional land subsidence on engineering structures:a case study of the 6 km long Su-tong Yantze River Bridge

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Effect of regional land subsidence on engineering structures...

Analysis of the Spatio-Temporal Characteristics of Winter Surface Urban Heat Island: A Case Study in beijing, China

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： F.S.Ma·Y.S.Yang·R.M.Yuan·B.K.Yao J.guo Key Laboratory of Engineering Geomechanics,institute of geology and Geophysics,{3. academy of sciences, beijing 100029,People’s Republic of China College of Environment and resources,Jilin University, Changchun 13.026,People’s Republic of China School of Earth Ocean and Planetary sciences, Cardiff University,Cardiff CF10 3.E,UK National Center for Active Fault studies,institute of geology, China Earthquake Administration,beijing 100029, People’s Republic of China institute of {13. survey of Jiangsu Province, Nanjing 210018,People’s Republic of China

The article reports a study of the influence of regional land subsidence on the 6.05 km long Su-tong Yangtze River *** characteristics of the major compressive geological layers and their potential to settlement are discussed in the light of the past and continuing groundwater exploitation in the area.A numerical model for land subsidence quantification was developed and used to predict the differential settlements along the bridge axis to *** is a significant difference in the settlement occurring in the north and south areas of the bridge,in part due to the variation in the Quaternary alluvial sediments. The case study highlights the importance of considering both site specific and regional subsidence conditions when designing large structures in such an area.

关键词： Land subsidence Environmental risk Overexploitation Highway bridge Su-Xi-Chang area

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Journal of Earth Science 2024年第5期35卷 1640-1653页

作者： Shanshan Lu Fujiang Liu Yunshuang Ye Jiayu Tang Peng Li Weihua Lin Yan guo Ruqiang Ma Jun Wang School of Geography and Information Engineering China University of Geosciences Auto Navi Software Co. Ltd. School of Computer Science China University of Geosciences Yantai geological survey of Coastal resources Center

This study reveals the temporal and spatial evolution characteristics of the winter nighttime urban heat island(UHI) effect in the case of beijing, China. The land surface temperature(LST) is retrieved by radiative transfer equation by using the remote sensing data from Landsat ETM+/OLI＿TIRS from 2007 to 2017 for the winter nighttime period, and LST is then divided by the mean-standard deviation method into different levels of thermal landscapes. A combination of the migration calculation of gravity center and multi-directional profile analysis is used to study the directional differentiation characteristics of LST and the migratory characteristics of the gravity center of UHI. Finally, the overall temporal and spatial evolution characteristics of winter nighttime surface urban heat island(SUHI) in beijing are studied, and the possible reasons for the changes are discussed. Results show that beijing ' s UHI effect first increased and subsequently decreased from 2007 to 2017. The winter heat island in the urban area developed from low-density agglomeration to high-density agglomeration to lowdensity diffusion. Additionally, the high-level thermal landscapes migrated to the {3.west along with the city center of gravity, and the expansion rate is fastest in the {3.west, which is directly linked to the changes in the urban construction land. Moreover, the overall spatial distribution of winter nighttime LST is high in the east and {3. and low in the west and north, and is influenced by topography, land cover, urbanization, anthropogenic heat, and other factors as well.

关键词： land surface temperature urban heat island spatio-temporal characteristics winter environmentgeology

LA-ICP-MS zircon U-Pb dating of tuffites in the Sachakou Pb-Zn mining area, Karakorum, Xinjiang and its establishment of Early Triassic strata

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China geology 2024年第1期7卷 150-152页

作者： Xiao-jian Zhao Nuo Li Kai Weng Ming Wang Qing-lin Sui Deng-hui Chen Zhou-ping guo Meng-qi Jin Xi’an Center China Geological SurveyMinistry of Natural ResourcesXi’an 710054China Xinjiang Research Center for mineral resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China College of Geography and Remote Sensing sciences Xinjiang UniversityUrumqi 830046China University of chinese academy of sciences Beijing 100029China No.8 geological party Xinjiang Bureau of Geology and Mineral Exploration and DevelopmentAksu 843000China School of Resource&Environment and Safety Engineering University of South ChinaHengyang 421001China

*** In the past decade,a group of medium to giant lead-zinc deposits,represented by Huoshaoyun,Sachakou,and Yuanbaoling,have been discovered in the Aksai Chin region of Karakoram,*** are all located in the Mesozoic carbonate and clastic rock *** Sachakou leadzinc mining area is adjacent to the northwest of the Huoshaoyun lead-zinc mining area and is in the same stratigraphic layer as *** many scholars have been arguing about the type and age of Huoshaoyun lead-zinc mineralization,few scholars have paid attention to the classification of the ore-bearing strata in the *** stratigraphy of the Lower Permian Shenxianwan Group to the Upper Cretaceous Tielongtan Group is exposed in the Sachakou area of Karakorum,Xinjiang,however,the Late Permian-Early Triassic stratigraphy is missing(Fig.1a).Due to the harsh natural conditions in the area and the low level of work,the stratigraphic delineation is not exhaustive,and the regional lithology is dominated by carbonates and clastic rocks,which makes it difficult to identify the age of the regional lithology and causes problems for the exploration and research of lead-zinc in the area.

关键词： strata Triassic Xinjiang

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印支造山带:Song Chay构造带

岩石学报 2024年第1期40卷 1-28页

作者：林伟王印刘飞孟令通吴钦颖郭钊李金雁岩石圈演化国家重点实验室中国科学院地质与地球物理研究所中国科学院地球科学研究院北京100029 中国科学院大学地球与行星科学学院北京100049 中石化经纬有限公司地质技术测控技术研究院青岛266071 中国地质调查局武汉地质调查中心武汉430205

印支运动是二十世纪初法国地质学家根据越南北部晚三叠世大规模角度不整合所提出。越南北部的Song Chay构造带作为印支造山带概念的提出地,记录了大量经典的印支造山相关的信息,是理解印支造山带构造演化的关键地区。本文在课题组对Song... 详细信息

印支运动是二十世纪初法国地质学家根据越南北部晚三叠世大规模角度不整合所提出。越南北部的Song Chay构造带作为印支造山带概念的提出地,记录了大量经典的印支造山相关的信息,是理解印支造山带构造演化的关键地区。本文在课题组对Song Chay地区十多年研究基础上,结合前人研究成果,系统厘定了Song Chay构造带的几何空间格架、运动学特征及其演化过程。详细的野外地质考察表明,Song Chay构造带从SW向NE依次可以划分成:新生代的大象山单元、代表缝合带的Song Chay蛇绿混杂岩单元,以及越南东北部褶皱冲断系统。其中蛇绿混杂岩单元和褶皱冲断系统中发育NE-SW向矿物拉伸线理,并具有顶部向NE方向的剪切变形特征,指示了Song Chay洋壳向SW的俯冲以及向NE的逆冲过程。精确的年代学工作表明,Song Chay蛇绿混杂岩中斜长花岗岩的结晶年龄为3.6.4±2.9Ma,表明至少在早石炭世Song Chay洋就已经形成了成熟的大洋地壳。褶皱冲断带内部的低温年代学数据约束了顶部向NE的剪切变形年龄在250~245Ma之间,表明为华南和印支板块碰撞时间。另外,Song Chay蛇绿混杂岩基质中碎屑锆石物源研究表明,Song Chay蛇绿混杂岩基质中碎屑锆石主要是来自于俯冲的华南板块,只有很少一部分来自印支板块,因此推测Song Chay洋可能为一个十分有限的小洋盆。构造几何学、运动学以及碎屑锆石物源研究表明,在Song Chay构造带内的“滇-琼缝合带”两侧构造特征可对比,并未因“滇琼洋”的闭合而造成差异。因此,我们认为“滇-琼缝合带”并不能代表一个大洋。根据我们及前人的构造学、岩石学、年代学工作,建立了一个初步的Song Chay洋从晚石炭世至中三叠世的构造演化模型:(1)3.0~270Ma,Song Chay洋开始向SW俯冲到印支板块之下,此时岩浆弧并不发育,蛇绿混杂岩物源主要为华南板块;(2)270~250Ma,Song Chay洋继续俯冲,此时弧岩浆岩大量发育,蛇绿混杂岩同时接受弧岩浆岩及华南板块碎屑物质;(3.250~245Ma,Song Chay洋闭合,华南板块与印支板块碰撞;(4)245~23.Ma,印支造山带进入碰撞后伸展阶段。

关键词：印支运动 Song Chay构造带构造解析碎屑锆石滇-琼缝合带

Permian-Triassic magmatic evolution of granitoids from the southeastern Central Asian Orogenic Belt:Implications for accretion leading to collision

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Science China Earth sciences 2021年第5期64卷 788-806页

作者： Didi WU Shan LI David CHEW Tieyi LIU Donghai guo Key Laboratory of Deep-Earth Dynamics of Ministry of Natural resources Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Department of geology School of Natural SciencesTrinity College DublinDublin 2Ireland

Many orogenic belts in the world exhibit accretionary and collisional orogenic phases to varying *** accretion evolves into collision of the Central Asian Orogenic Belt(CAOB),the largest Phanerozoic accretionary orogenic belt,is an intriguing *** this paper,we present new U-Pb age,geochemical and isotopic data for Permian-Triassic granitoids from middle Inner Mongolia,Northern China in the southeastern CAOB,and delineate the magmatic transition from subduction to(soft)*** magmatic record of soft collision is identified and characterized by thickened lower crust-derived high Sr/Y granitoids with a sub-linear distribution along the Solonker suture *** from Early Permian to Late Permian became more enriched in whole-rock Nd and zircon Hf isotopic compositions(εNd(t)values from 2.4 to-19.5,εHf(t)values from 11.6 to-3..7),indicating increasing incorporation of old *** change in peak timing of magmatism from west(ca.264 Ma)to east(ca.251 Ma)along the Solonker suture zone implies"scissor-like"closure of the Paleo-Asian *** with previous studies,a three-stage tectonic model from the Permian to Triassic by accretion leading to collision on the south-eastern margin of CAOB is proposed.(1)Early Permian(>ca.285 Ma):Juvenile magmatism on an active continental margin with double-sided subduction of the Paleo-Asian Ocean;(2)Middle Permian to Middle Triassic(ca.285–23. Ma):Magma source transition from juvenile to old crust induced by a tectonic switch from arc to"scissor-like"closure and subsequent intracontinental orogenic contraction;(3.Late Triassic(3. Ma):A-type and alkaline magmatism in response to post-collisional extension.

关键词： Central Asian Orogenic Belt(CAOB) Accretionary orogeny Tectono-magmatic evolution Soft collision

Neoproterozoic–Early Paleozoic Tectonic Evolution of the south China Craton： New Insights from the Polyphase Deformation in the southwestern Jiangnan Orogen

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1700-1727页

作者： ZHAO Zhongbao XU Zhiqin MA Xuxuan LIANG Fenghua guo Peng Key Laboratory of Deep-Earth Dynamics of Ministry of Natural resources China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory for mineral deposits Research Department of Earth Sciences Nanjing University Nanjing 210046 China School of Earth Science and resources China University of Geosciences Beijing 100083 China

A 〉1500–km–long northeast–southwest trending Neoproterozoic metamorphic belt in the south China Craton（SCC） consists of subduction mélange and extensional basin deposits. This belt is present under an unconformity of Devonian–Carboniferous sediments. Tectonic evolution of the Neoproterozoic rocks is crucial to determining the {3. of the SCC and further influences the reconstruction of the Rodinia supercontinent. A subduction mélange unit enclosed ca.1000–850–Ma mafic blocks, which defined a Neoproterozoic ocean that existed within the SCC, is exposed at the bottom of the Jiangnan Orogen（JO） and experienced at least two phases deformation. Combined with new（detrital） zircon U–Pb ages from metasandstones, as well as igneous rocks within the metamorphic belt, we restrict the strongly deformed subduction mélange as younger than the minimum detrital age ca. 83. Ma and older than the ca. 815 Ma intruded granite. Unconformably overlying the subduction mélange and the intruded granite, an intra–continental rift basin developed 〈800 Ma that involved abundant mantle inputs, such as mafic dikes. This stratum only experienced one main phase deformation. According to our white mica ^40Ar/^（3.）Ar data and previously documented thermochronology, both the Neoproterozoic mélange and younger strata were exhumed by a 490–400–Ma crustal–scale positive flower structure. This orogenic event probably induced the thick–skinned structures and was accompanied by crustal thickening, metamorphism and magmatism and led to the closure of the pre–existing rift basin. Integrating previously published data and our new results, we agree that the SCC was located on the periphery of the Rodinia supercontinent from the Neoproterozic until the Ordovician. Furthermore, we prefer that the convergence and dispersal of the SCC were primarily controlled by oceanic subduction forces that occurred within or periphery of the SCC.

关键词： Rodinia supercontinent south China Craton Jiangnan Orogen intra–continental rifting intra–continental orogen

Petrogenesis and Tectonic Significance of Carboniferous Granites on the North Side of the Solonker Suture,Central south Mongolia

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 481-499页

作者： ZHANG Xiaowei TONG Ying WANG Tao ZHAO Hui guo Lei Narantsetseg TSERENDASH Delgerzaya UNTSAG institute of geology Chinese Academy of Geological SciencesBeijing 100037China Key Laboratory of Deep-Earth Dynamics of Ministry of Natural resources Beijing 100037China Chifeng University ChifengInner Mongolia 024000China institute of Paleontology and geology Mongolian Academy of SciencesUlaanbaatar 15160Mongolia

The central part of south Mongolia,located to the north of the Solonker Suture,is a key region for studying the late Paleozoic tectonic evolution of the Central Asian Orogenic Belt(CAOB).Voluminous late Paleozoic granitic rocks,especially of Carboniferous age,were intruded in this ***,these granitoids have not been well studied and there is a lack of precise ages and isotopic *** has hampered our understanding of the tectonic evolution of southeastern Mongolia,and even the entire *** this paper,we provide new U-Pb isotopic ages and geochemical analyses for these Carboniferous *** granite from the Ulaanbadrakh pluton yielded a zircon U-Pb age of 3.6 Ma,which indicates emplacement in the Early Carboniferous,and three other granites from the Khatanbulag region gave zircon U-Pb ages of 3.6 Ma,3.5 Ma,and 3.1 Ma,which indicate emplacement in the Late *** Early Carboniferous granite has SiO2 contents of 70.04–70.3. wt%and K_(2)O+Na_(2)O contents of 6.48–6.63.wt%,whereas the Late Carboniferous granites have more variable compositions(SiO2=65.29–77.91 wt%and K2O+Na2O=5.3.–7.27 wt%).All the granites are weakly-peraluminous I-types that are relatively enriched in U,Th,K,Zr,Hf,and *** whole rock Sr-Nd and zircon in situ Lu-Hf isotope analyses for the Early Carboniferous granite gave positive values ofεNd(t)(2.87)andεHf(t)(4.3.–12.3.)with young Nd(TDM=860 Ma)and Hf(TDMc=13.7–63. Ma)two-stage model ages,indicating derivation from juvenile crustal *** contrast,the Late Carboniferous granites had more diverse values ofεNd(t)(–4.03.to 2.18)andεHf(t)(–12.69 to 5.04)with old Nd(TDM=13.8–1225 Ma)and Hf(TDMc=2881–1294 Ma)depleted mantle two-stage model ages,suggesting derivation from remelting of Precambrian *** on the existing results,the tectonic setting of the Late Carboniferous granites in the central part of south Mongolia is known for its diversity,and this paper believes that the tectonic background of the carboni

关键词： Carboniferous granites continental margin arc post-collisional central south Mongolia Central Asian Orogenic Belt

Stretching characteristics and its dynamic significance of the northern continental margin of south China Sea

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Science China Earth sciences 2008年第3期51卷 422-430页

作者： ZHANG YunFan SUN Zhen ZHOU Di guo XingWei SHI XiaoBin WU XiangJie PANG Xiong CAS Key Laboratory of Marginal Sea geology South China Sea Institute of OceanologyChinese Academy of SciencesGuang-zhou 510301China Graduate University Chinese Academy of SciencesBeijing 100049China Qingdao institute of Marine geology China Geological SurveyQingdao 266071China China National Offshore Oil Corp.China Limited Shenzhen Guangzhou 510240China

To investigate the thinning of the whole crust, and the contribution of the upper versus lower crust to the stretching since Cenozoic, we calculated the stretching factor of the northern margin of south China Sea with data such as whole crustal thickness, depth of Cenozoic sedimentary basement and the horizontal displacement of faults. An isometric line drawing on whole crustal stretching factor is then obtained. Along the seismic Line 153. in Baiyun sag, we also calculated the stretching factors of the upper and lower crust. The results suggest that the whole crustal thickness decreases seaward while the whole crustal stretching factor increases from shelf to slope. The Moho upwells highest beneath where the crust is thinned most. The value of the whole crustal stretching factor ranges from 1.5 to 6. Two areas were thinned intensely: the center of Yinggehai Basin, and the Baiyun sag in the Pearl River Mouth Basin. The calculation of the upper and lower crustal stretching factors from DSP153. in Baiyun sag shows that the original crust of Baiyun sag should be thinned before deformation. Its pre-Cenozoic evolution as well as tectonic position during Cenozoic might be responsible for that.

关键词： stretching factor the northern continental margin of south China Sea upper crust lower crust original hot thinned crust Baiyun sag

小兴安岭南段翠峦杂岩体成因及构造环境:来自地球化学及锆石Hf同位素的证据

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地质通报 2024年第2期43卷 416-428页

作者：杨元江张立东杨文鹏李成禄郭凤磊赵寒冬邓昌州沈龙申亮黑龙江省自然资源调查院黑龙江哈尔滨150036 黑龙江省第一地质勘查院黑龙江牡丹江157011 中国科学院地球化学研究所贵州贵阳550081 中国地质调查局发展研究中心北京100037

通过对黑龙江省小兴安岭南段中奥陶世翠峦杂岩体的年代学、岩石地球化学、锆石Hf同位素特征的研究,探讨岩体的形成时代、成因、物质来源和构造背景。采用LA-ICP-MS锆石U-Pb定年,获得花岗闪长岩和二长花岗岩样品的年龄分别为463.2 Ma和... 详细信息

通过对黑龙江省小兴安岭南段中奥陶世翠峦杂岩体的年代学、岩石地球化学、锆石Hf同位素特征的研究,探讨岩体的形成时代、成因、物质来源和构造背景。采用LA-ICP-MS锆石U-Pb定年,获得花岗闪长岩和二长花岗岩样品的年龄分别为463.2 Ma和462±2 Ma,时代为中奥陶世。全岩地球化学研究表明,岩石均具有高Si、高K富碱,贫Ti、Mg、Fe、P等特征。大离子亲石元素K、Rb富集,高场强元素Ti、Nb、Ta、P和HREE亏损,具有显著的负Eu异常(δEu=0.3.~0.64),以上都显示岩浆的壳源特征。花岗闪长岩锆石的εHf(t)=2.4~3.4,数值集中且均分布于球粒陨石线之上,暗示岩浆源区为新生陆壳物质的部分熔融;地壳模式年龄TDM c=1070~1128 Ma,证实该地区存在中元古代地壳增生事件。本次研究认为,翠峦杂岩体形成于洋陆板块俯冲的构造环境。

关键词：杂岩体锆石U-Pb年龄锆石Hf同位素岩石成因小兴安岭南段