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Mesozoic subduction-accretion zone in northeastern South china Sea inferred from geophysical interpretations

Science china Earth Sciences 2006年第5期49卷 471-482页

作者： ZHOU Di1, WANG Wanyin2. WANG Jialin3, PANG Xiong4. CAI Dongsheng5 & SUN Zhen1 1. Key Laboratory of Marginal Sea Geology, South china Sea Institute of Oceanology, Chinese Academy of Sciences, Guang- zhou 510301, china 2. {2. of geological and {4. Engineering, chang’an university, Xi’an 710054. china 3. Key Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. china 4. china National Offshore Oil Co. Limited – Shenzhen Branch, Shenzhen 518067, china 5. china National Offshore Oil Co. Limited – Research Center, Beijing 10002., china 1. Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. college of geological and {2. Engineering Chang’an University Xi’an 710054 China 3. Key Laboratory of Marine Geology Tongji University Shanghai 200092 China 4. china National Offshore Oil Co. Limited — Shenzhen Branch Shenzhen 518067 China 5. china National Offshore Oil Co. Limited — Research Center Beijing 100027 China

A segment of Mesozoic subduction-accretion zone was inferred across thenortheastern South china Sea at approximately NE4.0 orientation. Basic evidence includes thefollowing: A belt of peek gross horizontal Bouguer gravity gradient (PGHGBA) is comparable in sizeand intensity to that of the Manila subduction-accretion zone. A belt of high positive magneticanomalies appears to the north and sub-parallel to the PGHGBA, representing the volcanic arcassociated to the subduction zone. The PGHGBA crosses obliquely both Cenozoic structures and presentseafloor topography, indicating a pre-Cenozoic age. The segment is offset left-laterally byNW-running strike-slip faults, in concord with the Mesozoic stress field of South china. Inaddition, the existence of the subduction zone is supported by wide-angle seismic data obtained indifferent years by different institutions. At approximate localities, a north-dipping ramp of Mohosurface is indicated by records of ocean-bottom seismometers, and a strong reflector about 8 kmbeneath the Moho reflector is indicated by both OBS and long-cable seismic records. Theidentification of a segment of Mesozoic subduction zone in NE South china Sea fills nicely the gapof the Great Late Mesozoic Circum SE Asia Subduction-acrretion Zone, which extended from Sumatra,Java, SE Kalimantan to N Palawan, and from Taiwan, Ryukyu to SW Japan.

关键词： Mesozoic, subduction zone, SE Asia, NE South china Sea, geophysics.

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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science china Earth Sciences 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2.3,4.SUN BaiNian 1,2.,LI XiangChuan 1,REN WenXiu 1 &JIA Hui 1 1 Key Laboratory of Western china's Environmental Systems of the Ministry of Education and college of Earth and Environment Science,Lanzhou {2.,Lanzhou 730000,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 2.0008,china 3 college of Arts and Sciences,Bryant {2.,Smithfield RI 02.17,U.S.A. 4.Key Laboratory of Western china's Mineral Resources and geological Engineering of Ministry of Education,{14.’an {2.,Xi’an 710054.china 1. Key Laboratory of Western china’s Environmental Systems of the Ministry of Education and college of Earth and Environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 4.%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

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CENOZOIC VOLCANISM AND GEOTHERMAL RESOURCES IN NORTHEAST china

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Chinese Geographical Science 2001年第2期11卷 150-154页

作者： WANG Xi-kui1, QIU Shan-wen2. SONG chang-chun2. KULAKOV Aleksey3, TASHCHI Stepan3, MYASNIKOV Evgeny3 (1.college of Earth Sciences, Jilin {2.,changchun 130012.P.R.{4. 2.changchun Institute of Geography, the Chinese Academy of Sciences,changchun college of Earth Sciences Jilin University Changchun P. R. China changchun Institute of Geography the Chinese Academy of Sciences Changchun P. R. China Pacific Institute of Geography Far East Science Center of the Russian Academy of Sciences Vladivostok Russia

This paper is concentrated on Cenozoic volcanism and geothermal resources in Northeast china. There are a lot of Cenozoic volcanoes, a large area of volcanic rocks, a large number of active faults and rich geothermal resources in Northeast china. The time and space characteristics of Cenozoic volcanism and the space distribution characters of hot springs and high geothermal flux regions in Northeast china are described and discussed on the basis of geological, geothermal, drilling and volcanological data. It is revealed that the hot springs and high geothermal flux regions are related to the Cenozoic volcanism, rifting and faulting in Northeast china. It is especially emphasized that the hot springs and high geothermal anomaly areas are controlled by active deep faults. It is proposed that the Cenozoic volcanism regions, rift basins, active fault belts, activated plate suture zones and large earthquake occurrence points are the best areas for prospecting geothermal resources. The geothermal resources in younger volcanic zones are richer than those in older volcanic belts. The hot springs and active or activated faults might be a very good clue for looking for geothermal resources.

关键词： volcanism active faults geothermal resources Northeast china

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Morphological and Sulfur-Isotopic Characteristics of Pyrites in the Deep Sediments from Xisha Trough,South china Sea

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Journal of Ocean university of china 2024年第1期23卷 138-148页

作者： chang Jingyi LIU Yujia LU Hailong LU Jing’an SU Xin YE Jianliang XIE Wenwei college of Engineering Peking UniversityBeijing 100871China Beijing International Center for Gas Hydrate School of Earth and Planetary SciencesPeking UniversityBeijing 100871China School of Marine Science Nanjing University of Information Science and TechnologyNanjing 210044China MLR Key Laboratory of Marine Mineral Resources Guangzhou Marine Geological SurveyMinistry of Land and ResourcesGuangzhou 510075China School of Ocean Sciences China University of GeosciencesBeijing 100083China

Pyrite is one of the common authigenic minerals in marine *** studies have shown that the morphological and isotopic characteristics of pyrite are closely related to the geochemical environment where it is *** better understand the for-mation mechanism of authigenic pyrite,we analyzed the isotopic composition,morphology,and distribution of pyrite in the sediment at 500m below the seafloor from Xisha Trough,South china *** morphologies were observed by scanning electron micros-copy and Raman spectrography.X-Ray computed tomography was applied to measure the particle size of *** size of pyrite crystals in the matrix sediment mainly ranged between 2. and 65µm(***.4.µm),although crystals were larger(***.50μm)in the *** pyrites had a fine-grained truncated octahedral shape with occasionally well-developed growth steps,which implies the low growth rate and weak anaerobic oxidation of methane-sulfate reduction when pyrite was ***δ^(34.S values of pyrites ranged from+2..8‰Vienna-defined Canyon Diablo Troilite(V-CDT)to+33.2.V-CDT and from+4..8‰V-CDT to+4..9‰,which suggest two growth *** the first stage,with the continuous low methane flux,the pyrite possibly formed in an environment with good access to *** the second stage,the pyrites mainly developed in sediment fractures and appeared in veins,probably due to the limited availability of *** less exposure of pyrite to the environment in the second stage was probably caused by sediment accumulation or *** this study,an episodic pyritization process was identified,and the paleoenvironment was reconstructed for the sediment investigated.

关键词： pyrite sulfur isotope AOM methane flux Xisha Trough South china Sea

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Lithological Facies Classification Using Attention-Based Gated Recurrent Unit

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Tsinghua Science and Technology 2024年第4期29卷 1206-1218页

作者： Yuwen Liu Yulan Zhang Xingyuan Mao Xucheng Zhou Jingwen chang Wenwei Wang Pan Wang Lianyong Qi college of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Shandong Provincial university Laboratory for Protected Horticulture Weifang University of Science and TechnologyShouguang 262700China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China Shandong Provincial Key Laboratory of Network Based Intelligent Computing University of JinanJinan 250022China School of Modern Posts Nanjing University of Posts and TelecommunicationsNanjing 210023China

Lithological facies classification is a pivotal task in petroleum geology, underpinning reservoir characterization and influencing decision-making in exploration and production operations. Traditional classification methods, such as support vector machines and Gaussian process classifiers, often struggle with the complexity and nonlinearity of geological data, leading to suboptimal performance. Moreover, numerous prevalent approaches fail to adequately consider the inherent dependencies in the sequence of measurements from adjacent depths in a well. A novel approach leveraging an attention-based gated recurrent unit (AGRU) model is introduced in this paper to address these challenges. The AGRU model excels by exploiting the sequential nature of well-log data and capturing long-range dependencies through an attention mechanism. This model enables a flexible and context-dependent weighting of different parts of the sequence, enhancing the discernment of key features for classification. The proposed method was validated on two publicly available datasets. Results demonstrate a considerably improvement over traditional methods. Specifically, the AGRU model achieved superior performance metrics considering precision, recall, and F1-score.

关键词： attention mechanism facies classification GRU MLP(multilayer perceptron)

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南峪水电站工程地质灾害危险性评估

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水电能源科学 2010年第11期28卷 67-69,172页

作者：穆鹏武警工程学院陕西西安710086 长安大学西部矿产资源与地质工程教育部重点实验室陕西西安710054

以南峪水电站为例,基于工程区内各类地质灾害调查资料,对地质灾害危险性的现状进行了评估和预测,并综合分析了地质灾害危害程度,根据不同灾种提出相应的防治措施,为工程建设防治地质灾害提供了科学依据。

关键词：水电站建设用地地质灾害危险性评估防治措施

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Late Mesozoic Exhumation of the Huangling Massif:Constraints on the Evolution of the Middle Yangtze River

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 250-264页

作者： SU Jianchao LIN Xu LI chang’an Jolivet MARC WU Lin CHENG Feng DENG Bin WU Zhonghai CHEN Xiaokang HU Chengwei School of Geography and Information Engineering China University of GeosciencesWuhan 430074China college of Civil Engineering and Architecture China Three Gorges UniversityYichangHubei 443002China Géosciences Rennes CNRS-UMR6118Univ RennesRennesFrance State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBejing 100029China Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing 100871China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation/Chengdu university of Technology Chengdu 100871China Institute of geological Mechanics Chinese Academy of Geological ScienceBeijing 100081China

Plate subduction leads to complex exhumation processes on *** Huangling Massif lies at the northern margin of the South china *** the Huangling Massif was exhumed as a watershed of the middle reaches of the Paleo-Yangtze River during the Mesozoic remains under *** examined the exhumation history of the Huangling Massif based on six granite bedrock samples,using apatite fission track(AFT)and apatite and zircon(U-Th)/He(AHe and ZHe)*** samples yielded ages of 157–132.Ma(ZHe),119–106 Ma(AFT),and 114.72.Ma(AHe),*** modeling revealed that three phases of rapid cooling occurred during the Late Jurassic–Early Cretaceous,late Early Cretaceous,and Late *** exhumation processes led to the high topographic relief responsible for the emergence of the Huangling *** integrated of our new data with published sedimentological records suggests that the Huangling Massif might have been the watershed of the middle reaches of the Paleo-Yangtze River since the *** that time,the rivers flowed westward into the Sichuan Basin and eastward into the Jianghan *** subduction of the Pacific Plate beneath the Asian continent in the Mesozoic deeply influenced the geomorphic evolution of the South china Block.

关键词： apatite zircon (U-Th)/He fission track Huangling Massif Yangtze River

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New material of Coniopteris simplex from the Middle Jurassic of the Ordos Basin,Inner Mongolia,china and implications on its spatio-temporal distribution and paleogeography

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Journal of Palaeogeography 2024年第2期13卷 199-211页

作者： Yun-Feng Li chang-Lu Zhang Fei Liang Xiao Tan Fan-Hao Gong Chun-Lin Sun Tao Li Yu-Ling Na Research Center of Paleontology and Stratigraphy Jilin UniversityChangchun 130026Jilin ProvinceChina college of Earth Sciences Jilin UniversityChangchun 130061Jilin ProvinceChina college of Paleontology Shenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Key Lab of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang Normal UniversityShenyang 110034Liaoning ProvinceChina Shenyang Center of geological Survey China Geological SurveyShenyang 110034Liaoning ProvinceChina

Coniopteris simplex is a common component in many Jurassic ***,due to morphological variations in sterile fronds and incomplete preservation of reproductive organs,its classification has been controversial for a long ***,we present new material collected from the Middle Jurassic Yan’an Formation in the Ordos Basin,Inner *** new material reveals important morphological characters,including hemi-dimorphic fronds,two forms of sterile pinnae,short-stalked sori and sporangia on fertile fronds,annulus of sporangium composed of about 30 cells,in situ rounded triangular spores with protruded suture,and the lips of trilete laesura encircled by one or two rows of small *** on these observations,we emended the diagnosis of this common *** spatio-temporal distribution of Coniopteris simplex shows that the iconic species was restricted to the paleolatitudes ranging from 19.5°N to 4..9°N in the Northern Hemisphere during the Early—Late Jurassic,mainly distributed in the tropical to paratropical zones,and the paleolongitude ranging from 9.6°E to 12..3°E,which may be limited by the opening of the Viking Corridor and the splitting of the Central Atlantic Ocean.

关键词： Coniopteris simplex Yan'an Formation Middle Jurassic Inner Mongolia Paleogeography

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Study and Establishment of regional elastic block strain model based on GPS data

Study and Establishment of regional elastic block strain mod...

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第三届中国卫星导航学术年会

作者： Wei QU 1,2.Qin ZHANG 1,2.Shuang-Cheng ZHANG 1,2.Li WANG 1,2.QinLiang WANG 3,Zhen-Hong LI 4..{4. of Geology Engineering and Geomatics,chang''an {2.,Xi''an 710054.china 2.Key Laboratory of Western{4.''s Mineral Resources and geological Engineering,Ministry of Education,Xi''an 710054.china 3.Second Monitoring and Application Center,Xi''an 710054.china 4.Department of Geographical and Earth Sciences,{2. of Glasgow 8QQ,UK

This paper mainly studies how to use the measured GPS data to build a rational regional crustal elastic block strain model,and chooses Xi’an as the research *** on the GPS monitoring data from 2.06 to 2.08,and by further made significant hypothesis test whether the parameters of the model can reflect the regional internal deformation characteristics,the rational regional crustal elastic block strain model of Xi’an areas is built combined with the special tectonic *** to the abovementioned,the present crustal tectonic strain parameters and its accuracy indicators of Xi’an areas are *** it is also revealed that the present strain field characteristics of Xi’an *** results show that the present tectonic strain fields have obvious differences between Xian southern and northern *** present tectonic strain fields of Xi’an southern part mainly demonstrates tensile strain with NNW-SSE direction,with the maximum value of the tensile strain reached 3.2.×10-7 /y,while the present tectonic strain fields of Xi’an northern part mainly demonstrates compression strain with NNW-SSE direction,with the maximum value of the tensile strain reached 3.07×10-7 /*** strain characteristic is corresponding to the imbalance distribution of ground fissures between Xian southern and northern areas.

关键词： GPS Elastic block strain model Tectonic strain fields Hypothesis testing

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Extensive identification of landslide boundaries using remote sensing images and deep learning method

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china Geology 2024年第2期7卷 277-290页

作者： chang-dong Li Peng-fei Feng Xi-hui Jiang Shuang Zhang Jie Meng Bing-chen Li Faculty of Engineering China University of GeoscienceWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China School of Mechanical Engineering and Electronic Information China University of GeosciencesWuhan 430074China college of Geology Engineering and Geomatics Chang’an UniversityXi’an 710054China

The frequent occurrence of extreme weather events has rendered numerous landslides to a global natural disaster *** is crucial to rapidly and accurately determine the boundaries of landslides for geohazards evaluation and emergency ***,the Skip Connection DeepLab neural network(SCDnn),a deep learning model based on 770 optical remote sensing images of landslide,is proposed to improve the accuracy of landslide boundary *** SCDnn model is optimized for the over-segmentation issue which occurs in conventional deep learning models when there is a significant degree of similarity between topographical geomorphic *** exhibits notable improvements in landslide feature extraction and semantic segmentation by combining an enhanced Atrous Spatial Pyramid Convolutional Block(ASPC)with a coding structure that reduces model *** experimental results demonstrate that SCDnn can identify landslide boundaries in 119 images with MIoU values between 0.8and 0.9;while 52.images with MIoU values exceeding 0.9,which exceeds the identification accuracy of existing *** work can offer a novel technique for the automatic extensive identification of landslide boundaries in remote sensing images in addition to establishing the groundwork for future inve stigations and applications in related domains.

关键词： Geohazard Landslide boundary detection Remote sensing image Deep learning model Steep slope Large annual rainfall Human settlements Infrastructure Agricultural land Eastern Tibetan Plateau geological hazards survey engineering

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