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Science China Earth sciences 2024年第4期67卷 1152-1194页

作者： Guichun wu Zhansheng JI Gary GLASH Qinggao ZENG Jianxin YAO Key Laboratory of Stratigraphy and Palaeontology Ministry of Natural ResourcesInstitute of GeologyChinese Academy of Geological SciencesBeijing 100037China SinoProbe Laboratory Chinese Academy of Geological SciencesBeijing 100094China Department of geology and Environmental sciences State University of New York-FredoniaFredoniaNY 14063USA Xizang Autonomous Region Geological and Mineral Exploration and Development Burea Lhasa 850010China

Rocks of the Qinghai-Tibetan Plateau(QTP)host abundant Triassic *** far,the well established marine fossil sequences based on ammonoids,conodonts,bivalves,brachiopods,radiolarians,and terrestrial spora-pollen sequence have become standard for biostratigraphic correlation of the *** much of Triassic time,the QTP occupied a marine setting as suggested by the dominance of marine *** main sedimentary types represented in the Triassic successions include littoral to shallow marine clastic rocks,shallow marine carbonate platform carbonates,bathyal to abyssal slope carbonates intercalated with clastic and siliceous deposits,coal-bearing clastic strata contained within paralic facies deposits,and littoral and terrestrial volcaniclastic *** deposits are organized into four stages in ascending order:(1)Early Triassic deposits that record marine transgression,including extensive shallow marine carbonate platform strata.(2)Middle Triassic Ladinian to Late Triassic Carnian deposits,including thin-bedded limestone,fine clastics,and siliceous rocks,that accumulated at greater depths than underlying Early Triassic strata and reflect the peak of the *** activity appears to have occurred in some areas during this stage.(3.Late Triassic Norian deposits that record the onset of marine regression as suggested by the widespread occurrence of platform *** is noteworthy that stage 3.deposits of the Qin-Qi-Kun area in the northernmost region of the QPT is dominated by terrestrial strata and displays evidence of local erosion.(4)Late Triassic Rhaetian littoral and shallow marine clastic and coal-bearing deposits that preserve the record of continued marine regression *** Indus-Yarlungzangbo Suture Zone(IYSZ)appears to have been the rifting axis during Triassic time as suggested by sedimentary facies trends that reflect deepening to south and ***,the Himalaya Block to the south of the IYSZ was part of the passive margin

关键词： Qinghai-Tibetan Plateau Triassic Biostratigraphy Lithostratigraphy Palaeobiogeography Sedimentary palaeogeography

Distribution and identification of the low-velocity layer in the northern South China Sea

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Progress in Natural Science:Materials International 2007年第5期17卷 591-600页

作者： Zhao Minghui, Qiu Xuelin, Xu Huilong, Shi Xiaobin, wu Shimin , Ye Chunming and Xia Shaohong (Key Laboratory of Marginal Sea geology, South China Sea institute of Oceanology,{3., Guangzhou 5103.1, China Earthquake Administration of Guangdong Province, Guangzhou 510070, China) Key Laboratory of Marginal Sea geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Earthquake Administration of Guangdong Province Guangzhou 510070 China

The low-velocity layer (LVL), closely related with tectonic activities and dynamic settings, has always been a hot topic in the deep crustal structure studies. The deep seismic (OBS/OBH) and onshore-offshore experiments have been extensively implemented in the northern South China Sea (SCS) since the 1990s. Six seismic profiles were finished on the northern margin of SCS by domestic and international cooperations. The features of crustal structures were revealed and five velocity-inversion layers were discovered. Among them three LVLs with 3.0—3. 5 km·s-1 velocity are located in the sedimentary structure (2.0—6.0 km in depth and 2.0—4. 6 km in thickness) of the Yinggehai Basin and Pearl River Mouth Basin. They were identified by the reflective and refractive phases for their shallow depth. The other two LVLs with 5.5—6.0 km·s-1 velocity generally existed in the middle crust (7.0—18.0 km in depth) with an about 2.5—6.0 km thickness in the transitional crustal structure of the northeastern and northwestern SCS. They were detected by the refractive phase from their overlain and underlying layers. We explored the possible tectonic formation mechanisms combining with previously reported results, which provided evidence for the formation and evolution of SCS.

关键词： low-velocity layer deep crustal structure the northern South China Sea OBS/OBH and onshore-offshore seismic experiments.

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 157–13. 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

THRUST TECTONICS AND RELATED CROSS-SECTION BALANCING IN THE SOUTHWESTERN FUJIAN FORELAND FOLD AND THRUST BELT

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Scientia Geologica Sinica 2000年第2期 151-158页

作者： wu Yungao and Li Jiliang (Laboratory of Lithosphere Tectonic Evolution, institute of geology and {3. chinese academy of sciences, Beijing 100029) Lu Huafu and Jia dong (Department of Geosciences, University of Nanjing Nanjing 210093.

On the basis of the data made by former geological researchers and our own studies, the thrust and nappe tectonics, widely found in the Mesozoic Southwestern Fujianforeland fold and thrust belt, can be classified into two types :①cover thrust sheets, ②basement thrust sheets, also called C-type thrust sheets (i.e. Composite thrust sheets). The main structural styles developed in the this belt include stepped thrust fault and fault-related fold such as fault-bend fold, imbricate fan and duplex, klippe and window,and back thrust. The main thrust direction was from SE to NW. Two typical balanced cross-sections and their restored ones are presented in the paper. The authors think that the mie shortened distance of the Southwestern Fujianforeland fold and thrust belt is between 47.7km and 170km, and the true shortened rate is between 25% and 54%.

关键词： In THRUST TECTONICS AND RELATED CROSS-SECTION BALANCING IN THE SOUTHWESTERN FUJIAN FORELAND FOLD AND THRUST BELT AL

THE ALTUN—NORTH QAIDAM ECLOGITE BELT IN WESTERN CHINA—ANOTHER HP-UHP METAMORPHIC BELT TRUNCATED BY LARGE SCALE STRIKE-SLIP FAULT IN CHINA

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地学前缘 2000年第S1期7卷 254-255页

作者： Zhang Jianxin, Xu Zhiqin, Yang Jingsui, Li Haibing, wu Cailai(institute of geology, {3. {3. of Geological sciences, 26 Baiwanzhuang, Beijing 10003.,China, E\|mail: zjx66@***)

The Altun and North Qaidam Mountains at the northern margin of Qinghai\|Tibet plateau are separated by the Altyn Tagh sinistral strike\|slip fault, which is one of the largest strike\|slip fault systems in the world and was considered as the key element in the escape tectonics model for Euraisa\|India continent\|continent ***,the eclogites within quratzifeldspathic gneisses or pelitic gneisses characterized by amphibolite\|facies paragenesis were discovered in the Altun and the North Qaidam Mountains(Fig.1). They occur as lens or boundins within the Altun Group and Dakendaban Group respectively which previously were considered as metamorphic basement of Tarim block and Qaidam block. Our studies indicate that the eclogites outcrop in both the Altun and North Qaidam Mountains show similar occurrences, associated country rocks, rock and mineral assemblages, p\|T\% estimates, geochemistryand protolith feature and ages of peak metamorphism (see table) . The garnet\|omphacite\|phengite geothermobarometer gave equilibrium condition of \%p\%=2 8～3.0GPa and t =820～850℃ for the Altun eclogite and p =2 8GPa and \%t\%=73.℃ for North Qaidam eclogite respectively(Fig..2). These p\|T conditions are in the coesite stability field. Moreover, Po lycrystalline quartz pseudomorphs after coesite have been identified in the Dulan area, North Qaidam Mountains (Song et al, in review). Therefore, these features suggest that both eclogites of Altun and North Qaidam Mountains probably are a same HP\|UHP metamorphic belt formed from the same of Early Paleozoic age deep subduction and collision, and subsequently displaced by the Altyn Tagh *** case is similar to the Dabie\|Sulu HP\|UHP metamorphic zone which was truncated by the Tanlu sinistral strike\|slip fault and splitted it into two distincts, the Dabie region and Sulu region. These correlations support an about 3.0～400km displacement of the Altyn Tagh sinistral strike\|slip fault (Fig.1).

关键词： Altun mountains North Qaidam Mountains HP\|UHP metamorphic b elt Altyn Tagh fault

Palinspastic reconstruction and geological evolution of Jurassic basins in Mongolia and neighboring China

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Journal of Palaeogeography 2013年第3期2卷 306-317页

作者： wu genyao institute of geology and geophysics Chinese Academy of Sciences

The important event in Jurassic tectonics in Mongolia was the subduction and closure of the Mongolia-Okhotsk ocean;correspondingly,basin evolution can be divided into two main stages,related to the orogeny and collapse of the orogenic belt,*** developing of Early-Middle Jurassic basins to the north of the ocean resulted from back-arc *** fossil sutures,from the China-SE Asia sub-continent to the south of the ocean,were rejuvenated by subduction-related orogeny;in addition,the Yanshanian intra-continental movement *** Early-Middle Jurassic molasse basins were developed by movement in Inner Mongolia,all of which stretched westwards (or northwards) into Mongolia;therefore,the molasse basins in eastern and southern Mongolia had the same geometric and kinematic features as the basins in the Inner *** to the collapse of the MongoliaOkhotsk orogenic belt,a group of rift basins developed during the Late *** eastern Mongolia,the NE orientated extensional basins were controlled by the neogenic *** contemporary basins in southern Mongolia and the neighboring areas in China were constrained by remobilization (inherited activation) of the latitudinal or ENE-directional basement *** stages can be recognized in the evolution of the Early-Middle Jurassic basins after reversal;the basins also experienced four episodes of reformation.

关键词： back-arc extension molasse basin collapse rift basin evolution basement structure neogenic structure Jurassic Mongolia and neighboring China

Beamlet migration for complex structure and local angle-domain analysis

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Beamlet migration for complex structure and local angle-doma...

Effects of single face slope on seismic ground responses

CPS/SEG 2004 International Geophysical Conference

作者： wu Rushan Modeling and imaging laboratory institute of geophysics and planetary University of California Santa Cruz CA 95064 Luo Mingqiu Chen Ling Presently at institute of {3. and geophysics chinese academy of sciences Beijing China 100101

＜正＞ Beamlet prestack migration is implemented in the shot domain. Both the source field and the receiver array field are decomposed into LCB beamlets and sinked down to image levels using beamlet propagators. Imaging condition can be applied either in beamlet domain or space domain. As an example, the 45 shots synthetic data of SEG/EAGE salt model are used for imaging. The results demonstrate the high resolution and high quality feature of the beamlet migration, that can be seen clearly from the images of the highly irregular top salt boundary. A method of local AVA （amplitude versus angle） analysis during the process of prestack depth migration in angle domain is proposed based on the local image matrix obtained through beamlet decomposition （wavelet transform along spatial axis） of both the incident and scattered wave field at the image locality. The local image matrices can be reduced to common refection-angle image （CRAI） gathers and common dip-angle image （CDAI） gathers. CDAI gathers can be used to determine the dip-angle of the reflector and CRAI gathers are then used for local AVA analysis. Preliminary numerical tests demonstrate the feasibility of the method.

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Effects of single face slope on seismic ground responses

Carboniferous Biostratigraphy of Guizhou Province

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Shengwen Qi & Faquan wu institute of geology and {3.,chinese academy of sciences,China Chunling Liu Aero-geophysical Survey and Remote Sensing Center,The Ministry of Land and Resource,China

Seismic Ground Responses are strongly determined by the surface topography. The paper presents the effects of single surface slope on seismic ground responses based on lots of numerical simulations with three dimensional fast Lagrangian analysis of continua (FLAC3.).Two types charts of peak ground acceleration(PGA)distribution are summarized for single surface slopes,typeⅠshows that PGA is amplifying with increasing of slope elevation,and typeⅡshows that PGA is amplifying first,then drawing down,and fluctuating with increasing of slope *** shows that to slopes consisting of same material, there exists a critical height between typeⅠand typeⅡ.If the height of the slope is lower than the critical height,the distribution of PGA of the slope shows type I,vice verse,the distribution of PGA shows typeⅡ.Combining the dimensional analysis method with results of lots of numerical simulation,the paper reaches a formula on critical height between two types, which indicates that the critical height is strongly dependent on the inputted *** based on lots of numerical simulations show that the critical height is about one fifth of the inputted wavelength.

关键词： Slope Seismic Amplification Peak Ground Acceleration(PGA) FLAC3.

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Acta Geologica Sinica(English Edition) 1988年第2期1卷 113-125页

作者： wu Qianghe Guizhou institute of geology, Guiyang, Guizhou Guizhou institute of geology Guiyang Guizhou

The Carboniferous in Guizhou may be divided into 3.lithostratigraphic regions, 2 series and 7 stages. TheLower Carboniferous is composed of 4 regional stages, 1 foraminifer assemblage, 4 fossil coral zones (with 9subzones) and 11 brachiopod assemblages; the Upper Carboniferous is divided into 3.regional. stages, 9fusulinid zones (with 2 subzones) and 4 ammonite zones. Based on the studies of foraminifers and *** base of the Carboniferous in Guizhou 1s placed at least near the top of the coral Cystophrentis zone.

关键词： Th Carboniferous Biostratigraphy of Guizhou Province