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Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： FU Mingzuo~(1,2.3), LI Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental geology, First institute of Oceanography. State Oceanic Administration, Qingdao 2.6061. China 2. institute of Oceanology, chinese academy of sciences, Qingdao 2.6071. China 3. Graduate School, chinese academy of sciences, Beijing 100039. China 1. Key Laboratory of Marine Sedimentology and Environmental geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14. datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2. eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4. the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14.代测定底基压型数据更新世沉积环境大西洋

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Chronological record of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) Zhang Hongfu~2.Liu Xiaoming~3 Li Zhitong~4.(1.School of Earth and Space sciences,Peking University,Beijing 100871,China 2.{4. of {2. and geophysics and Key Laboratory of Mineral Resources,{4. academy of sciences,Beijing 10002.,China 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,China 4.{4. of {2. and Mineral Resources of Shenyang,Shenyang 110032.China) [a]School of Earth and Space sciences Peking University Beijing China [b]Laboratory of Mineral Resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of geology and Mineral Resources of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4.Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North China Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

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Cosmogenic ^(2.)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science China Earth sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2.DING Lin2.LAI QingZhou2.& HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of {4. and {2.,chinese {4. of sciences,Beijing 10002.,China 2.Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,chinese {4. of sciences,Beijing 100085,China 3 institute of Mineral Resources Research,China Metallurgical {4. Bureau,Beijing 10002.,China 1. Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China2. Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing 100025 China

Various sources of 2.Ne and 2.Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in China,of cosmogenic 2.Ne and 2.Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 2.Ne and ***-heating experiments show that concen-trations of cosmogenic 2.Ne and 2.Ne in summit bedrock samples R92.2.and R92.3 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.2.±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2.0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 2.Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

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The crystal structure of (Fe_(4.Cr_(4.Ni)_(9)C_(4.

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Science China Earth sciences 2005年第3期48卷 338-345页

作者： SHI Nicheng1, MA Zhesheng1, XIONG Ming1, DAI Mingquan1, BAI Wenji2. FANG Qingsong2. YAN Binggang2.& YANG Jingsui2.1. X-ray Diffraction Laboratory, China University of Geo{4., Beijing 100083, China 2. institute of {2., chinese {4. of Geological {4., Beijing 100037, China 1. X-ray Diffraction Laboratory China University of Geosciences 100083 Beijing China 2. institute of geology Chinese Academy of Geological Sciences 100037 Beijing China

(Fe4.r4.i)9C4.is a metal carbide mineral formed by combination of Fe, Cr and Ni with C. It occurs in a chromite deposit in the Luobusha ophiolite, Tibet. Based on the determina- tion of its crystal structure, the empirical formula is (Fe4.12.r3.84.i0.96)8.92.3.70 and the simplified formula is (Fe4.r4.i)4.9. The mineral is hexagonal with a = 1.38392.2. nm, c = 0.4.690(9) nm, space group P63 m c, Z=6 and the calculated specific gravity Dx = 7.089 g/cm3. Fe, Cr and Ni occupy different crystallographic sites and their coordination numbers are approximately 12. forming an alternate stacking sequence of flat and puckered layers along the c axis. Some me- tallic atoms have a defect structure. The interatomic distances of Fe, Cr and Ni are 0.2.2.— 0.2.66 nm, and the distances between Fe, Cr, Ni and C are 0.1893—0.2.69 nm. The coordina- tion number of carbon is 6. It occurs in interstices of the metallic atoms Fe, Cr and Ni to form trigonal-prismatically coordinated polyhedra. These coordination polyhedra are linked with each other via shared corners or shared edges into a new type of metal carbide structure.

关键词： Luobusha of Tibet, metal carbide, crystal structure.

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The developmental trend of labrum and median eyes of Orsten-type preserved Phosphatocopina (Crustacea)

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Science China Earth sciences 2010年第1期53卷 18-26页

作者： LIU Zheng 1,2.& DONG XiPing 1,2.1 School of Earth and Space sciences,Peking University,Beijing 100871,China 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing {4. of {2. and Palaeontology,chinese {4. of sciences,Nanjing 2.0008,China 1. School of Earth and Space sciences Peking University Beijing 100871 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Phosphatocopina (Crustacea,Arthropoda) is an important group of 'Orsten-type' preserved *** is resolved as the sister-group of *** we study the labrum,the median eyes,and the inner lamella of Phosphatocopina based on the selected specimens respectively from western Hunan,South China,and *** labrum characters of different species exhibit interspecific *** ratio of labrum length/shield length is significant to the reconstruction of the ontogeny of *** labrum characters should be introduced to the diagnosis of *** the earliest growth stage,the median eyes were inconspicuous,almost as flat as the other area of the ***,with the growth of the individuals they became *** were two obviously concave structures on the ventral side of the hypostome in later stages,which were the positions where the median eyes should have been *** addition,the two modes of preservation of the inner lamella,i.e.,that of shrinking and that of bulging up,are interpreted as the preservational artifact herein.

关键词： Phosphatocopina Crustacea Orsten-type preservation morphology ontogeny Cambrian South China Sweden

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Environmental records of lacustrine sediments in different time scales:Sediment grain size as an example

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Science China Earth sciences 2004年第10期47卷 954-960页

作者： CHEN Jing’an1, WAN Guojiang1, David Dian Zhang2. ZHANG Feng1 & HUANG Ronggui1 1. State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, chinese academy of sciences, Guiyang 550002. China 2. Department of Geography and {2., University of Hong Kong, Pokfulam Road, Hong Kong, China 1. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Department of Geography and geology University of Hong Kong Pokfulam Road Hong Kong China

Sediment grain size is a conventional proxy of climatic changes. Larger sediment grain size is often interpreted to indicate dry climate during lower lake level while smaller sedi- ment grain size implies wet climate during higher lake level. Through detailed study on sediment grain sizes in Lake Erhai and Lake Chenghai, this paper reveals the different indication signifi- cances of sediment grain sizes in different time scales, different resolution investigations. For long time-scale and low resolution (102. or 103a) studies, larger sediment grain size indicates lower lake level, smaller lake area and drier climate while smaller sediment grain size indicates higher lake level, larger lake area and wetter climate. For short time-scale and high resolution (a or 10a) studies, larger sediment grain size reflects more rainfall and wetter climate while smaller sediment grain size reflects less rainfall and drier climate. Environmental information revealed by lacustrine sediment records is often different in different time scales because of the variance of sedimentation resolution, sampling resolution and dating precision. Therefore, paleoclimate im- plications of environmental proxies in long time-scale and low resolution investigations could not be mechanically applied to short time-scale and high resolution studies. Only after synthetically analyzing the influence manner and extent of all factors on the sediment records in different time scales, can credible conclusions be obtained.

关键词： lacustrine sediment, environmental record, grain size, time scale.

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^(4.)Ar-^(39)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning Region: Age constraints on the Mesozoic tectonic events

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chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch Center of Mineral Resources Exploration, institute of geology and {2., chinese academy of sciences, Beijing 100101, China Guangzhou institute of Geochemistry, chinese academy of sciences, Guangzhou 51 Research Center of Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North China, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 4.Ar-39Ar plateau age of (2.9±4. Ma (Bi) and two samples from the latter gave 4.Ar-39Ar plateau ages of (116± 2. Ma (Bi) and (12.±3) Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 4.Ar-39Ar age biotite ductile shear zone West Liaoning Region.

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Searching for the remains of subducted continental slabs

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chinese Science Bulletin 2000年第5期45卷 385-386页

作者： LIU Guangdinginstitute of geology and {2., chinese academy of sciences, Beijing 100101, China institute of geology and {2. Chinese Academy of Sciences Beijing China

On the basis of oceanic geological and geophysical observations the global plate tectonics theory wasput forward in the late 1960s. It inherited the essence of mobilism of continental drift and sea-floorspreading, caused a revolution of earth sciences in the twentieth century. But plate tectonics cannotsatisfactorily explain the complicated geological phenomena of continents, it fails in elucidating

关键词： Searching for the remains of subducted continental slabs der Nature

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A new method for spatio-temporal prediction of rainfall-induced landslide

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Science China Earth sciences 2006年第4期49卷 421-430页

作者： DING Jixin1,2. YANG Zhifa2. SHANG Yanjun2. ZHOU Shenghua1 & YIN Juntao3 1. China Non-ferrous Metals Resource Geological Survey, Beijing 100012. China {4., chinese academy of sciences, Key Laboratory of Engineering Geomechanics, Beijing {2., China 3. School of Geoscience & Environmental Engineering, Central South University, Changsha 4.0083, China 1. China Non-ferrous Metals Resource Geological Survey Beijing 100012 China 2. institute of geology and geophysics Chinese Academy of Sciences Key Laboratory of Engineering Geomechanics Beijing 100029 China 3. School of Geoscience & Environmental Engineering Central South University Changsha 410083 China

Geological condition and rainfall are two most principal conditions inducing landslides in the Chongqing region. By analyzing the forming conditions of rainfall-induced landslides, a new method for spatio-temporal prediction of rainfall-induced landslide is brought forward on the basis of grading and overlapping geological condition and rainfall factor in this paper. At first, semi-quantitative assessment and grading for the geological condition of a certain area or slope can be carried out with the multi-factor interactive matrix. Then the severity of rainfall in that area is grading according to the maximum daily rainfall and the total rainfall in a rainfall course. Finally, the “landslide probability judgement factor” can be worked out through grading and overlapping “geological condition influenc- ing factor” and “rainfall influencing factor”, by which the landslide can be graded into 4.grades, they are landslide extremely easily happening, landslide easily happening, landslide difficultly happening and landslide hardly ever happening respectively. More accurate spatio-temporal prediction of rain- fall-induced landslides can come true on the ground of detailed geological survey of some dangerous slopes in an area and more precise weather forecast. Finally, the reliability and feasibility of carrying out the spatio-temporal prediction of rainfall-induced landslides with the method of “two factors” grading and overlapping are validated by the example of Jipazi landslide.

关键词： rainfall-induced landslide, geological condition, rainfall, two factors, grading and overlapping, interactive matrix, spatio-temporal prediction.

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Origin, Evolution and Mechanism of the Jehol Fauna

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 203-215页

作者： Wang Si’en institute of geology, {2. academy of Geological {4., Beijing Liu Linqun institute of geology Chinese Academy of Geological Sciences Beijing

This paper deals with the geographic distribution and geological setting of the Jehol (northeastHebei-southwest Liaoning-southeast Inner Mongolia) fauna, and discusses the origination and the evolution ofits major biological groups. It is demonstrated that the Yan-Liao (northern Hebei-western Liaoning) area is theprovenance for the fauna. Why the fauna originated and developed in the area was intimately related to suchfactors as the palaeoclimate, palaeogeography, crustal movement, volcanism and frequent reversals of magnet-ic polarity at that time, in addition to the internal factors of the organisms themselves.

关键词： Origin Evolution and Mechanism of the Jehol Fauna

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