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Carbon and Oxygen Stable Isotope Values and Microfossils at 4..4.4.5ka BP in Tai Co,Tibet,china,and Their Paleoclimatic Significance

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1036-1050+1052-1056+1051页

作者： ZHENG Mianping~(1,2,*),LIU Junying~(1,3),MA Zhibang~(1,4.,WANG Hailei~(1,2) and MA Nina~(1,2) 1 MLR Key Laboratory of Saline Lake Resources and Environment,institute of Mineral Resources,CAGS, Beijing 100037,china 2 Research and Development Center for Saline Lakes and Epithermal Deposits,chinese academy of Geological Sciences,Beijing 100037,china 3 institute of geology,chinese academy of Geological Sciences,Beijing 100037,china 4.Key Laboratory of Cenozoic geology and Environment,chinese academy of Sciences,Beijing {13.,{14. MLR Key Laboratory of Saline Lake Resources and Environment Institute of Mineral Resources CAGS Beijing 100037 China Research and Development Center for Saline Lakes and Epithermal Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Key Laboratory of Cenozoic geology and Environment Chinese Academy of Sciences Beijing 100029 China *Correspondence: Mianping ZHENG *Correspondence: Corresponding author. E-mail: zhengmp2010@***

Two sedimentary sections were measured at Tai Co(Co means lake in Tibetan) in western Tibet,*** two sections are almost all composed of clay carbonate beds except in their lower parts where there are carbonized plants at>10 cm depths and dark-colored carbonate clay and clay at 50-70 cm depths,yielding abundant gastropods,ostracods,and *** carbon and oxygen stable isotope values of carbonate,ostracods,and charophytes and ecological features of microfossil communities indicate the following climatic change in the area from 4..4.to 4.5 ka BP:at 4..4.26.2 ka BP,the climate was relatively wet;at 26.2-25.5 ka BP,it was slightly warm-dry;at 25.5-22.5 ka BP,it was warm-wet;at 22.5-21.0 ka BP,it was slightly cold-wet;at 20.5-17.5 ka BP,it became cold abruptly and slightly wet,implying the climate of the last glacial maximum;at 17.5-16.0 ka BP,it was slightly cold-dry;at 16.0-11.8 ka BP,it was slightly warm-wet;at 11.8-10.4.ka BP,it was relatively cold-dry, roughly equivalent to the climate of the Younger Dryas,and at 10.4.ka BP,the temperatures began to rise again;at 10.4.9.4.ka BP,it was slightly warm-wet;at 9.4.8.5 ka BP,there occurred short warm-wet oscillations;at 8.5-7.9 ka BP,it was slightly dry-cold,representing a strong temperature-lowering and drying event in the postglacial stage;at 7.8-6.3 ka BP,it was slightly warm-wet;at 6.3-4.5 ka BP,the climate tended to be cold-dry.4.5 ka BP recorded the maximum aridity since the late part of the late Pleistocene.

关键词： sedimentary environment index paleoclimatic changes late Pleistocene-Holocene(4..4.4.5 ka BP) Tai Co Tibet

Geochemical research on C-O and Sr-Nd isotopes of mantle-derived rocks from Shandong Province, china

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Science china Earth Sciences 2004年第2期47卷 171-180页

作者： LIU Jianming, ZHANG Hongfu, SUN Jinggui & YE Jie1. institute of geology and geophysics, chinese {4. of Sciences, Beijing 10002., china 2. School of Earth Science, Jilin University, Changchun 13.061, china Correspondence should be addressed to Liu Jianming (email: jmliu@***) 1. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China 2. School of Earth Science Jilin University 130061 Changchun China

This paper presents systematic studies on the C-O and Sr-Nd isotopic compositions for Cretaceous Badou carbonatites, Fangcheng basalts, and Jiaodong lamprophyres and Paleozoic Mengyin kimberlites in Shandong Province, china. Paleozoic kimberlites have normal and uniform C-O isotopic compositions with δ13. and δ18O in the range of -4.8‰--7.6‰ and +9.9‰-+13.2‰, respectively. However, Cretaceous three different types of mantle-derived rocks have quite different C-O isotopic compositions, indicating that the mantle sources are probably partially contaminated with organic carbon-bearing crustal materials. These Cretaceous rocks show uniform and EMII-like Sr-Nd isotopic compositions and also indicate that the mantle sources were affected by recycled crustal materials. Comparative studies of C-O and Sr-Nd isotopes reveal that the lithospheric mantle beneath the eastern North china Craton had different isotope characteristics in the Paleozoic, the early Cretaceous, and the Tertiary time. This demonstrates that the lithospheric mantle beneath the region underwent at least twice reconstructions since the Paleozoic. Available data imply that the first reconstruction mainly happened during the Triassic-Jurassic time with gradual changes and the second in the Cretaceous with abrupt changes. Results also show that the early Cretaceous (especially at 120-13. Ma) was perhaps the key period leading to the dramatic change of the Mesozoic geodynamics on the eastern North china Craton.

关键词： mantle-derived rocks, carbonate minerals, C-O isotope, Sr-Nd isotope, lithospheric mantle, Shandong.

The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of china

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South china Sea institute of Oceanoiogy, chinese academy of Sciences. Guangzhou 510301, china:geology and geophysics institute. chinese academy of Sciences, Beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China geology and geophysics institute Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.24.decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

Discovery of Cathaysiodendron Lee from the Early Carboniferous of Jingyuan,Gansu,western china

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Progress in Natural Science:Materials International 2004年第10期14卷 63-66页

作者： WANG Jun and WU Xiuyuan (Nanjing institute of geology and Palaeontology,chinese academy of Sciences,Nanjing210008,{4.) chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China

As one of the representative members of the Late Palaeozoic Cathaysian flora,Cathaysiodendron has been previously recorded from the Early Permian Taiyuan and Shanxi Formations in north *** species of Cathaysiodendron presented here are from the lower member of Chouniugou Formation of Ciyao,Jingyuan,*** overlying marine beds yield fusulinids that are of Visean age in western Europe and conodonts of the Datang Stage in south china,so that the age of the bed containing Cathaysiodendron as Visean,Early Carboniferous,is well *** a record of Cathaysiodendron is significant in terms of Carboniferous phyto-geography and the evolution of the Cathaysian Lepidophytes.A new species,Cathaysiodendron jingyuanense Wang&Wu *** described and a second one mentioned.

关键词： Cathaysiodendron Early Carboniferous Visean Cathaysian flora

Discovery of the budding phosphatized globular fossils from the Neoproterozoic Doushantuo Formation at Weng'an, Guizhou Province, china

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Progress in Natural Science:Materials International 2006年第10期16卷 1079-1083页

作者： LIU Pengju , YIN Chongyu and TANG Feng (institute of geology, chinese academy of Geological Sciences, Beijing 100037,{4.) [a]institute of geology Chinese Academy of Geological Sciences Beijing China

There is much debate on biological affinities of the phosphatized globular fossils from the Neoproterozoic Doushantuo phosphorites at Weng’an, Guizhou Province. Here we report for the first time the budding structures of some of these globular fossils, which have previously been interpreted as the resting eggs and early cleavage embryos of metazoans. The budding structures are similar to the germinating tubes of the spore and zygote of living algae, suggesting that some globular fossils from the Doushantuo phosphorites bear affinity with algae. The present new information indicated various biological affinity of the phosphatized globular fossils from the Doushantuo phosphorites.

关键词： Neoproterozoic Donshantuo Formation globular fossil budding structure algae resting eggs embryos.

S-wave velocity and Poisson's ratio structure of crust in Yunnan and its implication

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Science china Earth Sciences 2005年第2期48卷 210-218页

作者： HU Jiafu, SU Youjin, ZHU Xiongguan & CHEN Yun Geophysical Department of Yunnan University, Kunming 650091, china Seismological Bureau of Yunnan Province, Kunming 65004., china institute of geology and {4., chinese academy of Sciences, Beijing 100101, china 1. Geophysical Department of Yunnan University 650091 Kunming China 2. Seismological Bureau of Yunnan Province 650041 Kunming China 3. institute of geology and geophysics Chinese Academy of Sciences 100101 Beijing China

Receiver function of body wave under the 23 stations in Yunnan was extracted from 3-component broadband digital recording of teleseismic event. Thus, the S-wave velocity structure and distribution characteristics of Poisson's ratio in crust of Yunnan are obtained by inversion. The results show that the crustal thickness is gradually thinned from north to south. The crustal thickness in Zhongdian of northwest reaches as many as 62.0 km and the one in Jinghong of further south end is only 30.2 km. What should be especially noted is that there exists a Moho upheaval running in NS in the Chuxiong region and a Moho concave is generally parallel to it in Dongchuan. In addition, there exists an obvious transversal inhomogeneity for the S-wave velocity structure in upper mantle and crust in the Yunnan region. The low velocity layer exists not only in 10.0-15.0 km in upper crust in some regions, but also in 30.0-4..0 km in lower crust. Generally, the Poisson's ratio is on the high side, however it has a better corresponding relation to the crustal velocity structure. An obvious block distribution feature is still shown on such a high background of Poisson's ratio. It is discovered by synthetically analyzing the velocity structure and Poisson's ratio distribution that there are high Poisson's ratio and complicated crust-mantle velocity structure feature in the Sichuan-Yunnan Diamond Block with Xiaojiang fault to be the east boundary and Yulong Snow Mountain fault to be the west boundary besides the frequent seismicity. This feature differs obviously from that of surrounding areas, which would provide geophysical evidence to deeply study the eastwardly flowage of lithospheric substances in the Qinghai-Tibet Plateau.

关键词： Yunnan, S-wave velocity, Poisson's ratio, Sichuan-Yunnan Diamond Block.

^(14.C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou institute of Geochemisry, chinese academy of Sciences, Guangzhou 51064., china institute of geology, chinese academy of Sciences , Beijing 10002., china South china institute of Botany, chinese academy of Sciences, Guangzhou 510650, china Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of geology Chinese Academy of Sciences Beijing China South china institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14. values of these profiles decrease with increasing of depth. The Δ14. values in 30—4. cm depth int... 详细信息

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14./sup>C values of these profiles decrease with increasing of depth. The Δ14./sup>C values in 30—4. cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14./sup>C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 4.5 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14./sup>C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14. tracing 14. apparent age.

Garnet Sm-Nd and U-Pb systems: A case study of a granulite from the European Variscan belt

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chinese Science Bulletin 2002年第15期47卷 1284-1288页

作者： CHEN FukunInstitut fur Mineralogie, Petrologie und Geochemie, Universitat Tubingen, 72074.Tubingen, Germany institute of geology and geophysics, chinese {4. of Sciences, Beijing 10002., china Institut für Mineralogie Petrologie und Geochemie Universität Tübingen Tübingen Germany institute of geology and geophysics Chinese Academy of Sciences Beijing China

This study presents zircon and garnet ages of a mafic granulite from the high-grade Variscan basement of the Black Forest, Germany and discuss isotope closure temperature of garnet Sm-Nd and U-Pb systems. Zircon grains yield 207Pb/206Pb ages between -34. and -4.4.Ma by the U-Pb and evaporation methods. In contract, garnet dating gives Sm-Nd and Pb-Pb isochron ages of (398±3) Ma and (4.1±14. Ma, respectively, which are older than most of zircon ages. These data imply that most of zircons lost radiogenic Pb, probably due to metamictization or recrystallisa-tion during the granulite-facies metamorphism (-800°C) at -34. Ma. Garnet Sm-Nd and U-Pb systems preserve chronological information of pro-grade metamorphism, probably profiting from a fluid-absence metamorphic environment. These results demonstrate that garnet mineral can be a better candidate than zircon mineral to date high-grade metamorphism by the U-Pb and Sm-Nd methods in some cases.

关键词： Variscan granulite garnet Sm-Nd U-Pb.

Preface——Jurassic of china and Environs: Stratigraphy, Basin History, and Paleoenvironment

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Science china Earth Sciences 2009年第12期52卷 1871-1872页

作者： SHA JinGeng LPS, Nanjing institute of geology and Palaeontology, chinese academy of Sciences, Nanjing 210008,{4. LPS Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The Jurassic is a geologically very complicated period in Earth history, spanning from 200 to 14. Ma. The Pangean supercontinent and even the Gondwana-land broke up, and the violent circum Paleo-Pacific (Yanshan) or... 详细信息

关键词： Preface and Paleoenvironment Stratigraphy Jurassic of china and Environs Basin History