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Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, China

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Science China Earth sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. institute of geology and Geophysics, chinese academy of {3., beijing 100029, China 2. Key Laboratory for Mineral Resources Research, chinese academy of {3., beijing 100029, China Correspondence should be addressed to Chu Xuelei (email: xlchu@***) 1. institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Key Laboratory for Mineral Resources Research Chinese Academy of Sciences 100029 Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13. values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13. values of carbonates increase from about -3. to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13. value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13. value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜13.0 Ma may signify two correlative global tectonic events.

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

Mantle-derived rare-gas releasing features at the Tianchi volcanic area, Changbaishan Mountains

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chinese Science Bulletin 1997年第9期42卷 768-771页

作者： SHANGGUAN Zhiguan and SUN Mingliang1. institute of geology, State Seismological Bureau, beijing 100029, China 2. Lanzhou institute of geology, {3. academy of sciences, Lanzhou 73.000, China institute of geology State Seismological Bureau Beijing China Lanzhou institute of geology Chinese Academy of Sciences Lanzhou China

TIANCHI volcano,Changbaishan Mountains isthe largest modern active volcano in East *** times strong volcanic erupting activ-ities occurred in the Cenozoic *** vol-canic activities have revived again in the *** investi... 详细信息

关键词： Tianchi volcanic area Changbaishan Mountains mantle-derived rare gas 3.e/ 4He 40 Ar/3. Ar 4He/20 Ne 4He/40Ar isotope ratios.

A Study of the Kunlun-Qilian-Qinling Suture System

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 364-374页

作者： BIAN Qiantao, GAO Shanlin, LI Dihui, YE Zhengren, CHANG Chengfa, LUO Xiaoquan institute of geology and Geophysics, chinese academy of {3., beijing 100029 Science Press, chinese academy of {3., beijing 100717 institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 Science Press Chinese Academy of Sciences Beijing 100717 [?]3.ian Qiantao Born in 1945 graduated from the Department of geology South-Central University of Technology in 1970 and obtained his master's degree and doctor's degree at the Graduate School and the Institute of Geology Chinese Academy of Sciences in 1981 and 1987 respectively. He is currently a professor of the Institute of Geology and Geophysics Chinese Academy of Sciences and has long been engaged in the research of tectonics petrology mineral deposits and geochemistry. Tel: (010) 62008058 E-mail: bianqt@***

The Late Neoproterozoic-Early Palaeozoic suture zones within the Central Orogenic Belt of China can be considered a system—the Kunlun-Qilian-Qinling suture system (KQQ suture system). It is basically divided into the western, central and eastern sectors. The western sector consists of the Küda-Subashi suture zone, the Mazar-Kangxiwar suture and the central West Kunlun microblock. The central sector covers the following five suture zones: the Altun, North Qilian, Qaidam northern marginal, Qimantag-Wutuo and East Kunlun southern marginal sutures, in addition to some microblocks such as the mid-south Qilian, Qaidam, Ayakkum and Maqen microblocks. The eastern sector is composed of the Shangdan suture zone, Mianlüe suture zone and central Qinling-Dabie microblock. The KQQ suture system experienced (1) extending-rifting of the Rodinia super-continent in the early-middle Sinian (～780–600 Ma); (2) the formation and evolution of the KQQ archipelagic ocean during the Late Sinian-Ordovician (～600–440 Ma), and (3. closing of the KQQ ocean and forming of the KQQ suture system during the Late Ordovician—early Silurian (～440–400 Ma). As a system comprising many suture zones and microblocks, the KQQ suture system constitutes the foundation of the Central Orogenic Belt of China.

关键词： A Study of the Kunlun-Qilian-Qinling Suture System

Control of atmospheric CO_2 concentrations by 2050: A calculation on the emission rights of different countries

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Science China Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2, GE QuanSheng3.& ZHANG ZhiQiang4 1 institute of geology and Geophysics, chinese academy of {3., beijing 100029, China 2 The General Office of chinese academy of {3., beijing 100864, China 3.institute of Geographic {3. and Natural Resources Research, chinese academy of {3., beijing 100101, China 4 The Lanzhou Branch of the National Science Library, the Scientific Information Center for Resources and Environment, Lanzhou 73.000, China institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China The General Office of chinese academy of sciences Beijing 100864 China institute of Geographic sciences and Natural Resources Research Chinese Academy

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2005, and their annual emissions allowances into the future (2006―2050), a 470 ppmv atmospheric CO2 concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2050, actual emissions from 1900 to 2005, emissions levels in 2005, and the average growth rate of emissions from 1996 to 2005―all countries and regions whose population was more than 3.0000 in 2005 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2005 had already expended their 2050 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (20 dollars per ton of CO2). Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2006 to 2050 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3.& SHAO Xuemei1,21. institute of Geographical sciences and Natural Resources Research, chinese {3. of sciences, beijing 100101, China 2. institute of Tibetan Plateau Research, chinese {3. of sciences, beijing 100085, China 3. Graduate School of chinese {3. of sciences, beijing 10003., China institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Graduate School of chinese academy of sciences Beijing China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3. The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

δ^13.sc values of the loess-paleosol sequence in Dali area, Shaanxi Province, China, and paleoenvironmental implications

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chinese Science Bulletin 2003年第9期48卷 902-907页

作者： LI Yumei & LIU Dongsheng (LIU Tungsheng)institute of geology and Geophysics, chinese academy of {3., beijing 100029 (e-mail: liyrney@***) 1. institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029

The carbon isotopic ratios of carbonate in the two profiles of the Dali area were analyzed and some new understandings on the influencing factors of the δ13.SC value of the loess-paleosol sequence and its paleoenvironmental implications were discussed preliminarily in this report. The 13.SC value of the Dali loess-paleosol sequence is synchronizing with the variance of magnetic susceptibility basically and the negative peaks of the δ13.SC curves are corresponding to the different developmental periods of the paleosol. It is believed that the intervention of the CO2 produced by plants will cause the decrease of the δ13.SC value, the amplitude of which may be relevant to the paleovegetation density and the ancient humidity. The relative biomass of C4 plants in the vegetation will affect the sublevel change of the δ13.SC. Low δ13.SC value by and large indicates the environmental conditions of the relatively abundant vegetation and humid climate. During the last 250000 years, the period with the sparsest vegetation and the most arid climate is the phase of the loess in L2 depositing and the period with the most abundant vegetation and the most humid climate is the last interglacial period. The δ13.SC curves of Dali also show that the High Temperature and Large Precipitation Event of the Qinghai-Tibetan Plateau during 40-3. kaBP had affected the Central Shaanxi Plain with relatively humid climate, and had apparent influence on the local vegetation and humidity.

关键词：古环境大理地区黄土陕西湿润气候碳同位素植被高温天气

Orogen-parallel extension in Himalaya: Is it the indicator of collapse or the product in process of compressive uplift?

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chinese Science Bulletin 2000年第2期45卷 114-120页

作者： ZHANG Jinjiang, DING Lin, ZHONG Dalai & ZHOU Yong institute of geology and Geophysics. chinese academy of {3.. beijing 100029, China institute of geology and Geophysics Chinese Academy of Sciences Beijing China

Extensional structures developed extensively in Himalaya with their strikes perpendicular to that of the orogenic belt. The studies of such structures in Qusum, Burang, Lhozhag, Nyalam and Yadong show that they represent an orogen-parallel extension. The basins produced by the extension experienced orokyn-perpendicular compression during their formation. The ages of the extension rang from 16 to 13.Ma and coincide with the intensive compressive stage in Southeastern Asia. Therefore, the extension is Syn-shortening and the dominate tectonic movement in Himalaya was compression and uplift during the extension. The extension was the partition of compressive deformation rather than the indicator for the collapse and falling of the Tibetan Plateau.

关键词： Himalayan orognic helt syn-shortening extension uplift

2002:The extra-strong warm winter event in North Asia and its accompanying anomalous atmospheric circulation

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chinese Science Bulletin 2003年第10期48卷 1031-1033页

作者： WANG Huijun LASG, institute of Atmospheric Physics, chinese academy of {3., beijing 100029, China LASG Institute of Atmospheric Physics Chinese Academy of Science China

Features of an extra-strong warm winter event in North Asia in 2002 and its accompanying anomalous atmospheric circulation were studied through diagnosis on the atmospheric reanalysis data set. Results show that the winter of 2002 is of the warmest in the recent 54 years in North Asia, which was caused by both decadal scale and interannual scale variability. The interannual variability is proved to be as the main cause for the event, and it is related to the global scale atmospheric circulation anomalies, with the strongest of them in the Eastern Hemisphere and in the middle and high latitude region of the Southern Hemisphere.

关键词：大气环流亚洲北部高强度暖冬现象天气资料

Two possible mechanisms for vortex self-organization

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Science China Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. chinese academy of Meteorological sciences, {3. 100081, China 2. Department of Space Information Science, Nanjing University of Information Science and Technology, Nanjing 210044, China 3. institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, China 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. chinese academy of Meteorological sciences Beijing 100081 China 3. institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.