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Orogenic and Anorogenic Granitoids in the Altay Mountains of Xinjiang and Their Discrimination Criteria

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 45-64页

作者： Zou Tianren Institute of Mineral Deposits, chinese academy of geological sciences, beijing Chao Huizhi and Wu Baiqing Xinjiang Institute of geology, Ministry of Metallurgical Industry Urumqi, Xinjiang Jiang Minxi 1Teliti and Yang Yueqing also participated in the field work. Those who participated in the laboratory study also include Yang Bingbin Duan Shangzhi Lü Qiaoling Li Longqi and Yu Shimei.

On the basis of field geological studies of the granotoids in the region, mineralogical, petrological, geochemical(including stable isotope geochemical) and isotopic geochronological investigations were carried out on selected representative granitic bodies of various types. The authors have concluded that, apart from the bodies of the orogenic granitoid series, there also exist intrusions of the anorogenic granitoid series in the region. The intrusives of the two series were formed not only in different ages and tectonic environments, but also were derived from different sources of materials. Moreover, they are associated with different mineralizations, belonging to different minerologenetic series(Cheng et al., 1983). They show distinctly a series of discriminative criteria. The problems under discussion in the present paper are of important theoretical and practical significance in the studies of granites of the orogenic belt, particularly the studies of the genesis and related metallogeny of the granites of the region.

关键词： Orogenic and Anorogenic Granitoids in the Altay Mountains of Xinjiang and Their Discrimination Criteria

Impact of changing atmospheric CO_2 concentrations over the Phanerozoic on stomatal parameters of vascular land plants

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chinese Science Bulletin 1999年第7期44卷 577-582页

作者： SUN Qigao, CHEN Liqun and LI ChengsenInstitute of Botany, chinese academy of sciences, beijing 100093, china, Institute of Botany Chinese Academy of Sciences Beijiing China

A novel and multi-disciplinary subject involving the relationships between changes in atmospheric CO2 concentration throughout the geological history and features of plant anatomy is reviewed. Particular attention will be given to stomatal parameters （stomatal density and stomatal index） which are recorded at a cellular level in fossil plants and the relationships of these observable parameters to earth life history and global environmental change. Trends of atmospheric CO2 concentrations during the Phanerozoic period are briefly introduced and recent conceptual advances in understanding the causal mechanisms for changes in stomatal parameters of land vascular plants are considered, In addition, some of the inherent problems and limitations of this kind of work are discussed and future research directions are presented.

关键词： Phanerozoic atmospheric CO2 concentrations vascular plants stomatal parameters.

Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in china

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Journal of Mountain Science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng Institute of Geographic sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 China Center for chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China Graduate University of the chineseacademy of sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method

Temporal variations of δ^(18)O of atmospheric water vapor at Delingha

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Science china Earth sciences 2008年第7期51卷 966-975页

作者： YIN ChangLiang1, YAO TanDong2, TIAN LiDe2, LIU DongNian3, YU WuSheng2 & QU DongMei2 1 State Key laboratory of Cryoshperic Science, Cold and Arid Regions Environmental and Engineering research Institute, chinese academy of sciences, Lanzhou 730000, china 2 laboratory of Environment and Processes, Institute of Tibetan Plateau research, chinese academy of sciences, beijing 100085, china 3 Meteorological Observatory of Haixi Prefecture of Qinghai Province, Delingha 817000, china 1. State Key laboratory of Cryoshperic Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. laboratory of Environment and Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China 3. Meteorological Observatory of Haixi Prefecture of Qinghai Province Delingha 817000 China

Oxygen stable isotope of atmospheric water vapor is widely used to study the modern process of cli- mate. Atmospheric water vapor samples were collected at Dlingha, northeast of Tibetan Plateau during the period from July 2005 to February 2006. The variation of δ18O and the relationships between δ18O and both the temperature and specific humidity are analyzed in this paper. Results show that the sea- sonal variation of δ18O of atmospheric water vapor at Delingha is remarkable with higher δ18O in summer and lower δ18O in winter. The temporal variation of vapor δ18O shows obvious fluctuations, with magnitude of over 37‰. The daily variation of the δ18O is highly correlated with air temperature. The relationship between δ18O and atmospheric water vapor content is complex. Study shows that δ18O of atmospheric water vapor is positively correlated with specific humidity in winter in seasonal scale and inversely correlated with specific humidity in summer rainy period. The δ18O values of at- mospheric water vapor are lower than those of precipitation at Delingha, and the average difference is 10.7‰. Variations of δ18O of atmospheric water vapor is also found to be affected by precipitation events, The model results show that the precipitation effect could have caused the vapor δ18O in the raining season to lower by 7% in average in July and August.

关键词： Delingha δ18O atmospheric water vapor

Constraints on the Archean atmospheric oxygen and sulfur cycle from mass-independent sulfur records from Anshan-Benxi BIFs, Liaoning Province, china

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Science china Earth sciences 2007年第10期50卷 1471-1478页

作者： HOU KeJun1,2, LI YanHe1,2? & WAN DeFang1,2 1 Key laboratory of Metallogeny and Mineral Resource Assessment, Institute of Mineral Resource, chinese academy of geological sciences (CAGS), beijing 100037, china 2 Key laboratory of isotope geology, CAGS, beijing 100037, china 1. Key laboratory of Metallogeny and Mineral Resource Assessment Institute of Mineral Resource Chinese Academy of Geological Sciences (CAGS) Beijing 100037 China 2. Key laboratory of isotope geology CAGS Beijing 100037 China

The Archean atmospheric oxygen concentration and sulfur cycle was long debated. The banded iron formation (BIF) is a special type of the sedimentary formation, which has truly recorded the atmospheric and oceanic conditions at that time. In this study, the composition of multiple sulfur isotope (δ 34S/δ 33S/δ 32S) for sulfides bedded in the Archean (~2.7 Ga) BIFs, in Anshan-Benxi area of Liaoning Province has been measured. The value of △33S varies from -0.89‰ to +1.21‰, which shows very obvious mass-independent fractionation (MIF) signatures. These non-zero △33S values indicate that the Archean sulfur cycles are different from what it is today, which have been deeply influenced by gas phase photochemical reactions. Algoma-type BIFs which are closely related to the volcanic activity have negative △33S value, however, Superior-type BIFs which are far away from the volcanic center have positive △33S value. The δ 34S varies in a large range from -22.0‰ to +11.8‰, which indicates that the bacteria reduction activity has already existed at that time, and that the oceanic sulfate concentration has at least reached 1 mmol/L in local areas. Combined with the contemporaneous existence of the hematite, magnetite and the occurrence and preservation of the sulfur MIF, it can be inferred that the Archean atmospheric oxygen level must be at 10-2―10-3 of the present atmospheric level (PAL).

关键词： sulfur mass-independent fractionation, Anshan-Benxi area, BIF, Archean atmospheric oxygen level, Archean sulfur cycle

Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic

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chinese Science Bulletin 2003年第13期48卷 1375-1380页

作者： ZHANG Tonggang, CHU Xuelei, ZHANG Qirui, FENG Lianjun & HUO Weiguo Key Lab of Mineral Resources Exploration and research, Institute of geology and Geophysics, chinese academy of sciences, beijing 100029, china Key Lab of Mineral Resources Exploration and research Institute of Geology and Geophysics Chinese Academy of Sciences China

Successive analyses of sulfur and carbon isotopic compositions of carbonates strata in the Doushantuo Formation in the Yangtze area were accomplished through a method of extracting trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were estimated from the samples that show the least diagenetic alteration. A high-resolution age curve of sulfur isotopes in seawater sulfates was obtained in the Doushantuo stage, which reflects the trend of variation in seawater sulfur isotopes after the Neoproterozoic snowball Earth event. Similar characteristics of variation in carbon isotopes were observed in the coeval carbonates. A large positive d 34S excursion over +20?occurs in ancient seawater sulfates in the early Doushantuo stage. Simultaneously, the d 13C values in ancient seawater carbonates exhibit a positive excursion up to 10. The maximum d 34S and d 13C values are +46.4 and +6.9? respectively. In the middle Doushantuo stage, the range of variation in d 34S values of seawater is relatively narrow, but d 13C values are quite high. Then, d 34S values of seawater become oscillating, and the same occurs in d 13C values. Negative excursions in d 34S and d 13C values occur simultaneously at the end of the Doushantuo stage, and the minimum d 34S and d 13C values dropped down to -10.1 and -5.7? respectively. The characteristics of variations in the sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment that became beneficial to inhabitation and propagation of organism. The organic productivity and burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable after the global glaciation. The global climate and environment possibly were fluctuating and reiterating. The negative excursions in d 34S and d 13C values occurring at the end of the Doushantuo stage may represent a global event, which might be related to oxidation of dee

关键词：硫碳同位素分馏新元古代成岩作用

Carbon isotope composition and its implications of Lower Cretaceous Aptian-Albian shallow water carbonates in the Cuoqin Basin, North Tibet

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Science china Earth sciences 2004年第3期47卷 247-254页

作者： ZHU Jingquan1, LI Yongtie2, JIANG Maosheng1 & CHEN Daizhao1 1. Institute of geology and Geophysics, chinese academy of sciences, beijing 100029, china 2. research Institute of Petroleum Exploration and Development, CNPC, beijing 100083, china chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China CNPC Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China

The d 13C values of Lower Cretaceous Aptian-Albian platform-type carbonates in the Cuoqin Basin, North Tibet vary between 2.48 and 5.46. The mean value is 3.93. The values are not only provided with positive excursion, but also 1.17 higher than those of con-temporaneous pelagic carbonates which possess pretty high d 13C values. The origin is ap-proached. During the oceanic anoxic events, a great number of organisms were rapidly buried, causing the increase of the d 13C value of oceanic total dissolved carbon (TDC) and generally promoting the values of marine carbonates. After that, owing to the organisms undergoing dif-ferent isotopic fractionation in the paleo-ocean with stratified structure, d 13C values of shallow sea carbonate were obviously higher than those of pelagic carbonates.

关键词： shallow water carbonate, stable carbon isotope, paleooceanography, Aptian-Albian stage, Cuoqin Basin.

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 academy of sciences, beijing 100029, china 2. School of Earth Science, Jilin University, Changchun 130061, 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 δ13C 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 120-130 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.

Quartz-Ferberite Oxygen isotope Geothermometer and Its geological Applications

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 271-281页

作者： Ding Tiping Liu Yushan Wan Defang Liu Zhijian Li Jincheng Zhang Guilan Institute of Mineral Deposits, chinese academy of geological sciences, beijing Institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing

Experiments for oxygen isotope exchange between ferberite and water were carried out and the followingequation on oxygen isotope fractionation between ferberite and water against temperature was obtained:Combining this equation with the equation of Clayton et al. (1972) on oxygen isotope fractionation be-tween quartz and water, an equation on oxygen isotope fractionation between quartz and ferberite was ob-tained:The Bigeleison-Mayer function method was used to calculate the oxygen isotope fractionation betweenquartz and ferberite. The theoretical curve obtained agrees with the experimental calibration results quite wellin the temperature range of *** above calibrated equation has been used in 5 world famous tungsten deposits to determine their tem-peratures of formation. The results show that the temperature range for an idividual deposit determined by thisgeothermometer agrees with those obtained from fluid inclusion determination and other isotopegeothermometers.

关键词： geothermometer oxygen isotope quartz--ferberite