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中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： jing-Bo Chen~(1*) and Shu-Yuan Du~(1,2. 1 Key Laboratory of Petroleum Geophysics,institute of {2. and Geophysics,chinese Academy of sciences,PO Box 982., beijing 10002.,china,and 2.Graduate University of chinese Academy of sciences,beijing 100049,china

The phase-shift-plus-interpolation and extended-split-step-Fourier methods are wavefield-continuation algorithms for seismic migration *** two methods can be applied to regions with complex geological *** on their unified separable formulas,we show that these two methods have the same kinematic characteristics by using the theory of pseudodifferential *** tests on a Marmousi model demonstrate this *** important aspect of these two methods is the selection of reference velocities and we explore the influence of the selection of reference velocities by comparing the geometric progression method and the statistical *** show that the geometric progression method is simple but does not take into account the velocity distribution while the statistical approach is relatively complex but reflects the velocity distribution.

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Magnetostratigraphy and sedimentology of the eolian deposits since the late Miocene in northern china and the paleoclimatic implications

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Magnetostratigraphy and sedimentology of the eolian deposits...

中国科学院地质与地球物理研究所2.02.术年会

作者： Shiling Yang,zhongli ding {2. of {3. and Geophysics,chinese Academy of sciences,beijing 10002.,china

In this article,two thick loess-red clay sequences located at Lingtai and jingchuan,the chinese Loess Plateau,are studied with emphases on magnetostratigraphy and sedimentology. Paleomagnetic measurements show that the jingchuan red clay has a basal age of 8.0 Ma,which is one million years older than the previously studied Lingtai *** observations and grain size analyses both suggest an eolian origin of the red clay sediments at Lingtai and jingchuan,thus extending available records of the eolian deposits in the Loess Plateau from 2.6 Ma back to 7.0-8.0 *** of five red clay sections in the Loess Plateau suggests that the Lingtai red clay sequence has a relatively continuous nature of sedimentation and can be regarded as the type-section of the Tertiary red clay deposits in northern *** the basis of spatial changes in the grain size of one northwest-southeast loess transect,several semiquantitative models of grain size parameters versus the minimum distance from the source region to depositional areas were developed. According to these models,the estimated eastern margin of the desert in northern china during the Tertiary red clay development is similar to that of the present Badain Jaran *** reconstruct the long-term East-Asia monsoon history from the celebrating eolian red clay-loess deposits,the ratios of CBD-extractable FeO to total FeO concentrations in the Lintai red clay-loess sequence,the proxy indicator for the summer monsoon changes,were *** Lingtai FeO ratio record indicates that the East-Asia summer monsoon has experienced a non-linear evolution over the past seven million *** strongest East Asia summer monsoon may occur between 4.1 and 4.8 Ma, which may be causally related to the relatively small ice volume and high global temperature during the early Pliocene.

关键词： loess red clay eolian deposits grain size paleomonsoon

A TENTATIVE CORRELATION OF CLIMATE CHANGES BETWEEN CENTRAL china AND HIGH LATITUDE IN THE NORTH HEMISPHERE

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中国科学院大学学报 1999年第1期 72-80页

作者： Ren Janzhang (china Japan Friendship Center for Environmental Protection,beijing {2.) Liu Tungsheng {3. zhongli Zhou Xiaoquan (institute of geology,chinese Academy of sciences,beijing {2.) Quan Hao\ Di Yan (china Japan Friendship Center

１ＩｎｔｒｏｄｕｃｔｉｏｎＬｏｅｓｓｄｅｐｏｓｉｔｓａｒｅａｋｉｎｄｏｆｔｙｐｉｃａｌｔｅｒｒｅｓｔｒｉａｌｓｅｄｉｍｅｎｔｓｗｉｄｅｓｐｒｅａｄ，ｃｏｖｅｒｉｎｇａｂｏｕｔ１０ｐｅｒｃｅｎｔｏｆｌａｎｄｓｕｒｆａｃ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＬｏｅｓｓｄｅｐｏｓｉｔｓａｒｅａｋｉｎｄｏｆｔｙｐｉｃａｌｔｅｒｒｅｓｔｒｉａｌｓｅｄｉｍｅｎｔｓｗｉｄｅｓｐｒｅａｄ，ｃｏｖｅｒｉｎｇａｂｏｕｔ１０ｐｅｒｃｅｎｔｏｆｌａｎｄｓｕｒｆａｃｅｏｆｔｈｅＥａｒｔｈ．Ｔｈｅｍａ...

关键词： chinese loess greenland ice cap dust high frequent climate change

High-resolution carbon isotope record for the Paleocene-Eocene thermal maximum from the Nanyang Basin,Central china

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High-resolution carbon isotope record for the Paleocene-Eoce...

中国科学院地质与地球物理研究所第十届(2.10年度)学术年会

作者： ZHU Min~(1,2.),ding zhongli~1,WANG Xu~1,CHEN ZuoLing~1,JIANG HanChao~3. DONG XinXin~1,JI JunLiang~4,TANG ZiHua~1 & LUO Pan~1 1 Key Laboratory of Cenozoic {2. and Environment,institute of {2. and Geophysics,chinese Academy of sciences,beijing 10002., china 2.The Graduate University of chinese Academy of sciences,beijing 100049,china 3.State Key Laboratory of Earthquake Dynamics,institute of {2.,china Earthquake Administration,beijing 10002.,china 4 Key Laboratory of Bio{2. and Environmental {2.,Ministry of Education,china University of Geosciences,Wuhan 43.074,china

The Paleocene-Eocene thermal maximum(PETM) was a transient episode of global warming,associated with massive atmospheric greenhouse gas input that occurred at the Paleocene/Eocene *** and isotope stratigraphic studies indicate that the PETM event is well documented in the marl deposits of the Yuhuangding section in the Nanyang Basin,Central china,with a carbon isotope negative excursion of～6.1‰within 19-m-thick marl *** is the highest resolution record of the PETM so far found in the *** PETM event was triggered within 2.cm-thick marl sediments,with a decrease ofδC (stable carbon isotope ratio) from -3.2.to -5.2.,suggesting a massive methane hydrate release for a transient period that was possibly caused by a catastrophic event.A comparison between marine and terrestrial records indicates a"Three-Phase Model"for the PETM *** there is a rapid negative excursion in theδC record,followed by a slowly decreasing trend,and then a gradual positive recovery,corresponding respectively to a rapid dissociation of oceanic methane hydrate,followed by a slow release of methane and then the consumption of the released methane.

关键词： PETM carbon isotope greenhouse gases Nanyang Basin

Winter-Spring precipitation as the principal control on predominance of C3.plants in Central Asia over the past 1.77 Myr:evidence fromδ13. of loess organic matter in Tajikistan

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Winter-Spring precipitation as the principal control on pred...

中国科学院地质与地球物理研究所2.06学术年会

作者： Shiling Yang,zhongli ding {2. of {3. and Geophysics,chinese Academy of sciences,beijing 10002.,china

Although changes in atmospheric CO levels are thought to be the major factor driving long-term C/C vegetation evolution,recent studies tend to emphasize the effect of regional climate conditions on C/C *** middle latitudes(3.-45°),in which C/C plants are highly sensitive to environmental changes,provide an optimal basis for the investigation of the relative impacts of climate and pCO on shifts in C/C *** order to assess the factors controlling these shifts as well as the complex interactions between environmental factors,the carbon isotopic composition of bulk organic matter from the Chashmanigar loess section(southern Tajikistan) was measured for the past 1.77 *** general,theδC record shows mostly negative values throughout the sequence,almost allδC values falling between -2. and -2.‰,indicating a predominance of C plants in Central Asia over this time period,despite the presence of numerous glacial-interglacial *** 0.85 Myr to the present,theδC values become increasingly positive,reflecting a growing C ***,this C component is not detectable prior to 0.2. Myr,after which minor peaks are evident at～2.8,～171 and～18 ***δC record from Chashmanigar indicates that winter-spring precipitation,*** climatic conditions, have characterized Central Asia throughout the past 1.77 Myr,leading to the predominance of C *** the context of glacial-interglacial-scale changes in atmospheric CO,therefore,it is climate rather than pCO that controls C/C variations in Asia’s middle *** gradual increase in the C component since 0.85 Myr,especially the notable peaks after 0.2. Myr,may have been caused by an increase in summer precipitation due to an enhanced southward shift of the climate zones.

关键词： carbon isotopes of organic matter C3.and C4 plants loess precipitation seasonality climate zones Central Asia

On-line measurements ofδ15N in biological fluids by a modified continuous-flow elemental analyzer with an isotope-ratio mass spectrometer

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On-line measurements ofδ15N in biological fluids by a modif...

中国科学院地质与地球物理研究所2.08学术年会

作者： Xu Wang~(1*),Lianjun Feng~2.Fusong Zhang~2.and zhongli {3.~1 1 Key Laboratory of Cenozoic {2. and Environment,institute of {2. and Geophysics,chinese Academy of sciences, RO.Box 982.,beijing 10002.,china 2.Lab for Stable Isotope Geochemistry,institute of {2. and Geophysics,chinese Academy of sciences,RO.Box 982., beijing 10002.,china

A modified continuous-flow elemental analyzer coupled to an isotope-ratio mass spectrometer (modified EA-IRMS) was tested for on-lineδN measurement on urea solution and biological fluids (***).The elemental analyzer configuration was adapted by adding a U-shaped cold trap and an X-pattem four-way valve for on-line trapping/venting of water from the liquid *** indicate that theδN ratios show little variation(standard deviation(SD) = 0.05‰) with a sample size above the equivalent N yield of 0.2.mg urea(0.092.mg N) when the mass spectrometer conditions were carefully *** contrast,a significant logarithmic decrease inδN with sample size was observed but this can be offset by applying a linearity correction or blank correction when the sample size is between equivalent N yields of 0.05 and 0.2.mg *** blank correctedδN ratios give an overall precision of .16‰whereas the average precision forδN corrected using combined linearity and shift correction is 0.05‰.The relatively large variation in blank correctedδN values may be attributed to the variability of the blankδN in the ***,the blank correction should be carefully performed in routine *** a result,the linearity range of a modified EA-IRMS can be extended to a minimum sample size of 0.02. mg *** addition, the reproducibility of the new system is good,as indicated by the precision(2.) for a set of standards and *** data show that fluids containing nitrogen can be successfully analyzed in the modified EA-IRMS.

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Iron speciation in cherts from the Laobao Formation,South china:Implications for anoxic and ferruginous deep-water conditions

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Science Bulletin 2010年第Z2期 3189-3196页

作者： CHANG HuaJin 1,2.3.CHU XueLei 3.FENG LianJun 3.&HUANG jing 3.1School of Life and Geography sciences,Qinghai Normal University,Xining 810008,{2. 2.Key Laboratory of Tibetan Plateau Environment and Resources,Ministry of Education,Xining 810008,{2. 3.6} of geology and Geophysics,chinese Academy of sciences,beijing 10002.,{2.

Cherts in the Laobao Formation in the Silikou section,South china were deposited in terminal Ediacaran *** speciations of iron in cherts,such as pyrite Fe(FeP),HCl-extractable Fe(FeH),and total Fe(FeT),and their interrelationships,are proxies for distinguishing oxic,anoxic but ferruginous,and sulfidic conditions,which is an effective method for studying the terminal Ediacaran ocean *** chert samples from the Laobao Formation,pyrite concentrations are generally low(2. and 0.84 and most exceed 0.3.,and most of FeT/Al ratios range from 0.55 to 5.87(averaging 1.1).Relatively high content of highly reactive Fe and low content of pyrite indicate a scarcity of H2. and Fe-enriched *** features suggested that the deposition setting of Laobao cherts was anoxic and *** Ediacaran deep-water in the South china Basin was most likely anoxic and ferruginous,which played a key role in the emergence and evolution of early multicellular life.

关键词： cherts iron species paleoenvironment Ediacaran South china

Changes of the trace metals in ice core during 1915-2.16 in coastal eastern Antarctica

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Advances in Climate Change Research 2024年第4期15卷 596-608页

作者： jing-Wen LIU Chuan-Jin LI Gui-Tao SHI Yan LIU Zhi-Heng DU Ming-Hu ding Shao-Peng GAO Cun-De XIAO Shi-Chang KANG Bo SUN State Key Laboratory of the Cryosphere Science Northwest Institute of the Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China University of chinese Academy of sciences Beijing 100049China Key Laboratory for Polar Science of State Oceanic Administration Polar Research Institute of ChinaShanghai 200136China Key Laboratory of Geographic Information Science(Ministry of Education) School of Geographic Sciences and Institute of Eco-ChongmingEast China Normal UniversityShanghai 200241China institute of Tibetan Plateau and Polar Regions Meteorology Chinese Academy of Meteorological SciencesBeijing 100081China Key Laboratory of Tibetan Environment Changes and Land Surface Processes Instituie of the Tibetan PlateauChinese Academy of SciencesBeijing 100101China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China

Antarctic trace metal records provide important information for grasping the influence of human activities on the environment over the last *** CA2.16-75 ice core is located along the East Antarctic Zhongshan Station-Dome A,enhances the record of metals research in the East Antarctic region,and its high-resolution supplies data support for the study of high-frequency climatic drivers and the effect of human activities on the Antarctic environment.A thorough dataset on seven trace metals(Al,Fe,Mn,Cu,Zn,Ba and Pb)in a coastal ice core in eastern Antarctica during the previous 102.years(1915-2.16)is presented in this *** has the lowest concentration(9.51±2..95 pg g^(-1)),and Ba has the highest concentration(3..57±51.3. ng g^(-1)).Notable variations are observed between the pre-1968 AD and post-1968 AD phases for Mn,Zn and *** abrupt,remarkable increase in the concentrations coincided with the change of metal smelting production in the southern *** addition to this,it may also be related to local Antarctic scientific research *** and Fe,the primary crustal elements,are essentially obtained from soil dust;Cu shows high crustal enrichment factors(EFc,>10),indicating that it is notably affected by anthropogenic ***,the anthropogenic activities in the Southern Hemisphere have had an impact on lead deposition in *** study not only enriches the trace metal historical record along the Zhongshan Station-Dome A but also provides a high-resolution ice core record,which is very crucial for the reconstruction of trace metal concentration changes in the last 100 years.

关键词： Eastern Antarctica Ice core Trace metals Human activities

Changes in plant biomass and species composition of alpine Kobresia meadows along altitudinal gradient on the Qinghai-Tibetan Plateau

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Science china(Life sciences) 2008年第1期51卷 86-94页

作者： WANG ChangTing1,3. CAO GuangMin1, WANG QiLan1, jing ZengChun1, ding LuMing1 & LONG RuiJun2.1 Northwest {2. of Plateau Biology, chinese Academy of sciences, Xining 810001, china 2.College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 73.070, china 3.Graduate University of the chinese Academy of sciences, beijing 10003., china 1. Northwest institute of Plateau Biology Chinese Academy of Sciences Xining 810001 China 3. Graduate University of the chinese Academy of sciences Beijing 100039 China 2. College of Pastoral Agriculture Science and Technology Lanzhou University Lanzhou 730070 China

Alpine Kobresia meadows are major vegetation types on the Qinghai-Tibetan Plateau. There is growing concern over their relationships among biodiversity, productivity and environments. Despite the im-portance of species composition, species richness, the type of different growth forms, and plant bio-mass structure for Kobresia meadow ecosystems, few studies have been focused on the relationship between biomass and environmental gradient in the Kobresia meadow plant communities, particularly in relation to soil moisture and edaphic gradients. We measured the plant species composition, her-baceous litter, aboveground and belowground biomass in three Kobresia meadow plant communities in Haibei Alpine Meadow Ecosystem Research Station from 2.01 to 2.04. Community differences in plant species composition were reflected in biomass distribution. The total biomass showed a de-crease from 13.96.96±719.69 g/m2.in the sedge-dominated K. tibetica swamp to 2.69.58±147.52.g/m2.in the forb and sedge dominated K. pygmaea meadow, and to 2.53.08±141.95 g/m2.in the forbs and grasses dominated K. humilis along with the increase of altitude. The vertical distribution of below-ground biomass is distinct in the three meadow communities, and the belowground biomass at the depth of 0-10 cm in K. tibetica swamp meadow was significantly higher than that in K. humilis and K. pygmaea meadows (P1). The herbaceous litter in K. tibetica swamp was significantly higher than those in K. pygnaeca and K. humilis meadows. The effects of plant litter are enhanced when ground water and soil moisture levels are raised. The relative importance of litter and vegetation may vary with soil water availability. In the K. tibetica swamp, total biomass was negatively correlated to species richness (P<0.05); aboveground biomass was positively correlated to soil organic matter, soil moisture, and plant cover (P<0.05); belowground biomass was positively correlated with soil moisture (P<0.05). However, in the K. py

关键词： plant species richness plant litter aboveground biomass belowground biomass soil moisture alpine meadow

The Spatial Database of Digital Geological Map of china at 1:1M

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The Spatial Database of Digital Geological Map of China at 1...

第五届全国地质制图与GIS学术讨论会

作者： ding Xiaozhong~1 HAN Kunying~(1,2. KE Xue~1 JU Yuanjing~1 PANG Jianfeng~1 1,{2. of geology,chinese Academy geology Science,beijing 10003.,china. 2.Faculty of Geosciences and Resources,china University of Geosciences,beijing 100083.{12..

＜正＞The Spatial Database of the Digital Geological Map of china at 1:1 M（V1.0）is made up of 64（whole and partial）map sheets,Each map sheet is represented by the rectangle of 6°longitude and 4°latitude,according to the international map standard at 1:1M,It mainly includes geological map database,geographical map database,metadata database et al,The geological map database is constructed on the basis of the 1:500 000 geological map database（1999）,and it absorbs the latest information and outcomes of 1:2.0 000,1:50000 geological mapping and special subject study,It contains strata,igneous rock,fault,special geological unit（eclogite, blueschist,ophiolite et al.）,isotope age determination and drill hole et al,According to the feature and requirement of the geological map database,the geographical map database was constructed on the basis of 1:1 M topographical map database（ArcInfo） which provided by National Geomatics Center of china,It contains boundaries,river system,inhabitant areas,transportation et al,The Spatial Database of Digital Geological Map of china at 1:1M was built with MapGIS,ArcGIS and Access,The quantity of data is as large as 2.0GB,The spatial database management system possesses functions of map retrieval andquery,automatic map making and automatic legend drawing,The database system will serve on the network in the future,which should be updated and maintained regularly.

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