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Sporopollen analysis of Core B1. 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.{2. 2. institute of Oceanology, Chinese academy of sciences, Qingdao 2.6071.{2. 3. Graduate School, Chinese academy of sciences, beijing 100039.{2. 1. Key Laboratory of Marine Sedimentology and Environmental geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. {1. 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 B1. in the southern Yellow Sea. Based on the results along with ^1.C 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1.年代测定底基压型数据更新世沉积环境大西洋

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Implications of micro-compositions of garnet and biotite from high-grade meta-pelites

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Progress in Natural Science:Materials International 2006年第2期16卷 209-214页

作者： ZHOU Xiwen, WEI Chunjing, and ZHANG Shangkun ( institute of {1., CAGS,{2., china School of Earth and Space sciences, Peking University, beijing 1.0871. china china University of Geo-sciences, beijing 1.0083, china) institute of {1. CAGS Beijing 100037 China School of Earth and Space sciences Peking University Beijing 100871 China china University of Geo-{1. Beijing 100083 China

Based on detailed studies on the compositional zoning of garnet and biotite in pelitic rocks from the Jingshan group of granulite facies in north Jiaodong, P-T pseudosections with isopleths of Fe/(Fe + Mg) in garnet and biotite were calculated in the KF-MASH system for two representative rocks of sillimanite-garnet-cordierite-biotite gneiss ( Vbi/ Vg>1.) and sillimanite-garnet gneiss (Vbi/ Vg2. using the software THERMOCALC and the internally consistent thermodynamic dataset. With a comparison of the calculated Fe/(Fe+ Mg) values in garnet and biotite in the peak P-T fields constrained by peak mineral assemblages with the measured ones, it is concluded that the coarse garnet crystals with diffusion zoning from high grade meta-pelites can preserve their peak compositions even when they have experienced a cooling event, and that biotite crystals surrounded by fetsic minerals in biotite-rich rocks with Vbi/Vg> 1.can nearly preserve their peak compositions, and biotites in garnet-rich rocks with Vbi/Vg2.cannot preserve their peak compositions due to the influence of grain-boundary fluid.

关键词： high-grade meta-pelites THERMOCALC P-T pseudosection peak compositions of garnet and biotite.

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Deep seismic reflection profiling revealing the complex crustal structure of the Tongling ore district

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Science china Earth {1. 2004年第3期47卷 193-200页

作者： L5 Qingtian1. HOU Zengqian1. ZHAO Jinhua1. SHI Danian1. WU Xuanzhi1. CHANG Yinfo1. PEI Rongfu1.HUANG Dongding2.& KUANG Chaoyang2.1. institute of Mineral Resources, Chinese academy of {2. sciences, beijing 100037, china 2. The Sixth Geophysical Exploration Brigade, Petroleum Bureau of East china, Nanjing 2.0009, china Chinese Acad Geol Sci Inst Mineral Resources Beijing 100037 Peoples R China Petr Bur E china Geophys Explorat Brigade 6 Nanjing 210009 Peoples R China

The deep seismic profiling across the Tongling ore district reveals a complex crustal structure. Strong contrasting dipping layered reflections (4—1. s, TWT),which dominate the lower crust of the northern part of the profile, are interpreted as the underplating of the basalt related to extensional tectonism. In the south of the profile, the Yangtze craton is characterized by strong reflections in the middle crust, showing a distinct two-layer crustal structure. Over the region of the Tongling uplift, there appear the complex arc shape reflections, suggesting folded, faulted and intruded structures, and the transparent zone below them reveals the existence of batholith. The south dipping strong reflections between the upper crust and lower crust (4—7 s, TWT) suggest a detachment between them. The detachment provided space for the magma intrusion, and caused the formation of the batholith. The Yangtze craton has a clear Moho re-flection, while the Tongling uplift has a weak Moho, whereas below the reflective lower crust in the northern part of the profile, there are sub-Moho reflections. The abrupt variation of the Moho characteristics within a short distance indicates the complexity of magmatic activity.

关键词： metallogenic belt, ore district, deep seismic profiling, crustal structure.

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Control of atmospheric CO_2.concentrations by 2.50: A calculation on the emission rights of different countries

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Science china Earth {1. 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1. DUAN XiaoNan2. GE QuanSheng3 & ZHANG ZhiQiang4 1.{1. of geology and Geophysics, Chinese {2. of sciences, beijing 1.002., china 2.The General Office of Chinese {2. of sciences, beijing 1.0864, china 3 {1. of Geographic sciences and Natural Resources Research, Chinese {2. of sciences, beijing 1.01.1. china 4 The Lanzhou Branch of the National Science Library, the Scientific Information Center for Resources and Environment, Lanzhou 730000, china institute of {1. and Geophysics Chinese Academy of Sciences Beijing 100029 China The General Office of Chinese academy of {1. Beijing 100864 China institute of Geographic {1. 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 1.00 to 2.05, and their annual emissions allowances into the future (2.06―2.50), a 470 ppmv atmospheric CO2.concentration target was set. According to the following four objective indicators―total emissions allowance from 1.00 to 2.50, actual emissions from 1.00 to 2.05, emissions levels in 2.05, and the average growth rate of emissions from 1.96 to 2.05―all countries and regions whose population was more than 300000 in 2.05 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 2.05 had already expended their 2.50 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (2. dollars per ton of CO2.. Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2.06 to 2.50 would still be much higher than those of developing coun

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

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Biomass estimation and uncertainty analysis based on CBERS-02.CCD camera data and field measurement

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Science china(Technological {1.) 2005年第S2期48卷 116-128页

作者： CHEN Liangfu1,2. GAO Yanhua1,3, CHENG Yu1,3, WEI Zheng1,3, XIAO Qing1,4, LIU Qinhuo1, YU Tao1, LIU Qijing5, GU Xingfa1 & TIAN Guoliang1 1. State Key Laboratory of Remote Sensing Science, institute of Remote Sensing Applications, Chinese academy of {2., beijing 100101, china 2. Geography and Environment College, Jiangxi Normal University, Nanchang 33002., china 3. Graduate University of Chinese academy of {2., beijing 100039, china 4. beijing Research institute of Uranium {12., beijing 100875, china 5. institute of Geographic {2. and Natural Resources Research, Chinese academy of {2., beijing 100101, china 1. State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences 100101 Beijing China 2. Geography and Environment College Jiangxi Normal University 330027 Nanchang China 3. Graduate University of Chinese academy of {1. 100039 Beijing China 4. beijing Research {1. of Uranium {2. 100875 Beijing China 5. institute of Geographic {1. and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China

The study site is located in Qianyanzhou experimental station and the surrounding area. Based on CBERS-02.satellite data and field measurement, we not only discussed the relationship between NDVI and biomass of two species of coniferous plantations, namely, Pinus massoniana Lamb and Pinus elliottii Engelm, but also introduced the biomass models based on NDVI. The comparison between measured biomass in Qianyanzhou and biomass derived from CBERS-02.CCD data showed that it is feasible to estimate biomass based on NDVI. But its limitations cannot be ignored. This kind of model depends on the dominant vegetation species. There are some effect factors in estimating biomass based on NDVI. This paper analyzes these factors based on fine-resolution CBERS-02.CCD data and some conclusions are drawn: In Qianyanzhou, the area with good vegetation coverage, the nonlinearity of NDVI has little influence on scaling-up of NDVI. As a result of surface heterogeneity, scaling-up can cause NDVI within each pixel to change. Because scaling-up can cause pixel attribute to change, the applicability of biomass model is one of the sources of error in estimating biomass.

关键词： NDVI biomass scaling effect scaling-up.

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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Science china Earth {1. 2006年第3期49卷 225-241页

作者： ZUO Jingxun1.2. TONG Jinnan3, QIU Haiou4 & ZHAO Laishi3 1. Nanjing {1. of geology and Palaeontology, Chinese {2. of sciences, Nanjing 2.0008, china 2. Henan {1. of geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of geological Processes and Mineral Resources at china University of Geosciences, Wuhan 430074, china 4. Faculty of Material sciences and Chemical Engineering, china University of Geosciences, Wuhan 430074, china 1. Nanjing institute of {1. and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan {1. of geological Survey Zhengzhou 450007 China 3. State Key Laboratory of geological Processes and Mineral Resources at{1. University of Geo{2. Wuhan 430074 China 4. Faculty of Material sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 1.C background values are intensively controlled by palaeogeographic environment. In general, δ 1.C values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Average slip rate, earthquake rupturing segmentation and recurrence behavior on the Litang fault zone, western Sichuan Province, china

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Science china Earth {1. 2005年第8期48卷 1183-1196页

作者： XU Xiwei1. WEN Xueze2. YU Guihua1. ZHENG Rongzhang1. LUO Haiyuan2.& ZHENG Bin2.1. institute of geology,{2. Earthquake Administration, beijing 1.002.,{2. 2. Earthquake Administration of Sichuan Province, Chengdu 61.041.{2. 1. institute of {1. China Earthquake Administration 100029 Beijing China 2. Earthquake Administration of Sichuan Province 610041 Chengdu China

The Litang fault zone (LFZ) is an active fault zone within the northwestern Sichuan sub-block. Field investigation reveals new evidence for its late Quaternary offset, neoteric earthquake ruptures and surface-rupturing segmentation, from which long-term slip-rates, char-acteristic earthquake magnitudes and recurrence intervals on the fault zone are estimated. This study shows that the LFZ consists of three subordinate faults, and they are the northern Maoyaba fault, Litang fault and Kangga-Dewu fault, respectively. All of them are dominated by left-lateral strike-slip with reverse dip-slip component on different segments. Based on offset landforms and ages of relevant deposits collected from seven sites, it is estimated that the average left-lateral slip-rate on the LFZ reaches 4.0±1.0 mm/a in the past 1. ka BP, and vertical (reverse) dip-slip rate in the range of 0.1.1.8 mm/a. Three subordinate faults are independent earthquake rup-turing segments, on which the maximum moment magnitude of the characteristic earthquakes is estimated to be 7.0―7.3, and their average recurrence interval to be 500―1.00 a. The latest earthquake ruptures occurred 1.9±2.years ago on the northern Maoyaba fault, about 1.90 AD on the Litang fault, and in 1.48 AD on the Kangga-Dewu fault, and this may indicate a unidirectional migration for surface rupturing earthquakes along the Litang fault zone, related to stress trigger-ing between the segments.

关键词： Litang fault zone, slip rate, earthquake rupturing segmentation, recurrence interval.

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Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,china

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Chinese Science Bulletin 2001年第13期46卷 1112-1117页

作者： WANG Xiaolin & LU Junchang1. institute of Vertebrate Paleontology and Paleoanthropology, Chinese academy of {2., beijing 100044, china 2. College of Earth {2. and Resources, china University of Geo-{2., beijing 100083, china 3. Department of geological {2., Southern Methodist University, Dallas, TX 752.5, USA institute of Vertebrate Paleontology Chinese Academy of Sciences Beijing 100044 China

A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution and

关键词： western Liaoning Early Cretaceous Yixian Formation Pterodactylidae.

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Two new species of Vestrogothia (Phosphatocopina, Crustacea) of Orsten-type preservation from the Upper Cambrian in western Hunan, South china

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Science china Earth {1. 2009年第6期52卷 784-796页

作者： ZHANG HuaQiao1.2.& DONG XiPing1.2.1.School of Earth and Space sciences,Peking University,beijing 1.0871.{2. 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of geology and Palaeontology,Chinese academy of sciences,Nanjing 2.0008,{2. School of Earth and Space sciences Peking University Beijing 100871 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in {1.05, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

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Regulation mechanism of EM parameters in natural ferrite and its application in microwave absorbing materials

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Science china(Technological {1.) 2006年第1期49卷 38-49页

作者： ZHENG Yongchun1,2. WANG Shijie2. FENG Junming2. LI Chunlai1, OUYANG Ziyuan1,2. LIU Jianzhong1 & LI Xiaobiao2.1. National Astronomical Observatories, Chinese academy of sciences, {2. 100012. china 2. State Key Laboratory of Environmental Geochemistry, institute of Geochemistry, Chinese academy of sciences, Guiyang 550002. china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China 2. State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Electromagnetic (EM) parameters (ε ′, ε ″, μ ′, μ″ ) of several M2.Fe2.4 and Fe2.3 type natural ferrites with different geological occurrences are measured in this pa-per. The measurement results show that EM parameters of a magmatic-occurring natural ferrite is very different from other types occurring from sedimentary-metamorphic iron deposit, hydrothermal vein iron deposit, outer contact of magmatic iron deposit. It has potential to be used as magnetic absorbent in microwave absorbing materials. After min-eral separation and concentration, this magmatic-occurring natural ferrite was processed into type A ferrite absorbent. Type A natural ferrite absorbent is a kind of magnetic material with low dielectric constants, high magnetic conductivity and high EM loss. Its EM pa-rameters are ε ′ = 58.60, ε ″ = 1..0, μ ′ = 1.2.1.5, μ ″ = 1.0-1.2. respectively. In order to illuminate the regulation mechanism of EM parameters, we studied the chemical and mineral composition of type A ferrite absorbent. There is high concentration of natural impurities, which regulate the EM parameters of type A ferrite greatly. For comparison, the other types of natural ferrite, single-phase magnetite and two-phase iron minerals (ilmen-ite and magnetite), have few impurity. Thus regulation mechanism of EM parameters was absent in these ferrites. As a result, the regulation of EM parameters is advantageous to develop type A natural ferrite as excellent absorbent, lowers the reflectivity coefficients and enhances the absorbing efficiency of MAM made from it. Furthermore, the impurities in type A natural ferrite and its effects on EM parameters are very difficult to simulate in the synthesize ferrite. The carbonyl-iron powder is another kind of absorbent that is used ex-tensively in MAM. To compare the absorbing properties of these two absorbent, type A natural ferrite and carbonyl-iron powder were mixed with rubber and processed into mi-crowave absorbing sheets with the same procedures and tec

关键词： natural impure ferrite, complex permittivity, complex permeability, microwave absorbing materials.

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