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Changes in the content of eolian iron during the past 900 ka and the implications

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Changes in the content of eolian iron during the past 900 ka...

CENOZOIC VOLCANISM AND GEOTHERMAL RESOURCES IN NORTHEAST CHINA

中国科学院地质与地球物理研究所2.03学术年会

作者： WEI Jianjing~1 & GUO Zhengtang~(2.1) 1.institute of Geology and Geophysics,chinese {2. of sciences, Beijing 10002.,China 2.State Key Laboratory of Loess and Quaternary Geology.institute of earth environment.chinese {2. of sciences.xi’an 710075. China

In this study,total FeO content(Fe,) in two parallel sections from the central Loess Plateau(xifeng and Changwu) is analyzed to address the variations of eolian iron in the past 900 *** obtained timeseries indicate that Fet values in some glacial intervals are comparable to that of interglacial periods and its oscillations do not generally correspond to the long-term glacial-interglacial ***, it exhibits higher frequency fluctuations without detectable 100 ka period,but with a strong 2. ka period and a clear 40 ka *** combination of 2. ka and 40 ka periods suggest that eolian iron content was relatively independent of glacial-interglacial changes,but more strongly influenced by the insolation changes in the northern *** iron content was observed for the S5.1 soil that is correlative to marineδO stage *** marine records,this stage is characterized by higherδC values,suggesting that the event is of global significance.

关键词： loess-paleosol sequences eolian iron paleoclimate spectral analysis

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chinese Geographical Science 2001年第2期11卷 150-154页

作者： WANG xi-kui1, QIU Shan-wen2. SONG Chang-chun2. KULAKOV Aleksey3, TASHCHI Stepan3, MYASNIKOV Evgeny3 (1.College of earth sciences, Jilin University,Changchun 130012.P.R.China 2.Changchun {2. of Geography, the chinese academy of sciences,Changchun College of earth sciences Jilin University Changchun P. R. China Changchun institute of Geography the Chinese Academy of Sciences Changchun P. R. China Pacific institute of Geography Far East Science Center of the Russian Academy of Sciences Vladivostok Russia

This paper is concentrated on Cenozoic volcanism and geothermal resources in Northeast China. There are a lot of Cenozoic volcanoes, a large area of volcanic rocks, a large number of active faults and rich geothermal resources in Northeast China. The time and space characteristics of Cenozoic volcanism and the space distribution characters of hot springs and high geothermal flux regions in Northeast China are described and discussed on the basis of geological, geothermal, drilling and volcanological data. It is revealed that the hot springs and high geothermal flux regions are related to the Cenozoic volcanism, rifting and faulting in Northeast China. It is especially emphasized that the hot springs and high geothermal anomaly areas are controlled by active deep faults. It is proposed that the Cenozoic volcanism regions, rift basins, active fault belts, activated plate suture zones and large earthquake occurrence points are the best areas for prospecting geothermal resources. The geothermal resources in younger volcanic zones are richer than those in older volcanic belts. The hot springs and active or activated faults might be a very good clue for looking for geothermal resources.

关键词： volcanism active faults geothermal resources Northeast China

Eolian origin of the Miocene loess-soil sequence at Qin'an,China:evidence of quartz morphology and quartz grain-size

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Eolian origin of the Miocene loess-soil sequence at Qin'an,C...

Lithosphere types in North China:Evidence from geology and geophysics

中国科学院地质与地球物理研究所2.06学术年会

作者： LIU Jinfeng~1,GUO Zhengtang~(2.1),QIAO Yansong~(3,1),HAO Qingzheng~1 & YUAN Baoyin~1 institute of Geology and Geophysics,chinese {2. of sciences,Beijing 10002.,China 2.SKLLQG,institute of earth environment,chinese {2. of sciences,xi’an 710075.China 3.institute of Geomechanics,chinese {2. of Geological sciences,Beijing 100081,China

Grain-morphology and grain-size distributions of the quartz fraction from the QA-I loess-soil sequence are examined,and compared with those of the typical eolian deposits of Quaternary age from the xifeng *** of the quartz grains from QA-I section have irregular and angular shapes which are highly similar to those of the xifeng Quaternary eolian samples,and also to those of the Quaternary and Pliocene eolian deposits ***-size analyses show that the quartz fraction is dominated by the silt fraction5.μm,and mostly smaller than 12.μm. These features are characteristic of eolian dust ***-size analyses on both quartz and bulk samples consistently indicate a pattern of coarser grain-size in loess and finer grain-size in soils,also similar to that of the Quaternary loess-soil *** suggest that the Miocene paleosols are accretionary soils formed in monsoon *** quartz morphological features and grain-size distributions therefore provide new evidence of an eolian origin of the Qin’an Miocene sequences.

关键词： Miocene loess-paleosol sequence quartz grain scanning electron microscopy grain size

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Science China earth sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2. DENG Jinfu3, ZHOU Su3, LI Jinfa4, xiAO Qinghui1,5. WU Zongxu6 & LIU Cui3 1. institute of Geology, chinese {2. of Geological {5., Beijing 100037, China 2. Development and Research Center, China Geological Survey, Beijing 100037, China 3. China University of Geo{5., Beijing 100083, China 4. China University of Geo{5., Wuhan 430074, China 5. Information Center of Ministry of Land and Resources, Beijing 100812. China 6. institute of Geology, State Seismological Bureau, Beijing 10002., China 1. institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. China University of Geosciences 100083 Beijing China 4. China University of Geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North China, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North China platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North China Platform is a remnant of cratonic lithosphere after the North China platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North China craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North China platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North China in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

TAKE ANOTHER VISION TO THE UPLIFT OF THE QING—ZANG (TIBETAN) PLATEAU BASED ON CENOZOIC VOLCANISM

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地学前缘 2000年第S1期7卷 370-371页

作者： Liu Jiaqi [WT5.5.BX](institute of Geology and Geophysics,chinese {2. of sciences,Beijing 10002., China)

The emergence of the Qing—Zang plateau is among the most important geological events on the globe since the Cenozoic Era. Many geological issues can find answer from here. The major issues concerning plateau probably have three: (1) geodynamics, timing and speed of the plateau uplift;(2. The plateau uplift impact on surrounding environment;(3) mineral resources in the plateau. The authors want to focuses on first issue based on volcanisms occurred in interior and surrounding of the plateau, The new opinions are following:(1) Each volcanic eruptive episode corresponded to strong uplift stage;(2. The dynamic mechanism of the plateau uplift can not ignore another force from west beyond collision between Indian and Eurasia plates from South;(3) The surrounding volcanic chain is not only related to the collision from South, but also from west.

关键词： Tibetan plateau the Cenozoic volcanism volcanic chain surro unding plateau west collision uplift mechanism

Plausible impact of global climate change on water resources in the Tarim River Basin

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Science China earth sciences 2005年第1期48卷 65-73页

作者： CHEN Yaning & XU Zongxue xinjiang institute of Ecology & Geography, chinese academy of sciences, Urumqi 830011, China College of {2.al sciences, Beijing Normal University, Beijing 100875. China 1. xinjiang institute of Ecology & Geography Chinese Academy of Sciences 830011 Urumqi China 2. College of environmental sciences Beijing Normal University 100875 Beijing China

Combining the temperature and precipitation data from 77 climatological stations and the climatic and hydrological change data from three headstreams of the Tarim River: Hotan, Yarkant, and Aksu in the study area, the plausible association between climate change and the variability of water resources in the Tarim River Basin in recent years was investigated, the long-term trend of the hydrological time series including temperature, precipitation, and streamflow was detected, and the possible association between the El Ni(n)o/Southern Oscillation (ENSO) and these three kinds of time series was tested. The results obtained in this study show that during the past years, the temperature experienced a significant monotonic increase at the speed of 5., nearly 1℃ rise; the precipitation showed a significant decrease in the 1970s, and a significant increase in the1980s and 1990s, the average annual precipitation was increased with the magnitude of 6.8 mm per decade. A step change occurred in both temperature and precipitation time series around 1986, which may be influenced by the global climate change. Climate change resulted in the increase of the streamflow at the headwater of the Tarim River, but the anthropogenic activities such as over-depletion of the surface water resulted in the decrease of the streamflow at the lower reaches of the Tarim River. The study result also showed that there is no significant association between the ENSO and the temperature, precipitation and streamflow.

关键词： climate change, hydrological change, temperature, precipitation, streamflow, Tarim River.

Characterization of Primary and Secondary Carbonaceous Aerosols in xi’an,China

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Characterization of Primary and Secondary Carbonaceous Aeros...

Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

第七届海峡两岸气胶技术研讨会暨第二届空气污染技术研讨会

作者： Suixin Liu1 Zhuzi Zhao1 Junji Cao2.Zhenxing Shen3 1.SKLLQG institute of earth {2. chinese academy of sciences xi’an China Graduate School of the chinese academy of sciences Beijing China 2.SKLLQG institute of earth {2. chinese academy of sciences xi’an China 3.Department of {2.al Science and Engineering xi’an Jiaotong University China

＜正＞INTRODUCTION As a major component of atmospheric particulate matter （PM）,carbonaceous material plays an important role in visibility reduction,radiative forcing,and adverse human health effects1～4. Carbonaceo... 详细信息

关键词： time-resolved EC tracer method secondary organic aerosol

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Science China earth sciences 2011年第4期54卷 493-508页

作者： xiAO Liang 1,2.3,4,SUN BaiNian 1,2.,LI xiangChuan 1,REN Wenxiu 1 &JIA Hui 1 1 Key Laboratory of Western China's {5.al Systems of the Ministry of Education and College of earth and {5. Science,Lanzhou University,Lanzhou 730000,China 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,chinese academy of sciences,Nanjing 2.0008,China 3 College of Arts and sciences,Bryant University,Smithfield RI 02.17,U.S.A. 4 Key Laboratory of Western China's Mineral Resources and Geological Engineering of Ministry of Education,Chang’an University,xi’an 71005.,China 1. Key Laboratory of Western China’s environmental Systems of the Ministry of Education and College of earth and environment Science Lanzhou University Lanzhou 730000 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China3. College of Arts and Sciences Bryant University Smithfield RI 02917 USA4. Key Laboratory of Western China’s Mineral Resources and Geological Engineering of Ministry of Education Chang’an University Xi’an 710054 China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene xiannanshan Formation,Zhejiang Province(eastern China) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(5.%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene xiananshan Formation sun and shade leaves

FORMATION AND EUOLUTION OF TETHYS IN THE TIBETAN PLATEAU

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地学前缘 2000年第S1期7卷 334-335页

作者： Pan Yusheng[WT5.5.BX](institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002.,China)

The formation of the Tibetan Plateau is closely related to the evolution of Tethys. There have been many researchers and articles concerning the Tethys since *** proposed the concept in 1893. It means a large ocean which lies between Eurasia and Gondwanaland. With the development of Tethyan research, some new terms, appeared such as Neo\|Tethys, Paleo\|Tethys, and Proto\|Tethys, representing the Tethys in Mesozoic—Cenozoic, late Paleozoic and early Paleozoic respectively. The trace of an ocean from Sinian to Ordovician was discovered during the scientific expedition and Proto\|Tethys was proposed to name the ocean. Therefore, the Tibetan Plateau is the main scope of the Eastern Tethys. It can be divided c losely related into three zones which represent the main oceanic locations in th ree different *** Northern Tethyan Region lies in the Kunlun and Qilian Mountains, its remnant is the Fifth Suture Zone. It is also the northern boundary of the Tibetan Plateau The rift initiated after the continental basement had been formed in Sinian and gradually developed into an ocean, which was named Proto\|Tethys, the earliest Tethyan ocean known up to now. The petrochemical compositions of pillow lava in this zone show the characteristics of mid\|ocean ridge tholeiite basalt and the pelagic ophiolitic flysch were well developed, indicating a matured ocean. It was closed in Ordovician and Silurian.

关键词： formation and evolution Tethys Tibetan plateau suture zone structural deformation Gondwana land