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“Tali Glaciation” on Massif Diancang

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Science China Earth sciences 2007年第11期50卷 1685-1692页

作者： YANG JianQiang1, CUI ZhiJiu2, YI ChaoLu1, SUN JiMin3.& YANG LiRong3.1 institute of Tibetan Plateau Research, chinese academy of sciences, beijing 100085, China 2 College of Environmental {3., Peking University, beijing 100871, China 3.institute of geology and geophysics, chinese academy of sciences, beijing 10002., China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China College of Environmental sciences Peking University Beijing China institute of geology and geophysics Chinese Academy of Sciences Beijing China

The term of ''Tali Glaciation'' is nominated from Massif Diancang in Yunnan Province. The confusing process of the term''s being put forward is confirmed through literature checking. Based on several times of field trip, the glacial landforms in this region are studied in detail, and the magnitude of the glaciation was determined. According to the numerical ages from TL, AIMS ^(14.C and OSL dating, the earliest glacial advance on Massif Diancang occurred at 3.—4. ka BP, followed by the advances at the last stage of the last glaciation, the late glacial and neoglations in turn, until glaciers vanished at 1.2—1.5 ca. a BP in this region. It can be concluded that glaciers were limited above 3.00 m a.s.l., and no glaciers existed on the lower part and adjacent mountains since the last glaciation.

关键词： Massif Diancang,Tali Glaciation,glacial landform,glaciation sequence,numerical dating

The age of the plant fossil assemblage in the Liuqu Conglomerate of southern Tibet and its tectonic significance

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Progress in Natural Science:Materials International 2006年第1期16卷 55-64页

作者： FANG Aimin1, YAN Zhen1, LIU Xiaohan2, PAN Yusheng1, LI Jiliang1, YU Liangjun1, HUANG Feixing2 and TAO Junrong3.(1.Laboratory of Lithosphere Tectonic Evolution, institute of geology and geophysics,{3.,{4., China 2. institute of Tibet Plateau Research,{3., beijing 100085, China 3. institute of Botany, chinese A cademy of sciences, beijing 100093. China) Laboratory of Lithosphere Tectonic Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China institute of Tibet Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of Botany Chinese A-cademy of Sciences Beijing 100093 China

The Liuqu Conglomerate, situated to the south of Yarlung Tsangbo Suture Zone (YTSZ), is a suit of molasse formed in a foreland basin of the Himalayan orogenic belt after the collision between the two plates of the Indian and Eurasion, It is of great significance in constraining the younger limit time of the collision of the two plates and providing stratigraphic evidence to reveal the post-colli sional tectonic evolution and uplifting history of the Tibet plateau. However, the age of this molasse suit and its correlation to other synchronous strata distributed in southern Tibet have been in great disputes for a long time. Especially in recent years, argues on its ages are growing violently with the recognition of the great sedimentary tectonic significances of this molasse. During the field work carried out recently on this molasse suit, a lot of plant fossils were found preserved in fairly good conditions in the upper part of this strata, which is of great help in determining its age. By identification, the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere supercontinent during the Middle to Later Eocene, which can provide good constraint on its formation age. This paper is to give a brief introduction of the plant assemblage and its age, and to discuss their tectonic significances.

关键词： Liuqu conglomerate plant fossils age Eocene Tectonic implications.

A high-resolution late Pleistocene record of pollen vegetation and climate change from Jingning, NW China

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Science China Earth sciences 2006年第2期49卷 154-162页

作者： LI Chunhai12, TANG Lingyu1, FENG Zhaodong3.4. ZHANG Hucai2, WANG Weiguo3.& AN Chenbang3.1. Nanjing institute of geology and Palaeontology,{3., Nanjing 210008, China 2. Nanjng institute of Geography and Limnology,{3., Nanjing 210008, China 3. Environment and Resources College, Lanzhou University, Lanzhou 73.000, China 4. beijing Normal University, beijing 100875, China Nanjing institute of geology and Palaeontology Chinese Academy of Sciences Nanjing China Nanjng institute of Geography and Limnology Chinese Academy of Sciences Nanjing China Environment and Resources College Lanzhou University Lanzhou China beijing Normal University Beijing China

With the support of 18 AMS-14. data, a high-resolution pollen record from the Suancigou section at Jingning, Gansu Province was established. Our results showed that the vegetation ex-perienced a series of changes characterized by the alternative growth and decline of forest and steppe components during the period from 4..2 to 11 ka B.P. in the Jingning area. Over the period of 4.―29 ka B.P. (MIS3., coniferous forests were flourishing, indicating a humid climate with the tem-perature being lower than that of the present. Since 23.ka B.P., the vegetation was dominated by steppe-desert steppe under a cold and dry condition, and entered the Last Glacial Maximum domi-nated by desert steppe. Several periods of the marked decrease in the arborous pollen content in Suancigou well corresponded to the North Atlantic Heinrich events, especially to Heinrich event 3. further supporting that the Heinrich events were well reflected by the pollen record in the Loess Pla-teau as well.

关键词： Western Loess Plateau, pollen record, climatic change, late Pleistocene.

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science China Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3.1. institute of Geodesy and geophysics, chinese academy of sciences, Wuhan {3.0077, China 2. Graduate School of the chinese academy of sciences, {{3. 10003., China 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 20003., China institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan China Graduate School of the chinese academy of sciences Beijing China Unite Center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Neogene eolian deposits within the West Qinling Mountains:Climatic and tectonic implications

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chinese Science Bulletin 2010年第15期55卷 1483-1487页

作者： GE JunYi 1,2 & GUO ZhengTang 3.1 State Key Laboratory of Loess and Quaternary geology (SKLLQG),institute of Earth Environment,chinese {3. of {4.,Xi’an 710075,China 2 Graduate University of chinese academy of sciences,beijing 10004.,China 3.Key Laboratory of Cenozoic geology and Environment,institute of geology and geophysics,chinese {3. of {4.,beijing 10002.,China State Key Laboratory of Loess and Quaternary geology (SKLLQG) Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of sciences Beijing China Key Laboratory of Cenozoic geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The Qinling Mountains constitute a key climate barrier between southern and northern *** recent investigations revealed widely spread eolian deposits of Neogene age mantling the piedmont highlands of the intermountain basins within West ***-mammalian fossils dated a 150.2 m section (NL-VI) near Xihe for the late Miocene to Pliocene (～10-4.Ma).Soil micromorphology,grain-size and geochemical analysis consistently define typical loess-soil alternations for the upper (0-66 m) and lower (98-150.2 m) parts of the section,with the middle section (66-98 m) having been affected by episodic slope *** results add important insights to the earlier studies about the widespread eolian deposition in northern China during the Miocene,prior to 8 *** also suggest that the basic configuration of the ridges and inter-ridge basins of West Qinling has already formed by ～10 *** well-preserved eolian deposits are unlikely to support intense substratum deformation and rapid uplift of West Qinling since the late Miocene.

关键词：秦岭山脉风尘堆积构造意义气候新近纪晚中新世地球化学分析风尘沉积

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

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Science China(Technological sciences) 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 sciences, {3. 100101, China 2. Geography and Environment College, Jiangxi Normal University, Nanchang 3.0027, China 3. Graduate University of chinese academy of sciences, {3. 10003., China 4. {3. Research institute of Uranium geology, {3. 100875, China 5. institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, {3. 100101, China State Key Laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Geography and Environment College Jiangxi Normal University Nanchang 330027 China Graduate University Chinese Academy of Sciences Beijing 100039 China beijing Research institute of Uranium geology Beijing 100875 China institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 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.

Research progress in studies on the coalbed gas geochemistry

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Progress in Natural Science:Materials International 2006年第3期16卷 215-220页

作者： TAO Mingxin (College of Resources sciences & Technology, beijing Normal University, beijing 100875, China Key Laboratory of Gas Geochemistry, {3. of {4. and geophysics, chinese academy of sciences, Lanzhou 73.000, China) College of Resources sciences and Technology Beijing Normal University Beijing 100875 China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China

The current situation of geochemical studies on coalbed gas is reviewed in this paper. Generally, coalbed gas is composi-tionally dominated by methane with δ13.1 values ranging approximately from - 80‰ to - 10‰. However, few isotopic studies have been carried out on other components of coalbed gas except for hydrogen and carbon dioxide, whose δDCH4.values available for utilization vary from - 3.3. to - 117‰, and δ13.CO2 values from - 29. 4. to + 18. 6‰. Two major types of coalbed gas, thermogenic gas and secondary biogenic gas, have been identified, and there are also some other classification criteria. Compared with conventional natural gases, coalbed gas has a wide distribution range of δ13.1 and δ13.CO2 values, especially possessing some extremely heavy values. Current problems that remain unsolved in the coalbed gas geochemistry include the variation mechanism, controlling factors and application of carbon and hydrogen isotopes of methane, the relation between the values of δ13.1 and Ro, the systematic classification scheme and criterion of genetic types, and the application of the coalbed gas geochemistry in evaluating target districts of the coalbed gas exploration.

关键词： coalbed gas geochemistry isotopic composition genetic type novel resource.

^(4.)Ar-^(3.)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning Region: Age constraints on the Mesozoic tectonic events

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chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch Center of Mineral Resources Exploration, institute of geology and geophysics,{3., {4. 100101, China Guangzhou institute of Geochemistry,{3., Guangzhou 51 Research Center of Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North China, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 4.Ar-3.Ar plateau age of (219±4. Ma (Bi) and two samples from the latter gave 4.Ar-3.Ar plateau ages of (116± 2) Ma (Bi) and (127±3. Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 4.Ar-3.Ar age biotite ductile shear zone West Liaoning Region.

Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles

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Science China Earth sciences 2010年第7期53卷 1071-1078页

作者： ZHAO XiangYu1,2 & LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), institute of geology and geophysics,{3.,{4., China 2 Graduate University of{3., beijing 10004., China Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles.

关键词： Néel theory temperature dependence of susceptibility grain size distribution