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Origin of the Red Earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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Science China Earth Sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4. HUANG Baochun5 & LI Zhen6 1. SKLLQG, institute of Earth Environment, chinese {2. of Sciences, Xi’an 710075, China 2. Department of Urban and Resources Sciences, Nanjing University, Nanjing 2.0093, China 3. Department of Earth Sciences, Nanjing University, Nanjing 2.0093, China 4. Department of Geography, Shaanxi Normal University, Xi’an 710062. China 5. institute of geology and Geophysics, chinese {2. of Sciences, beijing 10002., China 6 Department of Geography, Qinghai Normal University, Xining 810008, China 7. Graduate School of the chinese {2. of Sciences, beijing 100039, China SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate School of the chinese academy of Sciences Beijing China Department of Urban and Resources Sciences Nanjing University Nanjing China Department of Earth Sciences Nanjing University Nanjing China Department of Geography Shaanxi Normal University Xi’an China institute of geology and Geophysics Chinese Academy of Sciences Beijing China Department of Geography Qinghai Normal University Xining China

The Red Earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red Earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the chineseLoess Plateau. Grain-size analysis shows that the Red Earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red Earth *** REE distributions of the loess-soil and the Red Earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red Earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the RedEarth deposition predates 11.4.Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red Earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red Earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

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Cosmogenic ^(2.)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science China Earth Sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2.DING Lin2.LAI QingZhou2.& HUANG FeiXin3 1 Key Laboratory of the Earth’s Deep Interior,institute of {4. and Geophysics,{2. academy of Sciences,beijing 10002.,China 2.Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,{2. academy of Sciences,beijing 100085,China 3 institute of Mineral Resources Research,China Metallurgical {4. Bureau,beijing 10002.,China Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of Mineral Resources Research China Metallurgical Geology Bureau Beijing China

Various sources of 2.Ne and 2.Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in China,of cosmogenic 2.Ne and 2.Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 2.Ne and ***-heating experiments show that concen-trations of cosmogenic 2.Ne and 2.Ne in summit bedrock samples R92.2.and R92.3 from Grove Mountains,Antarctica,are(3.83±0.87)×108 and(5.2.±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2.0.5 and 3.0±0.3 *** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 2.Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

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Megaclasts from the Carboniferous-Permian Rocks in the Langkawi Islands, Malaysia, and Their Implications

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Acta Geologica Sinica(English Edition) 1999年第1期73卷 120-122页

作者： Chen Tingyu institute of geology 2. Baiwanzhuang Road,{2. {4. of Geological Sciences, beijing 100037,China chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

The Ninth Regional Congress on geology, Mineral andEnergy Resources of Southeast Asia was held in KualaLumpur of Malaysia in August of 1998. After the Con-gress, the author participated in the geological fieldexcursion and investigation in the Langkawi Islands,and noted that the Carboniferous-Permian rocks con-tain megaclasts of metamorphic and pegmatitic rocks,which indicate the existence of pre-Carboniferousmetamorphism and magmatism. The observation resultsare as follows:

关键词： Malaysia and Their Implications Megaclasts from the Carboniferous-Permian Rocks in the Langkawi Islands

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Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and Early Jurassic Lower Yimen Formation, Sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： Liu Junying Chen Zhongliang institute of geology, {2. academy of Geological Sciences, {4. Panxi Geological Party, Sichuan Bureau of geology and Mineral Resources, Xichang Liu Linqun institute of geology Chinese Academy of Geological Sciences Beijing China

This paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand Early Jurassic Lower Yimen Formation in Xichang, Sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the Early Jurassic, have been rarelypublished. The description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern China but reveals for the first time the features of the charophyte flora of the Late Triassic-EarlyJurassic in the area, thus offering valuable data for the establishment of Triassic and Jurassic charophyte fossilzones in China.

关键词： Sichuan Late Triassic Early Jurassic charophyte fossil

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Liaoxiornis delicatus *** ***.,the smallest Mesozoic bird

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chinese Science Bulletin 1999年第9期44卷 834-838页

作者： HOU Lianhai and CHEN Peiji institute of Vertebrate Paleontology and Paleoanthropology, chinese {2. of Sciences , beijing 10004., China Nanjing institute of geology and Paleontology, chinese {2. of Sciences , China institute of Vertebra Paleontology und Paleoanthropology Chinese Academy of Sciences Beijing China Nanjing Instittue of Gology and Paleontology Chinese Academy of Sciences China

Recently, a very small and complete bird specimen was collected from the Confuciusornis-bearing Yixian Formation. This finding represents a new kind of Mesozoic bird, named Liaoxiornis delicatus. It is characterized by a short skull with teeth, a long neck and a very small sternum with only posterior process; the humeral head is not internally curved, and the hindlimbs are longer than the forelimbs. Liaoxiomis delicatus is not only much smaller than Confuciusornis, but also smaller than Cathayomis and other early Cretaceous birds. It is the smallest bird known from Mesozoic deposit. Liaoxiornis provides new evidence indicating that the early adaptive radiation of birds is complicated.

关键词： Mesozoic early bird evolution of birds.

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Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

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Progress in Natural Science:Materials International 2007年第3期17卷 305-313页

作者： YAN Zhen, YU Liangjun, LI Jiliang, BIAN Qiantao, WANG Zongqi and YANG Yongcheng ( institute of geology, {2. academy of Geological Sciences, {4. 100037, China State Key Laboratory of Lithospheric Evolution, institute of geology and Geophysics, {2. academy of Sciences, beijing 10002., China Shaanxi Insititute of geology Survey, Xianyang 712.00, China) institute of geology Chinese Academy of Geological Sciences Beijing 100037 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Shaanxi Insititute of geology Survey Xianyang 712000 China

The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy, and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.

关键词： Middle-Upper Triassic fluvial-lake environments tide environment tempestite Songpan-Ruoergai

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Variations of δ^(18)O in precipitation from the Muztagata Glacier, East Pamirs

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Science China Earth Sciences 2006年第1期49卷 36-42页

作者： LI Zhen1, YAO Tandong1,2. TIAN Lide1,2. XU Baiqing1,2.& wu Guangjian2.1. Key Laboratory of Cryosphere and Environment, Jointly Established by Cold and Arid Regions Environmental and Engi-neering Research institute and institute of Tibetan Plateau Research, chinese academy of Sciences and chinese academy of Meteorological Sciences, China Meteorological Administration, CAS, Lanzhou 730000, China 2. Laboratory of Environment and Process on Tibetan Plateau, institute of Tibetan Plateau Research, chinese academy of Sciences, beijing 100085, China Key Laboratory of Cryosphere and Environment Jointly Established by Cold and Arid Regions Environmental and Engineering Research Institute and Institute of Tibetan Plateau Research Chinese Academy of Sciences and Chinese Academy of Meteorological Sciences China Meteorological Administration Lanzhou China Laboratory of Environment and Process on Tibetan Plateau Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Expeditions to Muztagata (in the eastern Pamirs) during the summer seasons of2.02.and 2.03 collected precipitation samples and measured their oxygen isotopes. The δ^(18)O inprecipitation displays a wide range, varying from -17.4.per thousand to +1.33per thousand inJune—September 2.02.and from -2..31per thousand to +4.59per thousand in May—August 2.03. Theδ^(18)O in precipitation correlates with the initial temperature of precipitation during theobserving periods. The positive correlation between δ^(18)O and temperature suggests that δ^(18)Ocan be used as an indicator of temperature in this region. The δ^(18)O values in fresh-snow samplescollected from two snow events at different elevations on the Muztagata Glacier show a strong''altitude effect'', with a ratio of nearly -0.4.per thousand per 100 m from 5500 m to 74.0 m.

关键词： Muztagata, δ18O, temperature, altitude effect.

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CMQV+:An authenticated key exchange protocol from CMQV

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Science China(Information Sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2.& wu ChuanKun 1 1 State Key Laboratory of Information Security,institute of Software,{2. {4. of Sciences,beijing 100190,China 2.Graduate University of {2. {4. of Sciences,beijing 10004.,China State Key Laboratory of Information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption

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A Study of Mesoproterozoic Iron Cosmic Micro-spherules from 1.8 Ga and 1.6 Ga Old Strata in the Ming Tombs District,beijing

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 649-657页

作者： SONG Tianrui HE Zhengjun WAN Yusheng and LIU Yanxue institute of geology,{2. academy of Geological Sciences,{4. 100037 chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

Numerous iron cosmic micro-spherules have been discovered from Mesoproterozoic strata including the Changzhougou Formation （1.8 Ga） and the Dahongyu Formation （1.6 Ga） of the Ming Tombs district, beijing. There are 1 to 30 grains of cosmic spherules per 2.kg of a sandstone sample taken from the bottom of a coarse sandstone bed of the Changzhougou Formation and 56 grains per 3.69 kg of a rock sample from silicified carbonate rocks of the Dahongyu Formation. The surface textures of cosmic spherules analyzed by means of the secondary electron imagery are identical with those reported from references either domestic or abroad. So far the geo-ages of 1.8 Ga and 1.6 Ga of cosmic spherules from the Changzhougou and Dahongyu formations might be older than those reported in the world. Table 1 gives the electron probe analysis data of cosmic spherules for 30 spherule grains and 4. testing points as follows （%）： FeO, 80-95; Cr2.3; 0-9.56; NiO, 0-0.78; CoO, 0-0.4.; indicating that the Cr2.3 content is higher and FeO content lower in the Changzhougou Formation than in the Dahongyu Formation. The helium isotopic data of cosmic spherules as well as their host rocks vary greatly between the Changzhougou and the Dahongyu formations as shown in Table 2. The data of cosmic spherules of the Changzhougou Formation vs the Dahongyu Formation are 57.5/1.2. in ^3He/^4.e （10^-8）; and 55.54.809.60 in ^4.e （10^-6cm^3STP/g）; those of coarse sandstone of the Changzhougou Formation vs silicified carbonate of the Dahongyu Formation are 3.39/2.59 in ^3He/^4.e （10^-8） and 4.56/2.34.in ^3He （10^-6cm^3STP/g）. The ratio of analytic data of helium isotopes are different for cosmic spherules and their host rocks; for example, the ^3He/^4.e （10^-8） values are 16.96 and 0.4., and the ^4.e （10^-6 cm^3STP/g） are 12.18 and 34..98 for the Changzhougou and Dahongyu formations respectively. It was reported that the world＇s oldest micrometeorites had been found in the Meso-Proterozoic Satakunta Formation, Finland

关键词： Proterozoic cosmic spherule helium isotopes extraterrestrial material carbonaceous chondrite

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The principle of relativity, kinematics and algebraic relations

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 591-597页

作者： GUO HanYing1, HUANG ChaoGuang2.3, wu HongTu4.& ZHOU Bin5 1institute of Theoretical Physics, {2. {4. of Sciences, beijing 100190, China 2.1} of High Energy Physics, {2. {4. of Sciences, beijing 10004., China 3Theoretical Physics Center for Science Facilities, {2. {4. of Sciences, beijing 10004., China 4.epartment of Mathematics, Capital Normal University, beijing 10004., China 5Department of Physics, beijing Normal University, beijing 100875, China institute of Theoretical Physics Chinese Academy of Sciences Beijing China institute of High Energy Physics Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing China Department of Mathematics Capital Normal University Beijing China Department of Physics Beijing Normal University Beijing China

Based on the relativistic principle and the postulate of universal invariant constants (c, l), all kinematic symmetries can be set up as the subsets of the Umov-Weyl-Fock-Hua transformations for the inertial motions. ... 详细信息

关键词： principle of relativity with (c l) Umov-Weyl-Fock-Hua transformations kinematics special relativity triple

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