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Late Cenozoic high-resolution magnetostratigraphy in the Kunlun Pass Basin and its implications for the uplift of the northern Tibetan Plateau

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Science Bulletin 2005年第17期 98-108页

作者： SONG Chunhui1, GAO Dongling1,2. FANG Xiaomin3,1, CUI Zhijiu4. LI Jijun1, YANG Shengli3, JIN Hongbo1, Douglas Burbank5 & Joseph L. Kirschvink6 1. MOE Key Laboratory of Western China’s Environmental Systems (Lanzhou University), Ministry of Education & College of Earth and Environment Sciences, Lanzhou University, Lanzhou 730000, China 2. Qinghai institute of Salt Lakes, Chinese Academy of Sciences, Qing-hai 810008, China 3. institute of Tibetan Plateau Research, Chinese Academy of Sciences,{2., China 4. College of Environmental Sciences, Peking University, beijing 100871, China 5. Department of Geological Sciences, University of California, Santa Barbara, USA 6. Paleomagnetics Laboratory, Division of Geological and Planetary Sciences, California institute of Technology, Pasadena, CA 9112., USA

The Kunlun Pass Basin, located in the middle of the eastern Kunlun Mountains, received relatively con-tinuous late Cenozoic sediments from the surrounding mountains, archiving great information to understand the deformation and uplift histories of the northern Tibetan Pla-teau. The Kunlun-Yellow River Movement, identified from the tectonomorphologic and sedimentary evolution of the Kunlun Pass Basin by Cui Zhijiu et al. （1997, 1998）, is roughly coincident with many important global and Plateau climatic and environmental events, becoming a crucial time interval to understand tectonic-climatic interactions. How-ever, the ages used to constrict the events remain great un-certainty. Here, we present the results of detailed magneto-stratigraphy of the late Cenozoic sediments in the Kunlun Pass Basin, which show the basin sediments were formed between about 3.6 Ma and 0.5 Ma and the Kunlun-Yellow River Movement occurred at 1.2.to0.78 Ma. The lithology, sedimentary facies and lithofacies associations divide the basin into five stages of tectonosedimentary evolution, indi-cating the northern Tibetan Plateau having experienced five episodes of tectonic uplifts at3.6, 2.69-2.58, 1.77, 1.2. 0.87 and0.78 Ma since the Pliocene.

关键词： magnetostratigraphy Kunlun Pass Basin Late Cenozoic Tibetan Plateau.

Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in China

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2.3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (State Key Laboratory of Vegetation and Environmental Change, institute of Botany, Chinese Academy of Sciences, beijing 100093, China) 2.(Graduate University of the Chinese Academy of Sciences, beijing 10004., China) 3 (State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, China) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the Chinese Academy of Sciences Beijing 100049 China) (State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from China, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

VOLUMETRIC CHANGES IN ROCK SUBJECTED TO DIFFERENT STRESS PATHS

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地震工程学报 1985年第4期 87-93页

作者： Geng Naiguang(institute, of Geophysics, State seismological {2., beijing, China)

The volumetric changes in Jinan gabbro and Changping granite subject ed to three different stress paths have been studied. In all cases the rockwas first loaded to a pre-determined stress state below that which would be conducive to fracture. This was then followed by three different cases of loading. Case A: The maximum principal stress was continuously increased to induce fracture. Case B: The minimum principal stress was decreased to induce fracture. Case C. The minimum principal stress was increased to prevent fracture. The experiments showed that for the same rock dilatant behaviour was different along different stress paths. When compared with the dilatant behaviour during case A experiments(i.e. the conventional triaxial experiments) the rocks were found to be in a superdense state for a case B stress path and in an ultra-dilatant state for a case C stress path.

关键词： rock VOLUMETRIC CHANGES IN ROCK SUBJECTED TO DIFFERENT STRESS PATHS ROCK Case

Geophysics and Seismic Hazard Reduction

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Science Foundation in China 2003年第2期 38-42页

作者： Yu Guihua Zhou Yuanze Yu Sheng ( institute of Geology, China seismological {2., beijing 10002. Graduate School, CA S,{4. Department of Earth Sciences, NSFC,{4.)

1 Introduction to the International Research on Geophysics and Seismic Hazard ReductionThe earthquake is a natural phenomenon, which often brings serious hazard to the human life and material possession. It is a physical process of releasing interior energy of the earth, which is caused by interior and outer forces in special tectonic environment in the earth, especially within the lithosphere. The earthquake only causes casualty and loss in the place where people inhabit. Seismic hazard reduction is composed of four parts as seismic prediction, hazard prevention and seismic engineering, seismic response and seismic rescuing, and rebuilding.

关键词： were of Pro de for in

Magnetic Fabric of Cuizhao Pluton and ItsEmplacement Significance

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Journal of Earth Science 1999年第3期18卷 274-279页

作者： Zhou Weixin(institute of Geology, China seismological {2., beijing 10002.)Wan Tianfeng(Department of Geology and Mineral Resources, China University of Geosciences, beijing 100083) institute of Geology China Seismological Bureau Beijing 100029 Department of Geology and Mineral Resources China University of Geosciences Beijing 100083

The new micro-structural and magnetic fabric data on Cuizhao plutou and their emplacement implications are demonstrated in this peper. The magnetic foliations develop better and the degree of magnetic susceptibility anlsotropy is larger in the margin of the pluton than that in the center,which reveals mainly horizontal compression or magma during emplacement- The mapnetic lineations are not very well developed. The magnetic fabrics in the Cuizhao pluton reveal horizontal compression like the bollooning model during emplacement near the Earth surrace. This feature was fixed in later tectonic events.

关键词： granitoid pluton magnetic fabric foliation lineation emplacement mechanism

Fission track age of granite batholith from Southern Tibet:implications for the plateau uplift

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Progress in Natural Science:Materials International 2003年第8期 74-78页

作者： ZHAO Zhidan, MO Xuanxue, GUO Tieying, ZHANG Shuangquan, ZHOU Su, DONG Guochen, WANG Liangliang, ZHANG Fengqin and WAN Jinglin (1. China University of Geosciences, beijing 100083, China 2. institute of Geology, China {2. {4., beijing 10002., China)

Fission track （FT） ages of apatite and zircon from four granite batholiths from Lhasa and Shannan areas are *** FT ages of apatite range from 3.2.8.3 Ma, corresponding to the uplift rates of 0.12.0.2. mm·a-1during this period. The upliftheight is 580m, showing that there is not large-scale rapid uplifting in southern Tibet from 3.2.to 8.3 Ma. The zircon FT ages of Lhasabatholith are 2..9±1.7 and 32.7±2.8 Ma, yielding an uplift rate of 0.08 mm·a-1between 2. and 33 Ma. Combining this work withother studies, it is suggested that the average uplift rate in southern Tibet is low from the time of collision between India and Asian conti-nents to ～3Ma. The uplift of Tibetan Plateau seems to have finished in multi-stage processes with varied rates.

关键词： fission track age uplift rate Lhasa Tibet.

Mineral Coated Fertilizer Effect on Nitrogen-Use Efficiency and Yield of Wheat

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Pedosphere 2005年第4期15卷 526-531页

作者： LI Jian-Yun HUA Quan-Xian TAN Jin-Fang ZHOU Jian-Min HOU Yan-Lin L Department of Soil Environmental Science Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 （China）. State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the Chinese Academy of Sciences Beijing 100039 （China） College of Agriculture Henan Agricultural University Zhengzhou 450002 （China）

A field experiment with winter wheat （Triticum aestivurn L.） was conducted on a silt loam calcaric endorusti-ustic Cambosols derived from the Yellow River alluvial deposits in Henan, China, from 2.01 to 2.02.to evaluate N recovery and agronomic performance of different mineral coated fertilizers （MiCFs） compared to normal urea used in wheat cropping systems under field conditions. Five treatments, including CK （check, no N fertilizer）, urea and three different MiCFs at an equivalent N application rate were established in a randomized complete block design. N release from MiCFs in soil was more synchronous with the N requirement of wheat throughout the growth stages than that from urea, with grain yield of the MiCF treatments significantly higher （P 〈 0.05） than that of the treatment urea. Correspondingly, the N recovery rate was greater for all MiCFs compared to urea, increasing from 32.8% up to 50.1%. Due to its high recovery and low cost, use of the mineral coated N fertilizers was recommended instead of the polymer coated N fertilizers.

关键词： mineral coated fertilizer N recovery urea winter wheat

GENERALIZED REVERBERATION MATRIX FORMULATION FOR WAVE PROPAGATION IN MULTILAYERED MEDIUM

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Acta Mechanica Solida Sinica 2010年第3期23卷 189-199页

作者： Jiayong Tian~★(institute of Crustal Dynamics,China Earthquake Administration,P.O.Box 2.55,beijing {2.,China) institute of Crustal Dynamics China Earthquake Administration Beijing China

Generalized reverberation matrix （GRM） formulation is presented to investigate elastic wave propagation in a complex multilayered solid by the combination of reverberation-ray matrix （RRM） method and stiffness matrix （SM） method. RRM method formulates a reverberation matrix, which reflects the reflection or refraction of the elastic waves in the multilayered solid. However, the dimension of RRM increases as the sublayer number increases, which may result in lower calculation efficiency of the generalized rays. SM formulation yields a system matrix of the constant dimension to promise higher calculation efficiency, but it is difficult to identify the generalized rays. In order to calculate the generalized rays in the complex multi-layered solid efficiently, the RRM formulation is applied to the interested sublayer for the evaluation of the generalized rays and SM formulation to the other sublayers, to construct a generalized reverberation matrix of the constant dimension, which is independent of the sublayer number. Numerical examples show that GRM formulation has higher calculation efficiency for the generalized rays in the complex multilayered-solid configuration compared with RRM formulation.

关键词： elastic waves multilayered medium generalized reverberation matrix stiffness matrix

The Rapid Inversion of 3-D Potential Field and Program Design

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Acta Geologica Sinica(English Edition) 1986年第4期 83-96页

作者： Feng Rui institute of Geophysics, State seismological {2., beijing Yan Huifen and Zhang Ruoshui Geophysical Exploration Party, State seismological {2., beijing

The application of three-dimensional inversion of gravity and magnetic fields is very important not only in geophysical researches, but also in the study of geological structures. A formula of potential field in frequency-domain, developed by Parker in 1973, can be used as a rapid and effective algorithm in gravity and magnetic inversion. The technique has been improved then by Oldenburg, Sprenke, Feng and *** addition to a brief introduction of Parker’s algorithm and its applications, this paper includes the following five parts: basic computational techniques, inversion of single layer, convergence and constraints, simultaneous inversion for density and topography as well as inversion of multilayers. The authors present relevant practical iterative formulas and its varieties when density distribution varies with depth in linear or exponential relation. In order to maintain computation stability and speed up iteration convergence, some approaches are taken in the program design, for instance shifting lower interface of the studied layer, inverting corrections of topography, reducing grid boundary effects and utilizing low-pass filter. With the consideration of the nonuniqueness of the inversion, a method of using seismic data to constrain the range ofpossible models is discussed. It is pointed out that the density variation generates less effects than those of topography on the spectrum of gravity anomaly in second order. Therefore density contrast and topography can be inverted simultaneously by an alternative weighting iteration. By analogy, the inversion of multilayer model can be done in the above procedure. An approach of model decomposition is useful in the computation of multilayer model. The techniques discussed in the present paper for gravitational field are also valid for magnetic field.

关键词： The Rapid Inversion of 3-D Potential Field and Program Design