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Science china(Technological Sciences) 2008年第S2期51卷 154-163页

作者： DONG ShaoPeng,HAN ZhuJun & AN YanFen National Center of Seismic Fault Study,Institute of Geology,china Earthquake administration,beijing 100029,china 1. National Center of Seismic Fault Study Institute of Geology China Earthquake Administration Beijing 100029 China

Surface deformation,along National Highway 213.at the epicenter of Wenchuan M8 earthquake,at Yingxiu Town of Sichuan Province,china,is surveyed and measured in *** results show two distinct *** is that no horizontal displacement displays,or dextral strike-slip component at the observation point can not be found basically,the other is that uplift amount is 2.72 m,and the short-ening amount is 0.3. m,which reflects thrust shortening deformation is not *** crust uplift amount of 2.71 m is distributed in a belt with width of 60 *** model of lower crustal flow proposed by Royden et al.(1997) about the dynamic process in eastern margin of the Tibetan Plateau seems more suitable to explain the seismic surface deformation characteristics at Yingxiu Town,the epicenter of the May 12,2008 Wenchuan M8 Earthquake.

关键词： Wenchuan M8 Earthquake Yingxiu Town surface deformation

Characteristics and origin of mafic and ultramafic xenoliths in trachyandesite lavas from Heikongshan volcano,Tengchong,Yunnan Province,china

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Science china Earth Sciences 2010年第9期53卷 1295-1306页

作者： YU HongMei, LIN ChuanYong, SHI LanBin, XU JianDong & CHEN XiaoDe Institute of Geology, china Earthquake administration, beijing 100029, china 1. Institute of Geology China Earthquake Administration Beijing 100029 China

The trachyandesite lavas from Heikongshan volcano of the Tengchong volcanic cluster, Yunnan Province contain relatively abundant mafic and ultramafic small xenoliths comprising mainly gabbro, pyroxenite and rare lherzolites, all less than 2.5 cm in size. Gabbro xenoliths are characterized by "open" texture represented by relatively abundant vesicles and ground-mass fillings, while pyroxenite xenoliths are characterized by equigranular and poikilitic texture. Their mineral compositions (clinopyroxene ± orthopyroxene ± plagioclase) are similar to those of phenocrysts in lavas, and their equilibration temperature (1000-1125°C) is consistent with the crystallization temperature of the phenocrysts (998-1108°C). Thus, the textures and compositions of these xenoliths are different from those of lower crustal and mantle xenoliths, and were derived from the magma chamber. Among them, the gabbroic xenoliths come from the crystal-bubble-liquid zone at the top of the magma reservoir, while the pyroxenite xenoliths come from the cumulates in the bottom of magma reservoir. The studied single lherzolite xenolith with porphyroclastic texture has similar mineral compositions to the mantle xenoliths from eastern china, and is considered to be of upper mantle origin. It was brought into magma reservoir by replenishment magma, and might have experienced a cooling event before eruption. The formation of xenoliths in trachyandesite flows largely reflects the ascent, storage, evolution and eruption processes of magma.

关键词： magma chamber xenoliths geothermo-barometry trachyandesite Heikongshan volcano Tengchong

Reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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Chinese Science Bulletin 2009年第13期54卷 2300-2308页

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2% of the *** reconstructed results indicated a cold span of 153.years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

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Journal of Materials Science & Technology 2001年第2期17卷 215-218页

作者： Cunjian LI and Shaohua LI Welding Research Department, Central Iron & Steel Research Institute, beijing 1.0081. china Yuqing DENG State administration of Metallurgical Industry, beijing 100711, {3. Cent Iron & Steel Res Inst Welding Res Dept Beijing 100081 Peoples R China State Adm Met Ind Beijing 100711 Peoples R China

A formula is derived for determining the influence of temperature and loading rate on dynamic fracture toughness of a high strength low alloy steel (HQ785C) from thermal activation analysis of the experimental results of three-point bend specimens as well as introducing an Arrhenius formula. It is shown that the results obtained by the given formula are in good agreement with the experimental ones in the thermal activation region. The present method is also valuable to describe the relationship between dynamic fracture toughness and temperature and loading rate of other high strength low alloy steels.

关键词： test GB Thermal Activation Analyses of Dynamic FractureToughness of High Strength Low Alloy Steels

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 2855,beijing 100085,china) [a] (Institute of Crustal Dynamics China Earthquake Administration P.O. Box 2855 Beijing 100085 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

Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth Sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2 & CAI YongEn2 1 Institute of Crustal Dynamics, china Earthquake administration, beijing 100085, china 2 Department of Geophysics, Peking University, beijing 100871, china 1. Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China 2. Department of Geophysics Peking University Beijing 100871 China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GPS observation station is most densely deployed in the world. The unprecedented GPS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GPS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2×1020 Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 3..7% caused by the viscous relaxation and 20.7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GPS temporal series data Chi-Chi earthquake

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

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Chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU Fei1,2 & CHAO JiPing3.4 1 Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china 2 Graduate University of Chinese Academy of Sciences, beijing 100049, china 3.National Marine Environmental Forecasting Center, beijing 1.0081. china 4 First Institute of Oceanography, State Oceanic administration of china, Qingdao 266061, china Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China National Marine Environmental Forecasting Center Beijing 100081 China First Institute of Oceanography State Oceanic Administration of China Qingdao 266061 China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件

The upper mantle structure of the Tibetan Plateau and its implication for the continent-continent collision

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Science china Earth Sciences 2005年第8期48卷 1158-1164页

作者： WU Qingju1, ZENG Rongsheng1 & ZHAO Wenjin2 1. Institute of Geophysics, china Earthquake administration, beijing 1.0081. china 2. Institute of Geology, china Academy of Geological Sciences, beijing 10003., china 1. Institute of Geophysics China Earthquake Administration 100081 Beijing China 2. Institute of Geology China Academy of Geological Sciences 100037 Beijing China

The upper mantle structures of Himalayas-Tibet have been obtained from the mi-gration of receiver functions of the teleseismic events recorded by INDEPTH-III. The result of migration imaging shows a dipping interface subducting northward from the depth of 100 km to the 410-km discontinuity underneath southern Tibet. It indicates that the lithospheric mantle of the Indian continent had been detached from the crust and deeply subducted to the upper mantle of Eurasia during the Indo-Eurasian collision. This kind of continent-continent collision process is fundamentally different from the oceanic collision.

关键词： Tibetan Plateau, receiver function, upper mantle structures, Indo-Eurasian collision, dipping interface.

Influences of greenhouse effect on agricultural production in china

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Journal of Environmental Sciences 1990年第4期2卷 3-10页

作者： Gao Suhua, Ding Yihui, Pan Yaru and Zhao Zongci Academy of meteorological Science,State meteorological administration,{3. 1.0081.china

An obvious warming in china induced by doubled carbon, dioxide as simulated by the climatic models have been found. It is also noticed that there might be drying or wetting in some parts of china induced by doubled CO2 as simulated by the general circulation models(GCMs). Agricultural productivity mainly depends on the temperature, rainfall and soil moisture in china. The changes of agricultural productivity in the different parts of china induced by doubled CO2 have been estimated in this paper. It is shown that the greenhouse effect might cause increasing production in some parts of china and decreasing production in other parts of china.

关键词： greenhouse effect agricultural productivity doubled CO2 GCMs climatic productivity force.

Modified vegetation-erosion dynamics model and its application in typical watersheds in the Loess Plateau

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International Journal of Sediment Research 2011年第01期26卷 78-86页

作者： CHEN Yuehong~1,WANG Feixin~2,LIU Guangquan~3.YU Xinxiao~4, JIA Guodong~5,and GAN Ping~6 china Institute of Water Resources and Hydropower Research,beijing 100048 International Research and training Center on Erosion and Sediment Research,beijing 100048,china beijing Forestry University,beijing 100083.china. Key Lab of Dredging Technology of CCGRP,Shanghai Waterway Engineering Design and Consulting Co., Ltd,Shanghai 200120,china. International Research and training Center on Erosion and Sedimentation china Institute of Water Resources and Hydropower Research,beijing 100048 Northwest A&F University,Yangling 712100,china, beijing Forestry University,beijing 100083.china, beijing Forestry University,beijing 100083.china. china Institute of Water Resources and Hydropower Research,beijing 100048,and International Research and training Center on Erosion and Sediment Research,beijing 100048,china [a] Assoc. Prof. Dr. china Institute of Water Resources and Hydropower Research beijing 100048 International Research and training Center on Erosion and Sediment Research beijing 100048 china beijing Forestry University beijing 100083 china [b] Dr. Key Lab of Dredging Technology of CCGRP Shanghai Waterway Engineering Design and Consulting Co. Ltd Shanghai 200120 china [c] Prof. Dr. International Research and training Center on Erosion and Sedimentation china Institute of Water Resources and Hydropower Research beijing 100048 Northwest A&F University Yangling 712100 china [d] Prof. Dr. beijing Forestry University beijing 100083 china [e] Dr. beijing Forestry University beijing 100083 china [f] Engineer china Institute of Water Resources and Hydropower Research beijing 100048 and International Research and training Center on Erosion and Sediment Research beijing 100048 china

The vegetation-erosion model was applied in three typical watersheds of hilly and gully area in the Loess Plateau in northwestern china to study the dynamic relations between vegetation coverage and soil erosion rate and various *** model was improved by introducing rainfall and runoff *** the modified model was applied in the Luergou and Luoyugou *** calculation results with the modified model were compared with the results of the original *** precisions of simulated vegetation coverage and soil erosion rate with the modified model were greatly improved compared with the original *** erosion rate reduced with increasing vegetation coverage and the human disturbance caused high soil erosion.

关键词： Soil erosion Vegetation coverage Vegetation-erosion dynamics model Loess Plateau Modified model