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Structural control of the Gagua “Wedge” Zone east of Taiwan Island on the southern Okinawa Trough

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Science china Earth Sciences 2005年第8期48卷 1165-1174页

作者： ZHENG Yanpeng1,2.3, LIU Baohua2.3, WU Jinlong2. LIANG Ruicai2.3, LIU Chenguang2.3 & ZHANG Zhengmin1 1. Marine Geology College, Ocean University of china, Qingdao 2.6003, china 2. First {2. of Oceanography, State Oceanic administration, Qingdao 2.6061, china 3. Key Laboratory of Marine Sedimentology and Environmental Geology, State Oceanic administration, Qingdao 2.6061, china 1. Marine Geology College Ocean University of China 266003 Qingdao China 2. First institute of Oceanography State Oceanic Administration 266061 Qingdao China 3. Key Laboratory of Marine Sedimentology and Environmental Geology State Oceanic Administration 266061 Qingdao China

Based on compositive analysis and interpretation of the observed and historical data, the geophysical field characters and structural properties of the Gagua “Wedge” Zone of the sea area east of Taiwan Island and the primary tectonic stress direction and its variabilities of backarc spreading in the southern Okinawa Trough are studied. It is concluded from the study results that the Gagua “Wedge” Zone is structurally consistent with the Gagua ridge and two fault basins on both sides of the Gagua ridge, and adjusts the moving direction and distance of the western Philippine Sea plate to make the northwestward motion of the plate on its east side change to the northward subduction of the plate on its west side so that the primary tectonic stress direction of the Okinawa Trough changed from NW-SE to nearly N-S, which provided the stress source for the Okinawa Trough to enter the second spreading stage.

关键词： east of Taiwan Island, Gagua "Wedge" Zone, Okinawa Trough, structural control.

A mathematical model for solid liquid and mass transfer coupling and numerical simulation for hydraulic fracture in rock salt

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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2. and ZHAO Yangsheng1(1. Mining Technology institute, Taiyuan University of Technology, Taiyuan 03002., china 2. Rock and Soil Mechanics institute, Chinese Academy of Sciences, Wuhan 430071, china) Mining Technology institute Taiyuan University of Technology Taiyuan 030024 China. Rock and Soil Mechanics institute Chinese Academy of Sciences Wuhan 43007! China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulations are carried out with the model. The simulation results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulations well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

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 10002., {2. 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 (1000-112.°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

Report on Cardiovascular Health and Diseases in china 2.2.:An Updated Summary

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Biomedical and Environmental Sciences 2024年第9期37卷 949-992页

作者： National Center for Cardiovascular Diseases The Writing Committee of the Report on Cardiovascular Health and Diseases in china Shengshou Hu .

Since 1990,china has made considerable progress in resolving the problem of“treatment difficulty”of cardiovascular diseases(CVD).The prevalent unhealthy lifestyle among Chinese residents has exposed a massive proportion of the population to CVD risk factors,and this situation is further worsened due to the accelerated aging population in *** remains one of the greatest threats to the health of Chinese *** terms of the proportions of disease mortality among urban and rural residents in china,CVD has persistently ranked *** 2.2.,CVD accounted for 48.98%and 47.35%of deaths in rural and urban areas,*** out of every five deaths can be attributed to *** implement a national policy“focusing on the primary health {2. and emphasizing prevention”and truly achieve a shift of CVD prevention and treatment from hospitals to communities,the National Center for Cardiovascular Diseases has organized experts from relevant fields across china to compile the“Report on Cardiovascular Health and Diseases in china”annually since *** 2.2. report is established based on representative,published,and high-quality big-data research results from cross-sectional and cohort population epidemiological surveys,randomized controlled clinical trials,large sample registry studies,and typical community prevention and treatment cases,along with data from some projects undertaken by the National Center for Cardiovascular *** firsthand data not only enrich the content of the current report but also provide a more timely and comprehensive reflection of the status of CVD prevention and treatment in china.

关键词： Cardiovascular disease Risk factor Prevalence Mortality Rehabilitation Basic research Medical device development Health economics

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 100085,{2.) [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

Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3 , LI Congxian\+1 and CONG Youzi\+2.1. Marine Geology Laboratory, Tongji University, Shanghai 2.0092. china 2. First institute of Oceanography, State Oceanic {2. of china, Qingdao 2.6003, china 3. Guangzhou institute of Marine Geology Laboratory Tongji University Shanghai China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China First institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

A review of the New Geophysics:a new understanding of pre-fracturing deformation in the crack-critical crust with implications for hydrocarbon production

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Petroleum Science 2008年第1期5卷 1-12页

作者： Stuart Crampin Yuan Gao School of GeoSciences University of Edinburgh UK Edinburgh Anisotropy Project British Geological Survey Edinburgh UK institute of earthquake Science China Earthquake Administration Beijing China

This paper reviews a new understanding of shear-wave splitting （seismic-birefringence） that is a fundamental revision of conventional fluid-rock deformation. It is a New Geophysics with implications for almost all solid-earth geosciences, including hydrocarbon exploration and production, and earthquake forecasting. Widespread observations of shear-wave splitting show that deformation in in situ rocks is controlled by stress-aligned fluid-saturated grain-boundary cracks and preferentially orientated pores and pore-throats pervasive in almost all igneous, metamorphic, and sedimentary rocks in the Earth＇s crust. These fluid-saturated microcracks are the most compliant elements of the rock-mass and control rock deformation. The degree of splitting shows that the microcracks in almost all rocks are so closely spaced that they verge on fracture-criticality and failure by fracturing, and are critical systems with the “butterfly wing＇s” sensitivity of all critical systems. As a result of this crack-criticality, evolution of fluid-saturated stress-aligned microcracked rock under changing conditions can be modelled with anisotropic poroelasticity （APE）. Consequently, low-level deformation can be： monitored with shear-wave splitting; future behaviour calculated with APE; future behaviour predicted with APE, if the change in conditions can be quantified; and in principle, future behaviour controlled by feed-back. This paper reviews our current understanding of the New Geophysics of low-level pre-fracturing deformation.

关键词： Crack anisotropy New Geophysics pre-fracturing deformation seismic birefringence,shear-wave splitting

Size fractionated biomass and productivity of phytoplankton and new production in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999

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Acta Oceanologica Sinica 2003年第4期22卷 651-670页

作者： Cai Yuming 1,3, Ning Xiuren 1,2.3, Zhu Genghai3, Shi Junxian3 1. Key Laborary of Submarine Geosciences of State Oceanic administration,Hangzhou 310012.china. 2. Key Laborary of Ocean Dynamic Processes and Satellite Oceanography of State Oceanic administration,Hangzhou 310012.china 3. Second institute of Oceanography of State Oceanic administration, Hangzhou 310012.china Key Lab Submarine Geosci State Ocean Adm Hangzhou 310012 Peoples R China Key Lab Ocean Dynam Proc Satellite Oceanog State Ocean Adm Hangzhou 310012 Peoples R China Inst Oceanog State Ocean Adm 2 Hangzhou 310012 Peoples R China

The paper deals with the studies on the cell abundance, the composition of dominant species, size fractionated biomass and productivity of phytoplankton, new production, the environmentally restricted mechanism in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999. The results showed that there was marked feature of spatial zonation in the sea areas investigated. In the Prydz Bay and its adjacent continental shelf, the biomass and productivity of phytoplankton were high; those of continental slope and open ocean area were obviously low. The nutrient concentration had opposite distribution trend, due to the consumption of phytoplankton. It mainly affected by the vertical stability of water column, grazing pressure of zooplankton, temperature and light etc. The results of size-fractionation showed that the average contribution of netplankton to total chlorophyll a in studied sea areas was 52.2.%, those of nano- and picoplankton were 2..4 % and 18.4 %, respectively. The average contribution of netplankton to total primary production was 52.4 %, those of nano- and picoplankton were 2..7 % and 18.9 %, separately. It is same as previous conclusion that the contribution of picoplankton to productivity is slightly larger than that to biomass of phytoplankton communities. The average new production and f-ratio were 2.0.6 mg/ (m(2.)d) and 0.43, respectively.

关键词： phytoplankton standing stock primary productivity size-fractionation new production the Southern Ocean

Revision of seismic design codes corresponding to building damagesin the “5.12. Wenchuan earthquake

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earthquake Engineering and Engineering Vibration 2010年第2期9卷 147-155页

作者： Wang Yayong institute of earthquake Engineering, {2. Academy of Building Research, Beijing 100013, {2. institute of earthquake Engineering China Academy of Building Research Beijing 100013 China

A large number of buildings were seriously damaged or collapsed in the "5.12. Wenchuan earthquake. Based on field surveys and studies of damage to different types of buildings, seismic design codes have been updated. This paper briefly summarizes some of the major revisions that have been incorporated into the "Standard for classification of seismic protection of building constructions GB502.3-2.08" and "Code for Seismic Design of Buildings GB50011-2.01." The definition of seismic fortification class for buildings has been revisited, and as a result, the seismic classifications for schools, hospitals and other buildings that hold large populations such as evacuation shelters and information centers have been upgraded in the GB502.3-2.08 Code. The main aspects of the revised GB50011-2.01 code include: (a) modification of the seismic intensity specified for the Provinces of Sichuan, Shanxi and Gansu; (b) basic conceptual design for retaining walls and building foundations in mountainous areas; (c) regularity of building configuration; (d) integration of masonry structures and precast RC floors; (e) requirements for calculating and detailing stair shafts; and (f) limiting the use of single-bay RC frame structures. Some significant examples of damage in the epicenter areas are provided as a reference in the discussion on the consequences of collapse, the importance of duplicate structural systems, and the integration of RC and masonry structures.

关键词： Wenchuan earthquake earthquake damage to buildings revision of seismic design codes