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Finite element modelling for formation of major regions of great earthquakes in the Chinese mainland and its vicinity
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作者 陶玮 洪汉净 刘培洵 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第3期288-294,358,共8页
Great earthquakes of Chinese mainland and its vicinity usually cluster in certain regions during certain periods. We call it major regions of great earthquakes, or major regions briefly in this paper.The major regions... Great earthquakes of Chinese mainland and its vicinity usually cluster in certain regions during certain periods. We call it major regions of great earthquakes, or major regions briefly in this paper.The major regions of different periods can migrate through long distance in space. We have studied mechanism of formation of major regions. It is proposed that the ductile layer of the lithosphere is the place where the major regions form, and deformation of the ductile layer controls the locations and shape of major regions. and the actions of the plate boundaries around the continent are the main driving forces. A two-dimensional viscoelastic finite element model is established to model the deformation field and Stress field of the Chinese mainland and its vicinity The boundary of the model is divided into 12 segments to represent non-uniform of boundary conditions. The stress concentration areas in the continental ductile Iayer are simulated under various compoundings of different boundary scgments. Six models are worked out in which the stress con centration regions are consistent with the realistic major regions. It is proved that stress concentfation regions can be produced in the ductile layer which are roughly in agreement with the realistic major regions under various actions of different boundary segments. 展开更多
关键词 finite element ductile-layer major region boundary segment stress concentration region
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Winter sea ice albedo variations in the Bohai Sea of China 被引量:2
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作者 ZHENG Jiajia KE Changqing SHAO Zhude 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第1期56-63,共8页
Sea ice conditions in the Bohai Sea of China are sensitive to large-scale climatic variations. On the basis of CLARA-A1-SAL data, the albedo variations are examined in space and time in the winter(December, January a... Sea ice conditions in the Bohai Sea of China are sensitive to large-scale climatic variations. On the basis of CLARA-A1-SAL data, the albedo variations are examined in space and time in the winter(December, January and February) from 1992 to 2008 in the Bohai Sea sea ice region. Time series data of the sea ice concentration(SIC), the sea ice extent(SIE) and the sea surface temperature(SST) are used to analyze their relationship with the albedo. The sea ice albedo changed in volatility appears along with time, the trend is not obvious and increases very slightly during the study period at a rate of 0.388% per decade over the Bohai Sea sea ice region.The interannual variation is between 9.93% and 14.50%, and the average albedo is 11.79%. The sea ice albedo in years with heavy sea ice coverage, 1999, 2000 and 2005, is significantly higher than that in other years; in years with light sea ice coverage, 1994, 1998, 2001 and 2006, has low values. For the monthly albedo, the increasing trend(at a rate of 0.988% per decade) in December is distinctly higher than that in January and February. The mean albedo in January(12.90%) is also distinctly higher than that in the other two months. The albedo is significantly positively correlated with the SIC and is significantly negatively correlated with the SST(significance level 90%). 展开更多
关键词 Bohai Sea sea ice region albedo variations in space and time trend sea ice concentration sea ice extent sea surface temperature
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Deep- Seated Tectonic Activation of Tancheng-Lujiang Fault Zone and Its Control over Jiaodong Gold Concentrated Region, China
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作者 Cai Xinping Zhang Baolin Institute of Geology, Chinese Academy of Sciences, Beijing 100029 《Journal of Earth Science》 SCIE CAS CSCD 1999年第1期55-57,共3页
A comprehensive discussion on the deep seated genesis of gold metallogenic materials and the tectono magmatic controls over gold deposits is given in this paper, which is based on the crustal and upper mantle struct... A comprehensive discussion on the deep seated genesis of gold metallogenic materials and the tectono magmatic controls over gold deposits is given in this paper, which is based on the crustal and upper mantle structural characteristics of the Jiaodong massif, the property, activation history and styles of the Tancheng Lujiang fault zone, as well as a series of accompanying tectono magmatic events. Prediction for further prospecting gold deposits in the area is also made. 展开更多
关键词 deep seated tectonic activation Tancheng Lujiang fault zone Jiaodong gold concentrated region.
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Quantitative Prediction of Concentrated Regions of Large and Superlarge Deposits in China
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作者 Wang Shicheng Zhao Zhenyu Wang Yutian Mineral Resources Institute of Comprehensive Information Prediction, Jilin University, Changchun 130026 《Journal of China University of Geosciences》 SCIE CSCD 2003年第3期245-249,共5页
Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nati... Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nationwide in China at a scale of 1∶5 000 000. Using deposit concentrated regions as the model units and concentrated mineralization anomaly regions as prediction units, the prediction is performed on GIS platform. The technical route and research method of locating large and superlarge mineral deposits and principle of compiling attribute table of independent variables and functional variables are proposed. Upon methodology study, the qualitative locating and quantitative predicting mineral deposits are carried out with quantitative theory Ⅲ and characteristic analysis, respectively, and the advantage and disadvantage of two methods are discussed. This research is significant for mineral resource prediction in ten provinces of western China. 展开更多
关键词 mineral deposit prediction quantitative prediction large ore deposits concentrated ore deposit region variable attribute table ore deposits in China
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Interaction due to various sources in saturated porous media with incompressible fluid
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作者 Rajneesh Kumar Ibrahim A.Abbas 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第5期1232-1242,共11页
The disturbance due to mechanical and thermal sources in saturated porous media with incompressible fluid for two-dimensional axi-symmetric problem is investigated.The Laplace and Hankel transforms techniques are used... The disturbance due to mechanical and thermal sources in saturated porous media with incompressible fluid for two-dimensional axi-symmetric problem is investigated.The Laplace and Hankel transforms techniques are used to investigate the problem.The concentrated source and source over circular region have been taken to show the utility of the approach.The transformed components of displacement,stress and pore pressure are obtained.Numerical inversion techniques are used to obtain the resulting quantities in the physical domain and the effect of porosity is shown on the resulting quantities.All the field quantities are found to be sensitive towards the porosity parameters.It is observed that porosity parameters have both increasing and decreasing effect on the numerical values of the physical quantities.Also the values of the physical quantities are affected by the different boundaries.A special case of interest is also deduced. 展开更多
关键词 axi-symmetry incompressible porous medium pore pressure Laplace transform Hankel transform concentrated source and source over circular region
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Spatial analysis and districting of the livestock and poultry breeding in China 被引量:7
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作者 付强 诸云强 +1 位作者 孔云峰 孙九林 《Journal of Geographical Sciences》 SCIE CSCD 2012年第6期1079-1100,共22页
The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world's top first in recent 20 years. Livestock emissions and pollution is... The capacity of livestock breeding in China has increased rapidly since 1949, and the total output of meat, poultry and eggs maintains the world's top first in recent 20 years. Livestock emissions and pollution is closely associated with its population and spatial distribution. This paper aims to investigate the spatial patterns of livestock and poultry breeding in China. Using statistical yearbook and agricultural survey in 2007, the county-level populations of livestock and poultry are estimated as equivalent standardized pig index (ESP), per cultivated land pig index (PCLP) and per capita pig index (PCP). With the help of spatial data analysis (ESDA) tools in Geoda and ArcGIS software, especially the Moran's I and LISA statistics, the nationwide global and local clustering trends of the three indicators are examined respectively. The Moran's I and LISA analysis shows that ESP and PCP are significantly clustering both globally and locally. However, PCLP is clustering locally but not significant globally. Furthermore, the thematic map series (TMS) and related gravity centers curve (GCC) are introduced to explore the spatial patterns of livestock and poultry in China. The indicators are classified into 16 levels, and the GCCs for the three indicators from level 1 to 16 are discussed in detail. For districting purpose, each interval between gravity centers of near levels for all the three indicators is calculated, and the districting types of each indicator are obtained by merging adjacent levels. The districting analysis for the three indicators shows that there exists a potential uniform districting scheme for China's livestock and poultry breeding. As a result, the China's livestock and poultry breeding would be classified into eight types: extremely sparse region, sparse region, relatively sparse region, normally sparse region, normal region, relatively concentrated region, concentrated region and highly concentrated region. It is also found that there exists a clear demarcation line between the concentrated and the sparse regions. The line starts from the county boundary between Xin Barag Left Banner and Xin Barag Right Banner, Inner Mongolia Autonomous Region to the west coast of Dongfang County, Hainan Province. 展开更多
关键词 LIVESTOCK spatial autocorrelation gravity centers curve spatial patterns DEMARCATION the thematicmap series sparse region concentrated region
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