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Can Industrial Structure Upgrading Restrain Industrial Land Expansion?Evidence from China
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作者 CHEN Wei LI Qiao +1 位作者 ZHANG Sun ZHOU Xue 《Chinese Geographical Science》 SCIE CSCD 2024年第3期504-518,共15页
China has made great achievements in industrial development and is transforming into a powerful manufacturing country.Meanwhile,the industrial land scale is also expanding.However,whether industrial structure upgradin... China has made great achievements in industrial development and is transforming into a powerful manufacturing country.Meanwhile,the industrial land scale is also expanding.However,whether industrial structure upgrading achieves the purpose of restraining industrial land expansion remains unanswered.By calculating the industrial land structure index(ILSI)and industrial land expansion scale(ILES),this study analyzed their temporal and spatial distribution characteristics at both regional and city levels from 2007to 2020 in China.Results show that industrial land expansion presents a different trend in the four regions,the ILES in the eastern region is the largest,and the speed of industrial land expansion has declined since 2013,but it has gradually increased since 2016.The ILSI of the eastern and central regions is higher than that of the western and northeastern regions.Furthermore,a spatial Durbin model(SDM)has been established to estimate the spatial effect of industrial structure upgrading on industrial land expansion from 2007 to2020.Notably,industrial structure upgrading has not slowed industrial land expansion.The eastern and western regions require a greater amount of industrial land while upgrading the industrial structure.The improvement of the infrastructure level and international trade level has promoted industrial land expansion. 展开更多
关键词 industrial development industrial structure upgrading industrial land expansion regional differences China
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Study upon the Spatial Structure of Regional Eco-tourism-Based upon the Perspective of Supply and Demand and Competition Field
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作者 方世敏 赵金金 《Journal of Landscape Research》 2010年第10期51-55,共5页
Along with the coming of the low-carbon era, people have paid more and more attention to the natural environment and eco-tourism will embrace a huge development. From the perspectives of the market relationship of sup... Along with the coming of the low-carbon era, people have paid more and more attention to the natural environment and eco-tourism will embrace a huge development. From the perspectives of the market relationship of supply-demand in economics and of field competition in physics, this paper has discussed upon the present status of the spatial structure of eco-tourism, and analyzed the relationship between supply-demand and field, in order to clarify the direction for the balance between supply and demand in the field and to guide eco-tourism to the way of sustainable development. 展开更多
关键词 regional ECO-TOURISM Spatial structure Supply-demand COMPETITIVE FIELD
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Geological structure of the yellow sea area from regional gravity and magnetic interpretation 被引量:37
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作者 Zhang Minghua Xu Deshu Chen Jianwen 《Applied Geophysics》 SCIE CSCD 2007年第2期75-83,共9页
Regional gravity and aeromagnetic data covering the area of 32°- 38° N, 118°-127° E at the scale of 1:1,000,000 are coordinated and integrated in a synthetic study of the South China Yellow Sea an... Regional gravity and aeromagnetic data covering the area of 32°- 38° N, 118°-127° E at the scale of 1:1,000,000 are coordinated and integrated in a synthetic study of the South China Yellow Sea and adjacent areas. Depth to magnetic crystalline basement and its structure are determined by magnetic anomaly inversion. Depth to and thickness of the Paleozoic rock are also revealed by gravity anomaly inversion with constrains of the basement and known seismic information from several profiles. Structure units, main faults, basin boundaries, and sub-suppressions are outlined on the basis of gravity data interpretation. 展开更多
关键词 Yellow Sea gravity and magnetic interpretation regional structure oil basins.
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Empirical Study on Effect of Industrial Structure Change on Regional Economic Growth of Beijing-Tianjin-Hebei Metropolitan Region 被引量:7
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作者 CHEN Hongxia LI Guoping 《Chinese Geographical Science》 SCIE CSCD 2011年第6期708-714,共7页
Based on the data of gross domestic product(GDP),industrial added value and the proportion of industrial employees from 2000 to 2008,this paper studies the effect of industrial structure change on the regional economi... Based on the data of gross domestic product(GDP),industrial added value and the proportion of industrial employees from 2000 to 2008,this paper studies the effect of industrial structure change on the regional economic growth of Beijing-Tianjin-Hebei Metropolitan Region in China using the shift-share method.The results show that:1) In the 21st century,the industrial output of three industries,namely,primary,secondary,and tertiary,and the GDP grew rapidly in the study period.The tertiary industry grew the fastest;it had the largest contribution to the GDP and mean-while had become the most competitive industry in the metropolitan region.2) The development of cities within the region was not balanced.Firstly,compared with Tianjin,Beijing,as one of the two core cities,was more rational in the industrial structure.Secondly,the surrounding eight cities,which are Shijiazhuang,Qinhuangdao,Tangshan,Langfang,Baoding,Cangzhou,Zhangjiakou,and Chengde,were all uncompetitive than the two core cities.3) There was a great industrial gradient in the region(especially between the two core cities and the cities of Tangshan,Baoding,Zhangjia-kou,Chengde,Cangzhou,and Langfang).As a result,it is foreseeable that the industry transfer in the Bei-jing-Tianjin-Hebei Metropolitan Region will be one of the trends in regional development,and the industry transfer is inevitably to promote the regional integration. 展开更多
关键词 Beijing-Tianjin-Hebei Metropolitan region economic growth shift-share analysis industrial structure
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Models of Spatial Structures of Regional Multi-element Geochemical Anomalies over Copper-Polymetallic Orefields 被引量:5
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作者 SHI Changyi and ZHANG Jinhua China University of Geosciences, Beijing 100083 Institute of Geophysical and Geochemical Exploration, Langfang Hebei 065000 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2003年第1期72-80,共9页
Regional stream sediment surveys at a 1:200,000 scale reveal positive andnegative regional multi-element geochemical anomalies over medium to large copper-polymetallicorefields of different genetic types in China. Reg... Regional stream sediment surveys at a 1:200,000 scale reveal positive andnegative regional multi-element geochemical anomalies over medium to large copper-polymetallicorefields of different genetic types in China. Regional geochemical anomalies of orefield refer tothose geochemical anomalies that are related to metallogenesis of an orefield in a certain area. Theanomaly area is typically 10 to 100 km^2. The regional multi-element anomalies related tomineralization can be divided into three groups, that is, the ore-element anomaly association,indicator element anomaly association, and metallogenic environmental element anomaly association.Their common spatial distributions over ore deposits or orefields possess unique structures. Themodel of spatial structure of regional multi-element geochemical anomalies (RAGSS) of an orefielddelineates structural feature possessed by orderly spatial distributions of different groups ofmulti-element anomaly associations related to orefield metallogenesis. It is used to outline thecommon metallogenetic anomaly visage that is composed of the orderly spatial distribution ofdifferent groups of multi-element anomaly associations. The orderly spatial distribution ofmulti-element anomalies over an orefield reflects element distributions as they are changed from adispersed 'out-of-order' state into a concentrated 'orderly' state during the mineralization of anorefield. Three different patterns of the spatial anomaly structure related to mineralization in anorefield can be concluded: (1) nested pattern; (2) eccentric pattern and; (3) peripheral pattern.There are marked differences between multi-element anomaly patterns related and not related tomineralization. RAGSS models of orefields can be used to better understand and evaluate regionalmulti-element anomalies and identify ore types. 展开更多
关键词 orefield regional geochemical anomaly model anomaly structure RAGSSmodel
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Joint Inversion of the 3D P Wave Velocity Structure of the Crust and Upper Mantle under the Southeastern Margin of the Tibetan Plateau Using Regional Earthquake and Teleseismic Data 被引量:12
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作者 LI Dahu LIAO Hua +4 位作者 DING Zhifeng ZHAN Yan WU Pingping XU Xiaoming ZHENG Chen 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第1期16-33,共18页
The special seismic tectonic environment and frequent seismicity in the southeastern margin of the Qinghai-Tibet Plateau show that this area is an ideal location to study the present tectonic movement and background o... The special seismic tectonic environment and frequent seismicity in the southeastern margin of the Qinghai-Tibet Plateau show that this area is an ideal location to study the present tectonic movement and background of strong earthquakes in China's Mainland and to predict future strong earthquake risk zones. Studies of the structural environment and physical characteristics of the deep structure in this area are helpful to explore deep dynamic effects and deformation field characteristics, to strengthen our understanding of the roles of anisotropy and tectonic deformation and to study the deep tectonic background of the seismic origin of the block's interior. In this paper, the three-dimensional (3D) P-wave velocity structure of the crust and upper mantle under the southeastern margin of the Qinghai-Tibet Plateau is obtained via observational data from 224 permanent seismic stations in the regional digital seismic network of Yunnan and Sichuan Provinces and from 356 mobile China seismic arrays in the southern section of the north-south seismic belt using a joint inversion method of the regional earthquake and teleseismic data. The results indicate that the spatial distribution of the P-wave velocity anomalies in the shallow upper crust is closely related to the surface geological structure, terrain and lithology. Baoxing and Kangding, with their basic volcanic rocks and volcanic clastic rocks, present obvious high-velocity anomalies. The Chengdu Basin shows low-velocity anomalies associated with the Quaternary sediments. The Xichang Mesozoic Basin and the Butuo Basin are characterised by low- velocity anomalies related to very thick sedimentary layers. The upper and middle crust beneath the Chuan-Dian and Songpan-Ganzi Blocks has apparent lateral heterogeneities, including low-velocity zones of different sizes. There is a large range of low-velocity layers in the Songpan-Ganzi Block and the sub-block northwest of Sichuan Province, showing that the middle and lower crust is relatively weak. The Sichuan Basin, which is located in the western margin of the Yangtze platform, shows high-velocity characteristics. The results also reveal that there are continuous low-velocity layer distributions in the middle and lower crust of the Daliangshan Block and that the distribution direction of the low-velocity anomaly is nearly SN, which is consistent with the trend of the Daliangshan fault. The existence of the low-velocity layer in the crust also provides a deep source for the deep dynamic deformation and seismic activity of the Daliangshan Block and its boundary faults. The results of the 3D P-wave velocity structure show that an anomalous distribution of high-density, strong-magnetic and high-wave velocity exists inside the crust in the Panxi region. This is likely related to late Paleozoic mantle plume activity that led to a large number of mafic and ultra-mafic intrusions into the crust. In the crustal doming process, the massive intrusion of mantle-derived material enhanced the mechanical strength of the crustal medium. The P-wave velocity structure also revealed that the upper mantle contains a low-velocity layer at a depth of 80-120 km in the Panxi region. The existence of deep faults in the Panxi region, which provide conditions for transporting mantle thermal material into the crust, is the deep tectonic background for the area's strong earthquake activity. 展开更多
关键词 3D P-wave velocity structure China seismic array detection Panxi region Chuan-DianBlock Daliangshan Block southeastern margin of Qinghai-Tibet Plateau
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URBAN REGIONAL STRUCTURES TRANSFORMATION AND SUSTAINABLE DEVELOPMENT: CASE STUDY OF NANJING MEGALOPOLIS 被引量:1
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作者 XU Yi-lun WU Qi-yan REN Dong-ming 《Chinese Geographical Science》 SCIE CSCD 2000年第4期32-38,共7页
s: Since 1978, many changes have happened on the background of urban regional structure in China, such as the economy system restructuring, the social transforming including the population flow accelerating and social... s: Since 1978, many changes have happened on the background of urban regional structure in China, such as the economy system restructuring, the social transforming including the population flow accelerating and social demand diversifying and individualizing, the political and economic systems reforms, the rise of the real estate market and the changing relationship between human and nature. From the macroscopic view, these changes make the national urban system to be a newer pattern with a widening gap among the cities in spite of the rising of the cities as a whole. At the same, the urban land use structures are changing with both the trends of intensification and diversification, and the trends of the regional diversification and the economic integration. Besides, urban structures with multiple centers are emerging in several metropolitan areas in China. These changes and trends mentioned above are confirmed by a case study of Nanjing City, a growing metropolitan area in east China. The case study also points out some problems in urban regional structure reforming, especially the poor social and ecological considerations. We should pay more attention to some ideas like balance of intensification and decentralization, development of suburban centers and a reasonable mixing of the functional activities to develop a sustainable urban regional structure. 展开更多
关键词 urban regional structure Nanjing megalopolis sustainable development
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Analysis on The In? uence of Regional Financial Development to The Upgrading of Regional Industrial Structure 被引量:1
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作者 Sun Yingmin 《International Journal of Technology Management》 2017年第2期70-72,共3页
This paper mainly introduces the regional , nance in detail,points out that the goal of industrial structure is more reasonable and advanced,expounds the influence of regional financial development on the upgrading of... This paper mainly introduces the regional , nance in detail,points out that the goal of industrial structure is more reasonable and advanced,expounds the influence of regional financial development on the upgrading of regional industrial structure,puts forward some suggestions for regional financial development to further promote the upgrading of the structure. 展开更多
关键词 region FINANCE industrial structure UPGRADE in fiuence
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NUMERICAL CLASSIFICATION OF REGIONAL STRUCTURE OF AGRO-ECOSYSTEM IN GUANGDONG
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作者 罗曼嘉 《Chinese Geographical Science》 SCIE CSCD 1991年第2期60-71,共12页
On the basis of 'The Statistical Data of Guangdong Province in 1981' and the 14 selected original variables, 107 counties and suburbs in Guangdong are classified. In the classification, cluster analysis is app... On the basis of 'The Statistical Data of Guangdong Province in 1981' and the 14 selected original variables, 107 counties and suburbs in Guangdong are classified. In the classification, cluster analysis is applied, and the cluster hierarchy of the agro-ecosystem is achieved with a computer. According to output level, planting structure, and input level of energy, there is an evident regionalism in the agro-ecosystem of Guangdong, which presents approximately concentric circles centralized by Guangzhou City. 展开更多
关键词 AGRO-ECOSYSTEM regional structure CLUSTER analysis LOCATION QUOTIENT
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REGIONAL STRUCTURE OF CAPITAL MARKET OF FOREIGN DIRECT INVESTMENT IN CHINA’S MAINLAND
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作者 焦华富 《Chinese Geographical Science》 SCIE CSCD 1999年第2期11-16,共6页
Since China's reform and open door, the countries and regions of direct investment in China's mainland have been increasing. In 1995, the amount of foreign direct investment (FDI) in China was US$ 37.81 bill... Since China's reform and open door, the countries and regions of direct investment in China's mainland have been increasing. In 1995, the amount of foreign direct investment (FDI) in China was US$ 37.81 billion that was from more than 170 countries and regions. The regional structure of capital market of FDI in China has three characteristics: (1) The most of FDI was from the near countries or regions, Hong Kong Macao, Taiwan, Japan, South Korea, Thailand and Malaysia provided 80.3% of the amount of FDI in 1995. (2) Only several countries and regions provided most of FDI in China. (3) According to the contributory rate, the main capital market of FDI in China could be divided into four classes, including the guiding market, subsidiary market, new and development market, opportunity market. Most of FDI in China was from the developing countries and regions, which had a negative effect on the size and technical level of foreign capital enterprises. The author puts forward the countermeasures to improve the regional structure of capital market: (1) to keep the guiding market stable, (2) to open up chiefly the subsidiary market, (3) to guide actively the new and developing market, (4) to try hard to start the opportunity market. 展开更多
关键词 FOREIGN DIRECT INVESTMENT (FDI) CAPITAL MARKET regional structure
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Mechanism of realizing industrial structure upgrading through technology-driven regional innovation capacity
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作者 KONG Shu-guang CHEN Yu-chuan 《Chinese Business Review》 2008年第9期46-52,61,共8页
Based on the analysis of the formation process of regional innovation capacity, this paper expatiates that the technology is the basis for industrial structure upgrading, while technological innovation is the power of... Based on the analysis of the formation process of regional innovation capacity, this paper expatiates that the technology is the basis for industrial structure upgrading, while technological innovation is the power of regional innovation capacity. It points out that the essential of regional industrial structure upgrading is the transition of regional technology structure from one balance to another. The mechanism of realizing industrial structure upgrading through technology-driven regional innovation capacity is also discussed briefly. 展开更多
关键词 TECHNOLOGY regional innovation capacity industrial structure upgrading MECHANISM
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The Enlightenment of Regional Spatial Structure Theory to Rural Revitalization Strategy
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作者 Jingjing ZHANG Ni DAN Yan GAO 《Agricultural Biotechnology》 CAS 2022年第6期139-144,154,共7页
The rural revitalization strategy is a macro-strategic guide to solve the problem of"weak links"in the coordinated development of rural and urban regions.Geography responded positively to the national strate... The rural revitalization strategy is a macro-strategic guide to solve the problem of"weak links"in the coordinated development of rural and urban regions.Geography responded positively to the national strategy and made a preliminary discussion on the scientific theoretical basis and research direction of rural revitalization strategy.The paper integrated application of the spatial structure theory of geography and the time-space research scientific thinking,respectively discussed the core edge theory,growth pole and point axis theory,theory of stage of industrialization and urbanization,rural settlement type,infrastructure construction patterns,such as the theoretical guidance and application of strategy of rejuvenating rural to rural revitalization of the full implementation of the strategy to provide theoretical support and practical guidance. 展开更多
关键词 Rural revitalization strategy regional economic Spatial structure theory
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Classification of regional agricultural structure:method and its application to China
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作者 Mou Ziping Lei Hongmei +1 位作者 Chen Guangping Li Xin 《Ecological Economy》 2008年第4期410-417,共8页
Regional agriculture is the basis of regional sustainable development, so sustainable regional agricultural development is essential to the sustainable development of the whole society and becomes the focus of global ... Regional agriculture is the basis of regional sustainable development, so sustainable regional agricultural development is essential to the sustainable development of the whole society and becomes the focus of global research. The classification of regional agricultural structure is the basic work of regional agriculture study. This paper constructs index system (27 indices) of regional agricultural structure types with the three big indices: natural resources, developmental level of the agro-economy, and agro-ecological conditions. This paper also endows weight to every sub-classification index by means of AHP and obtains the comprehensive evaluation value of the three types of indices with arithmetic average weight approach. The regional agricultural structure can be classified into eight types in accordance with this evaluation results. The empirical study of China shows that the 31 provinces (municipalities and autonomous regions) are of different agriculture structural types. Finally, countermeasures of sustainsable agricultural development are put forward for the different agriculture structure features. 展开更多
关键词 AGRO-ECOLOGY China Classification method regional agriculture structural type
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An Empirical Research of Producer Services' Cluster Development To Regional Industrial Structure Optimization And Upgrading --Based on the Research of 16 central cities' Panel Data in Yangtze River Delta
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作者 LI Zhen-bo ZHANG ming-dou 《International Journal of Technology Management》 2015年第10期80-87,共8页
Based on the 16 central cities' Panel Data in Yangtze River Delta, location quotient index is used in this paper to measure and analyze the current cluster situation of producer services in Yangtze River Delta, fixed... Based on the 16 central cities' Panel Data in Yangtze River Delta, location quotient index is used in this paper to measure and analyze the current cluster situation of producer services in Yangtze River Delta, fixed effects model of Panel Data model is also used in this paper, and the industrial structure is taken as the dependent variable, while the core explanatory variables is the degree of producer services' cluster development, which is calculated by location quotient, moreover, three control variables introduced in this paper and they are technology advantage, education level and R&D spending, and the mentioned above is to empirically study the impacts of producer services' cluster development to the regional industrial structure. As a result, producer services' cluster development has a significant positive role in promoting the regional industrial structure optimization and upgrading, though the extent is not yet a big push and is still to be further strengthened. In this paper, it has provided a strong evidence that under China' s new normal economy, producer services is badly needed to promote regional industrial structure, and finally it makes specific suggestions based on the current cluster situation of producer services in Yangtze River Delta. 展开更多
关键词 producer services location quotient regional industrial structure optimization and upgrading
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A Study on Investment Structure of Fixed Assets and Regional Economic Growth
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作者 Zhenzhen Liu 《Proceedings of Business and Economic Studies》 2020年第3期73-76,共4页
Nowadays,it has been in the period of rapidly developing China’s economy.Since the financial crisis in 2008,China has paid more and more attention to investing in fixed assets,and the growth rate of investing in fixe... Nowadays,it has been in the period of rapidly developing China’s economy.Since the financial crisis in 2008,China has paid more and more attention to investing in fixed assets,and the growth rate of investing in fixed asset is also rising.However,when promoting regional economic growth,if we only pay attention to the total amount of fixed asset investment,there will inevitably exist some blindness and lack of sustainability.Therefore,the study between the investment structure of fixed assets and regional economic growth is quite important.China has a vast territory and many regions.The investment structure of fixed assets in different regions is also different,so the influence on economic growth is also different.This paper analyzes the investment structure of fixed assets and regional economic growth,and help realize the rapid growth of regional economy by recognizing the current situation of China's investment structure of fixed assets. 展开更多
关键词 Investment structure of fixed assets region Economic growth
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Three dimensional shear wave velocity structure of crust and upper mantle in South China Sea and its adjacent regions by surface waveform inversion 被引量:22
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作者 曹小林 朱介寿 +2 位作者 赵连锋 曹家敏 洪学海 《地震学报》 CSCD 北大核心 2001年第2期113-124,共12页
We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). I... We assembled approximately 328 seismic records. The data set was from 4 digitally recording long-period and broadband stations of CDSN. We carried out the inversion based on the partitioned waveform inversion (PWI). It partitions the large-scale optimization problem into a number of independent small-scale problems. We adopted surface waveform inversion with an equal block (2((2() discretization in order to acquire the images of shear velocity structure at different depths (from surface to 430 km) in the crust and upper-mantle. The resolution of all these anomalies has been established with (check-board( resolution tests. These results show significant difference in velocity, lithosphere and asthenosphere structure between South China Sea and its adjacent regions. 展开更多
关键词 面波波形 分块波形反演 三维S波速度结构 中国数字地震台网 “检验板”法 岩石圈
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Structural plane recognition from three-dimensional laser scanning points using an improved region-growing algorithm based on the robust randomized Hough transform 被引量:1
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作者 XU Zhi-hua GUO Ge +3 位作者 SUN Qian-cheng WANG Quan ZHANG Guo-dong YE Run-qing 《Journal of Mountain Science》 SCIE CSCD 2023年第11期3376-3391,共16页
The staggered distribution of joints and fissures in space constitutes the weak part of any rock mass.The identification of rock mass structural planes and the extraction of characteristic parameters are the basis of ... The staggered distribution of joints and fissures in space constitutes the weak part of any rock mass.The identification of rock mass structural planes and the extraction of characteristic parameters are the basis of rock-mass integrity evaluation,which is very important for analysis of slope stability.The laser scanning technique can be used to acquire the coordinate information pertaining to each point of the structural plane,but large amount of point cloud data,uneven density distribution,and noise point interference make the identification efficiency and accuracy of different types of structural planes limited by point cloud data analysis technology.A new point cloud identification and segmentation algorithm for rock mass structural surfaces is proposed.Based on the distribution states of the original point cloud in different neighborhoods in space,the point clouds are characterized by multi-dimensional eigenvalues and calculated by the robust randomized Hough transform(RRHT).The normal vector difference and the final eigenvalue are proposed for characteristic distinction,and the identification of rock mass structural surfaces is completed through regional growth,which strengthens the difference expression of point clouds.In addition,nearest Voxel downsampling is also introduced in the RRHT calculation,which further reduces the number of sources of neighborhood noises,thereby improving the accuracy and stability of the calculation.The advantages of the method have been verified by laboratory models.The results showed that the proposed method can better achieve the segmentation and statistics of structural planes with interfaces and sharp boundaries.The method works well in the identification of joints,fissures,and other structural planes on Mangshezhai slope in the Three Gorges Reservoir area,China.It can provide a stable and effective technique for the identification and segmentation of rock mass structural planes,which is beneficial in engineering practice. 展开更多
关键词 3D laser scanning Rock discontinuity structural plane Intelligent recognition Robust randomized Hough transform Improved region growing algorithm
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Crust and Upper Mantle Electrical Resistivity Structure in the Panxi Region of the Eastern Tibetan Plateau and Its Significance 被引量:10
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作者 ZHANG Gang WANG Xuben +7 位作者 FANG Hui GUO Ziming ZHANG Zhaobin LUO Wei CAI Xuelin LI Jun LI Zhong WU Xing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期531-541,共11页
The Panxi region is located in the frontal zone of positive squeezing subduction and side squeezing shearing between the Indian plate and the Eurasian plate. The long-period magnetotelluric (LMT) and broadband magne... The Panxi region is located in the frontal zone of positive squeezing subduction and side squeezing shearing between the Indian plate and the Eurasian plate. The long-period magnetotelluric (LMT) and broadband magnetotelluric (MT) techniques are both used to study the deep electrical conductivity structure in this region; magnetic and gravity surveys are also performed along the profile. According to the 2-D resistivity model along the Yanyuan-Yongshan profile, a high- conductivity layer (HCL) exists widely in the crust, and a high-resistivity block (HRB) exists widely in the upper mantle in general, as seen by the fact that a large HCL exists from the western Jinpingshan tectonic zone to the eastern Mabian tectonic zone in the crust, while the HRB found in the Panxi tectonic zone is of abnormally high resistivity in that background compared to both sides of Panxi tectonic zone. In addition, the gravity and magnetic field anomalies are of high value. Combined with geological data, the results indicate that there probably exists basic or ultrabasic rock with a large thickness in the lithosphere in the Panxi axial region, which indicates that fracture activity once occurred in the lithosphere. As a result, we can infer that the high-resistivity zone in the Panxi lithosphere is the eruption channel for Permian Emeishan basalt and the accumulation channel for basic and ultrabasic rock. The seismic sources along the profile are counted according to seismic record data. The results indicate that the most violent earthquake sources are located at the binding site of the HRB and the HCL, where the tectonic activity zone is generally acknowledged to be; however, the earthquakes occurring in the HCL are not so violent, which reflects the fact that the HCL is a plastic layer, and the fracture threshold of a plastic layer is low generally, making high stress difficult to accumulate but easy to release in the layer. As a result, a higher number of smaller earthquakes occurred in the HCL at Daliangshan tectonic zone, and violent earthquakes occurred at the binding site of high- and low-resistivity blocks at the Panxi tectonic zone. 展开更多
关键词 EARTHQUAKE deep electrical resistivity structure long-peroid magnetotelluric Emeishanbasalt Panxi region
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Molar-Tooth Structure from the Mesoproterozoic Wumishan Formation in Lingyuan,Yanshan Region,North China,and Geological Implications 被引量:6
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作者 KUANG Hongwei LIU Yongqing +4 位作者 PENG Nan LUO Shunshe LI Jiahua CEN Chao CHEN Mingpei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第1期85-95,共11页
Although its origin has not yet reached a consensus so far, MTS (Molar-Tooth Structure) has been documented for more than 100 years. Current study reports a discovery of MTS from the Mesoproterozoic Wumishan Formati... Although its origin has not yet reached a consensus so far, MTS (Molar-Tooth Structure) has been documented for more than 100 years. Current study reports a discovery of MTS from the Mesoproterozoic Wumishan Formation, Lingyuan, Yanshan Region, North China, and the features and geological implications of MTS are further discussed. Here, straitigraphic horizons of MTS's occurrences show that it was mainly located within the top part of the Wumishan Formation, i.e., limestone unit. Four kinds of morphology of MTS, i.e., fine fusiform, debris, ribbon, ptigmatic and nodular (irregular), were recognized and thought to be highly related to the sedimentary environments and facies. Geochemistry of MTS including oxides, trace elements and C, O and Sr isotopes indicates that the horizons of MTS-bearing is of higher Sr/Ba and Ca/Mg ratios, lower positive ~13C and highly negative 3180 values than the adjacent stratigraphic levels of rare MTS. Lithology, morphology and geochemistry of MTS in the Wumishan Formation suggest that MTS occurs mainly in shallow subtidal near the storm wave base, which is typically characterized by warm temperature, oversaturated calcium carbonate seawater and high organic productivity. Furthermore, occasional enrichment of algae bacteria here is more favorable for the calcification of calcium oozes and catalytic for MTS. C isotope composition of the Wumishan Formation and MTS of this study is well correlated with that of the Mesoproterozoic Belt Supergroup, North America and Riphean, Siberia, suggesting that MTS acts as a sedimentary record responding to global changes and is a perfect indicator in Precambrian stratigraphic correlation worldwide. 展开更多
关键词 Molar-tooth structure Wumishan Formation MESOPROTEROZOIC IMPLICATIONS Lingyuan Yanshan region
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A study on 3-D velocity structure of crust and upper mantle in Sichuan -Yunnan region, China 被引量:6
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作者 王椿镛 Mooney W.D +3 位作者 王溪莉 吴建平 楼海 王飞 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第1期1-17,共17页
Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is deter... Based on the first arrival P and S data of 4 625 regional earthquakes recorded at 174 stations dispersed in the Yunnan and Sichuan Provinces, the 3-D velocity structure of crust and upper mantle in the region is determined, incorporating with previous deep geophysical data. In the upper crust, a positive anomaly velocity zone exists in the Sichuan basin, whereas a negative anomaly velocity zone exists in the western Sichuan plateau. The boundary between the positive and negative anomaly zones is the Longmenshan fault zone. The images of lower crust and upper mantle in the Longmenshan fault, Xianshuihe fault, Honghe fault and others show the characteristic of tectonic boundary, indicating that the faults likely penetrate the Moho discontinuity. The negative velocity anomalies at the depth of 50 km in the Tengchong volcanic area and the Panxi tectonic zone appear to be associated with the temperature and composition variations in the upper mantle. The overall features of the crustal and the upper mantle structures in the SichuanYunnan region are the lower average velocity in both crust and uppermost mantle, the large crustal thickness variations, and the existence of high conductivity layer in the crust or/and upper mantle, and higher geothermal value. All these features are closely related to the collision between the India and the Asia plates. The crustal velocity in the SichuanYunnan rhombic block generally shows normal value or positive anomaly, while the negative anomaly exists in the area along the large strike-slip faults as the block boundary. It is conducive to the crustal block side-pressing out along the faults. In the major seismic zones, the seismicity is relative to the negative anomaly velocity. Most strong earthquakes occurred in the upper-mid crust with positive anomaly or normal velocity, where the negative anomaly zone generally exists below. 展开更多
关键词 regional earthquake Moho discontinuity 3-D velocity structure network method plate collision SEISMICITY
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