Crustal Structure beneath South China Revealed by Deep Seismic Soundings and Its Dynamics Implications

详细信息   

• 责任者：Deng Yangfan (Guangzhou Institute of Geochemistry ; Chinese Academy of Sciences ; Guangzhou 510640 ; China) ; Li Shoulin
• 刊名：Chinese Journal of Geophysics
• 出版年：2011
• 卷期：54(10)
• 关键词：深地震测深 ; deep seismic sounding ; 地壳结构 ; crustal structure ; 华南地区 ; South China
• 页码：p.2560-2574
• 图表：12 illus., 1 table, 69 refs.
• 分类号：0400
• 出版序号：20122209
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

摘要

///In this paper, the authors collect all DSS profiles in South China, construct the 3D crust velocity model in the region （100°E- 125°E and 18°N-34°N）using robust 3D Kriging interpolation method. The authors discuss the spatial distribution of Moho depth and Pn velocity, analyze the relationship between average velocity and thickness in tectonic units, and investigate the crust character and the subduction direction of Pacific Plate to Eurasian Plate. The results show that 1）the average Moho depth of Yangtze Block is about 40 km, the average crust velocity is 6.30 km/s, while the Moho depth of Cathaysia block is about 32 kin, the average velocity is 6.24 km/s;  2） Sichuan basin has the same character as continental platforms in the world, Cathaysia block has the character of extended continent, Taiwan has the character of continental arcs;  3）the average Pn velocity is 8.02 km/s in Cathaysia block 7.98 km/s in Taiwan orogen, and 7.94 km/s in Yangtze block, including the fastest 8.02 km/s in Sichuan basin and the slowest 7. 75 km/s in east Songpan- Ganzi; and 4) the subduction direction of Pacific plate to Eurasian plate should be NW-SE.