Structures of lithosphere and asthenosphere in Heishi of Sichuan-Hualian of Taiwan profile
AI Xue-lin~1, ZHU Jie-shou~1, CAO Jia-min~1, YUAN Xue-cheng~2 (1.Chengdu University of Technology, China; 2.Development and Research Center, China Geological Survey)
Using the theory and method of modern structural analysis, the paper analyses the artificial (seismic) sounding profiling and tomography of the natural seismic surface wave from Heishui of Sichuan to Hualian of Taiwan, and discovers that high-speed blocks varies in shape and differs in size in the lower lithosphere on the basis of the studies of the geological, geochemical, and geophysical signs. These blocks are termed mantle blocks. This shows that the tectonic pattern of the Heishui of Sichuan-Hualian of (Taiwan) lithosphere and the superficial deformation are basically controlled by the high-speed blocks or the mantle blocks. Based on the systematic studies of the high-speed blocks in the lithosphere, four geometric structural styles (craton-root-shaped, orogen-wedge-shaped, clastic-massive and slaty) are formulated for the first time, and four tectonic evolution types of the lithospheres (cratonic, thickening, thinning, and (oceanic)) are divided. According to the geometric models of the lithosphere from Heishui of Sichuan to Hualian Taiwan, the paper deduces the structural types of asthenosphere, the interaction of lithosphere and asthenosphere, and the continental dynamic types of lithosphere.