Characteristics of azimuthal anisotropy in SE Tibetan plateau and its relationship with the background of block structure

The southeastern Tibetan Plateau, which includes the Yangtze Block, and Cathaysia is geotectonically situated in compound part of Tethys-Himalayan tectonic domain Peninsular Pacific domain. It one critical regions for studying scientific problems plateau material lateral escape, lithosphere deformation, geotectonic properties blocks, deep dynamics. In this study, we use ambient noise data recorded by 401 broadband stations to obtain high-resolution short-period (T = 4–32 s) Rayleigh wave azimuthally anisotropic phase velocity maps. These could provide fresh clues an in-depth understanding crust-mantle structure, deformation mechanism, evolution Plateau. Within Simao block, strikes faults orientations principal compressive stress field both generally coincide with fast-wave polarization direction (FPD). FPD near Lancangjiang fault zone west NE-SW direction, Wuliangshan center NS Red River east NW-SE direction. We estimate that southwest Plateau has a controlling effect on crustal likewise blocked Lincang granite belt, resulting strong deformation. crust middle significantly different from strike. Combining seismic activity GPS results, depth 8 km below surface completely locked, conclude anisotropy upper related action regional field. Taking into account geochemical thermochemical speculate complex at junction blocks leads prominent characteristics FPDs azimuthal crust, suggesting Shizong-Mile may be western boundary between block block.