华南陆块在中生代经历了强烈的岩浆活动，花岗岩分布广泛。虽然处于西太平洋俯冲带上方，但华南陆块在新生代时期没有明显的构造运动，地震活动性较弱。在华南陆块的东南缘的地表热流较高的观测值与大量出露的花岗岩吻合，但与由地震波速度扰动推测的冷壳、热幔和较薄的岩石圈结构相矛盾。华南陆缘是否存在上地壳热、中下地壳冷和上地幔较热的分层温度结构，需要直接的观测资料来约束。作为探测深部结构、物质构成和物理状态的重要参数，地震波衰减比速度对深部物质温度和热动力学过程更为敏感。本项申请拟采用上地壳震相Pg、全地壳震相Lg、在上地幔顶部传播的Pn和Sn波等，构建华南陆块岩石圈的宽频带高分辨的地震波衰减分层模型，建立上地壳、中下地壳和上地幔顶部的精细三维热结构，厘清生热、传导和运移等热动力学过程，为华南陆块岩石圈构造演化研究提供新的地震学证据。

Strong magmatic activities occurred in Mesozoic in the South China continental block, where granites were widely distributed. Although situated above the western Pacific subduction zone, the South China block was stable during the Cenozoic, where no obvious tectonic movement was observed and the seismicity was weak. The higher surface heat flux observed in the southeastern margin of the South China block coincides with a large number of outcropped granites, but is inconsistent with the cold crust, hot mantle and thinner lithospheric structures inferred from seismic velocity perturbations. To answer the question whether there are stratified temperature structures in the continental margin of South China, such as hot in the upper crust, clod in the middle and lower crust and hotter in the uppermost mantle, the directly observed data are required. As an important parameter for detecting deep structure, material composition and physical state, seismic attenuation is more sensitive to temperature and thermodynamic process compared to seismic velocity. In this study, we will construct a broadband high-resolution seismic attenuation stratification model for the lithosphere in the South China continental block by using the upper crust Pg and entire crust Lg phases and the Pn and Sn waves propagating within the uppermost mantle, and then establish a fine three-dimensional thermal structure with the upper crust, middle and lower crust and uppermost mantle to clarify the thermodynamic processes of heat generation, conduction and migration, so as to provides new seismological evidence for investigating tectonic evolution for the lithosphere in the South China continental block.