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针对我国东南边缘及其邻近区域地幔对流应力场分布形态与地表构造活动特征的相关性问题,提出利用Runcorn模型及高阶卫星重力球谐系数计算欧亚板块与菲律宾板块复合接触带及其邻近区域的地幔对流应力场。结果显示,地幔对流应力矢量特征与地震应力场分布具有较好的一致性。在两大板块的接触部位均出现了显著的应力增强与汇聚趋势,同时在琉球海沟的弧后扩张带上出现的较强的地幔对流应力发散带。而在各板块相对稳定的内部区域存在微弱的地幔发散流。通过计算和分析得出,该区域下地壳小尺度的地幔对流可能是控制这一区域型构造过程的重要因素之一。
Aiming at the correlation between the distribution of convective stress field and the characteristics of surface tectonic activity in the southeastern margin of China and its adjacent areas, the Runcorn model and the harmonic coefficients of high-order satellite gravitational sphere are proposed to calculate the complex contact zone between the Eurasian plate and Philippine plate and its adjacent regions Of the mantle convection stress field. The results show that the mantle convection stress vector and seismic stress field distribution have good consistency. In the contact area between the two plates, significant stress intensification and convergence tendency appeared, and strong convective stress divergence zone appeared on the arc back extension belt of the Ryukyu Trench. In the relatively stable interior of each plate there is a weak divergence of the mantle. Through calculation and analysis, it is concluded that the small-scale mantle convection in the lower crust of the region may be one of the important factors controlling the regional tectonic process.