Seismic anisotropy tomography is the updated geophysical imaging technology that can reveal 3-D variations of both structural heterogeneity and seismic anisotropy, providing unique constraints on geodynamic processes in the Earth’s crust and mantle. Here we introduce recent advances in the theory and application of seismic anisotropy tomography, thanks to abundant and high-quality data sets recorded by dense seismic networks deployed in many regions in the past decades. Applications of the novel techniques led to new discoveries in the 3-D structure and dynamics of subduction zones and continental regions. The most significant findings are constraints on seismic anisotropy in the subducting slabs. Fast-velocity directions (FVDs) of azimuthal anisotropy in the slabs are generally trench-parallel, reflecting fossil lattice-preferred orientation of aligned anisotropic minerals and/or shape-preferred orientation due to transform faults produced at the mid-ocean ridge and intraslab hydrated faults formed at the outer-rise area near the oceanic trench. The slab deformation may play an important role in both mantle flow and intraslab fabric. Trench-parallel anisotropy in the forearc has been widely observed by shear-wave splitting measurements, which may result, at least partly, from the intraslab deformation due to outer-rise yielding of the incoming oceanic plate. In the mantle wedge beneath the volcanic front and back-arc areas, FVDs are trench-normal, reflecting subduction-driven corner flows. Trench-normal FVDs are also revealed in the subslab mantle, which may reflect asthenospheric shear deformation caused by the overlying slab subduction. Toroidal mantle flow is observed in and around a slab edge or slab window. Significant azimuthal and radial anisotropies occur in the big mantle wedge beneath East Asia, reflecting hot and wet upwelling flows as well as horizontal flows associated with deep subduction of the western Pacific plate and its stagnation in the mantle transition zone. The geodynamic processes in the big mantle wedge have caused craton destruction, back-arc spreading, and intraplate seismic and volcanic activities. Ductile flow in the middle-lower crust is clearly revealed as prominent seismic anisotropy beneath the Tibetan Plateau, which affects the generation of large crustal earthquakes and mountain buildings.

地震各向异性层析成像是一种更新的地球物理成像技术，可以揭示结构异质性和地震各向异性的 3-D 变化，为地壳和地幔的地球动力学过程提供独特的约束。在此，我们介绍地震各向异性层析成像理论和应用的最新进展，这得益于过去几十年在许多地区部署的密集地震台网记录的丰富和高质量的数据集。新技术的应用导致了俯冲带和大陆区域的 3-D 结构和动力学方面的新发现。最重要的发现是对俯冲板块中地震各向异性的限制。平板中方位各向异性的快速度方向（FVD）通常与沟槽平行，反映了排列各向异性矿物的化石晶格偏好取向和/或由于在洋中脊产生的转换断层和在海沟附近的外隆起区域形成的板内水化断层而产生的形状偏好取向。板块变形可能在地幔流动和板块内组构中起重要作用。通过剪切波分裂测量广泛观察到前弧中的沟槽平行各向异性，这可能至少部分是由于进入的海洋板块的外上升屈服引起的板内变形。在火山前缘和弧后区域下方的地幔楔中，FVDs 是沟槽正常的，反映了俯冲驱动的角流。沟槽正态 FVD 也显示在亚板块地幔中，这可能反映了上覆板块俯冲引起的软流圈剪切变形。在板块边缘或板块窗口内和周​​围观察到环形地幔流。东亚大地幔楔存在显着的方位和径向各向异性，反映了与西太平洋板块深俯冲及其在地幔过渡带停滞相关的湿热上升流和水平流。大地幔楔中的地球动力学过程导致了克拉通破坏、弧后扩张以及板内地震和火山活动。青藏高原地下中下地壳的韧性流动清晰地揭示出显着的地震各向异性，影响地壳大地震和山地建筑的产生。在板块边缘或板块窗口内和周​​围观察到环形地幔流。东亚大地幔楔存在显着的方位和径向各向异性，反映了与西太平洋板块深俯冲及其在地幔过渡带停滞相关的湿热上升流和水平流。大地幔楔中的地球动力学过程导致了克拉通破坏、弧后扩张以及板内地震和火山活动。青藏高原地下中下地壳的韧性流动清晰地揭示出显着的地震各向异性，影响地壳大地震和山地建筑的产生。在板块边缘或板块窗口内和周​​围观察到环形地幔流。东亚大地幔楔存在显着的方位和径向各向异性，反映了与西太平洋板块深俯冲及其在地幔过渡带停滞相关的湿热上升流和水平流。大地幔楔中的地球动力学过程导致了克拉通破坏、弧后扩张以及板内地震和火山活动。青藏高原地下中下地壳的韧性流动清晰地揭示出显着的地震各向异性，影响地壳大地震和山地建筑的产生。反映了与西太平洋板块深俯冲及其在地幔过渡带停滞相关的湿热上升流以及水平流。大地幔楔中的地球动力学过程导致了克拉通破坏、弧后扩张以及板内地震和火山活动。青藏高原地下中下地壳的韧性流动清晰地揭示出显着的地震各向异性，影响地壳大地震和山地建筑的产生。反映了与西太平洋板块深俯冲及其在地幔过渡带停滞相关的湿热上升流以及水平流。大地幔楔中的地球动力学过程导致了克拉通破坏、弧后扩张以及板内地震和火山活动。青藏高原地下中下地壳的韧性流动清晰地揭示出显着的地震各向异性，影响地壳大地震和山地建筑的产生。