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对包含大别－苏鲁碰撞造山带在内的东经 １１２°－１２４°，北纬２８°－３９°区域进行地 震层析成像研究，重建其地壳及上部地幔的三维速度图像．结果表明：造山带岩石圈速度横 向不均匀性显著；大别造山带以商城－麻城断裂为界，东侧的大别地块与西侧红安地块在地 壳速度上是两个不同的速度块体；中地壳 １５—２５ｋｍ深度范围内存在低速带，与伸展滑脱构造 有关；南、北大别构造单元之下，莫霍面下凹，地壳内发育了速度为６．５－６．６ｋｍ／ｓ、向北倾斜的 相对高速体，与超高压变质岩体相对应；在大别－苏鲁造山带下方的上部地幔中存在向北倾 斜的板片状高速体，结合已有地质、地球化学证据推测，它是三叠纪俯冲的扬子地块的残留 体；俯冲板片在深部发生了断离．本文利用地震层析成像方法揭示的造山带岩石圈速度结构 细节，对研究与地表地质有关的地球动力学无疑是十分重要的．
Seismic tomography imaging of 112 ° -124 ° E and 28 ° -39 ° N latitude, including the Dabie-Sulu collision orogenic belt, is carried out to reconstruct the 3D velocity images of the crust and the upper mantle. The results show that the lithospheric velocity of the orogenic belt is highly heterogeneous in horizontal direction. The Dabie orogenic belt is bounded by the Shangcheng-Macheng fault and the Dabie block on the east and the Hongan block on the west are two different velocities Block. There is a low-speed zone in the depth range of 15-25 km in the middle crust, which is related to the extension and detachment structure. Under the units of South and North Dabies, the Moho is indented and the velocity in the crust is 6.5-6.6 km / s, and the relatively high-velocity body inclined northward corresponds to the UHP metamorphic rock mass. In the upper mantle below the Dabie-Sulu orogenic belt, there is a plate-shaped high-velocity body inclined to the north. Combining the existing geology and geochemistry Evidence suggests that it is a remnant of the Triassic subducted Yangtze block; the subducting slab was severed in the deep. In this paper, the details of lithospheric velocity structure of orogenic belt revealed by seismic tomography are undoubtedly very important for studying the geodynamics related to surface geology.