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利用诸城-宜川人工地震折射/宽角反射剖面的资料,得到了华北克拉通南部岩石圈二维速度结构.结果表明,太行山东西两侧岩石圈结构存在着巨大的差异.东侧较薄,为70～80km;西侧较厚,为85～120km.在太行山重力梯度带附近,岩石圈厚度出现了约30km的突变.岩石圈地幔和下地壳介质的P波速度值东侧较低,西侧较高.东侧的中下地壳内存在不同尺度的低速体,西侧则尚未发现.这些差异表明,太行山重力梯度带也是一条岩石圈厚度突变带和岩石成分分隔带.根据Pm波的波形特点,推测东部地区的莫霍面不再是一个尖锐的间断面,而是一个复杂的过渡带.初步分析认为,上地幔物质的热机械-化学侵蚀作用是引起太行山东侧岩石圈减薄和破坏的主要机制,太平洋板块俯冲是改变华北克拉通岩石圈地幔性质的重要动力学因素.
Using the data of Zhucheng-Yichuan artificial refraction / wide-angle reflection profile, the two-dimensional velocity structure of the lithosphere in the southern part of North China Craton has been obtained.The results show that there is a huge difference in lithospheric structure between the two sides of the Taihang Mountains, Is 70-80 km, and the thickness of the west side is 85-120 km. Near the gravity gradient zone of the Taihang Mountains, a sudden change of about 30 km in lithosphere thickness occurs. The values of P-wave velocities in lithospheric mantle and lower crust are lower on the east side and west The upper and lower crust in the east is characterized by low velocity bodies with different scales and the west side has not yet been found.These differences show that the Taihangshan gravity gradient zone is also a lithospheric thickness mutation zone and rock component separation zone.According to the waveform of Pm wave It is presumed that the Moho in the eastern part of China is no longer a sharp discontinuity but a complicated transitional zone.A preliminary analysis shows that the thermomechanical and chemical erosion of the upper mantle material is caused by the thinning of the lithosphere in the east part of the Taihang Mountains and The main mechanism of vandalism and subduction of the Pacific plate are the important dynamic factors that change the lithospheric mantle in the North China Craton.