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将远震P波走时残差同区域工业爆破的P波走时相结合,得到了天山地区上地幔的速度结构图象。按照上地幔的性质,此区域可分为两个部分,其分界线位于Talasso-Fergana断层附近。断层东边区域的上地幔结构类似于裂谷带结构,由两个低速层夹一个高速层组成。其上地幔速度与地表起伏有明显的对应关系,这表明天山东部的隆起与上地幔的地热作用有关。而在天山西部,其上地幔具有一稳定地台的结构,而地壳收缩似乎是此地区这一部分的造山作用最可能的解释。岩石层变形方式的不同必然引起天山上述两部分边界上地壳岩石的相对右旋位移,沿Talasso-Fergana断层已观察到了这种概念模式的位移。
Combining the residual travel distance of teleseismic P wave with the P wave travel time of regional industrial blasting, the velocity structure image of the upper mantle in Tianshan area was obtained. According to the nature of the upper mantle, the area can be divided into two parts, with the boundary located near the Talasso-Fergana fault. The upper mantle structure in the eastern margin of the fault resembles a rift zone structure and consists of two high-velocity layers sandwiched between two low-velocity layers. There is a clear correspondence between the velocity of the upper mantle and the surface undulation, indicating that the uplift of the eastern Tianshan Mountains is related to the geothermal effect of the upper mantle. In the western Tianshan, however, the upper mantle has a stable platform structure and crustal contraction seems to be the most likely explanation for orogenicity in this part of the region. The different deformation modes of the rock layers inevitably cause the relative dextral displacement of the crustal rocks above the Tianshan two-part boundary, and the displacement of this conceptual model has been observed along the Talasso-Fergana fault.