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通过对繁峙－怀安－太仆寺旗三分向深地震测深宽角反射＼折射剖面的Ｓ波资料进行处理，结合Ｐ波处理结果，给出了地壳上地幔的Ｓ波速度ＶＳ及介质物性参数泊松比σ的二维结构；综合地质及其它地球物理资料，参照国内外岩石物理参数的实验结果，对地壳深部结构、构造及岩性进行了解释和推测。其结论为：中上地壳大部分地区σ值不大于０２５，岩石主要由花岗岩组成，整体呈脆性；其中阳原－怀安间的上地壳下层岩体，含有来自上地幔的无机ＣＯ２气体并还原释放出碳；下地壳及壳幔过渡层σ值大部分大于０２６，整体呈相对塑性；下地壳岩性在怀安以北地区为中酸性麻粒岩、怀安至阳原为英角闪片麻岩、阳原以南为石英岩；莫霍＼过渡层主要由剖面两端的基性麻粒岩－闪岩和剖面中部地区的石英云母片岩－中性麻粒岩所组成。根据σ值的横向变化并结合震相特征，推断了阳原及张北附近的超壳断裂带和怀安的深断裂带。结合地震活动性，对地震较为集中发生的阳原上地壳下层进行了解释，认定是由于该岩体较脆硬且“漂浮”在下部的较塑性岩体之上，受超壳断裂带、区域应力场及上地幔物质上涌的影响，岩体容易在σ值显著变化的部位产生错动、滑动，引发地震，且地震多集中于σ值较小的脆硬岩体一侧。
By processing the S-wave data of the deep seismic reflection depth-broadband reflection / refraction profile in the third part of the Fanzhi-Huai’an-Taibus monastery, the S-wave velocity VS of the crust and upper mantle and the physical property parameters Poisson’s ratio σ. Based on the comprehensive geologic and other geophysical data, the deep crustal structure, tectonics and lithology of the crust are explained and speculated with reference to the experimental results of petrophysical parameters at home and abroad. The conclusion is that the value of σ is not greater than 025 in most parts of middle and upper crust, and the rock is mainly composed of granite, which is brittle as a whole. The upper crustal rock mass between Yangyuan and Huai’an contains inorganic CO2 gas from the upper mantle And the reduction and release of carbon; the σ value of the lower crust and the crust-mantle transitional layer is mostly greater than 026, showing a relative plasticity as a whole; the lithology of the lower crust is acidic granulite in the area north of Huai’an, Hornblende gneiss, quartzite south of Yangyuan; Moho transitional layer is mainly composed of the basic granulite-amphibolite at both ends of the profile and the quartz mica schist-neutral granulite in the middle part of the profile. Based on the lateral variation of σ value and the characteristics of seismic facies, we deduced the supergene crust and the deep fault in Huaian near Yangyuan and Zhangbei. Based on the seismicity, the lower crust in Yangyuan, where earthquakes occur more intensively, is interpreted, which is attributed to the fact that the crust is more brittle and “floating” above the lower plasticiferous rocks, Stress field and upwelling of the upper mantle, the rock mass tends to slip, slippage and cause earthquakes in areas where the σ value changes significantly, and the earthquakes mostly concentrate on the side of the brittle and hard rock body with small σ.