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利用ＣＤＳＮ以及境外的数字地震台网观测的宽频带体波波形资料，采用体波波形反演方法，对中国北部及蒙古地区的上地幔平均Ｐ波速度结构以及部分地区的横向不均匀性特征进行了研究．结果表明，该地区上地幔盖层的Ｐ波速度较低（约７．８～８．０ｋｍ／ｓ），平均盖层厚度约６０ｋｍ，在４１０和６６５ｋｍ附近存在速度跳跃分别为０．２９和０．５５ｋｍ／ｓ左右的速度间断面．准噶尔盆地上地幔顶部Ｐ波速度约７．７ｋｍ／ｓ．上地幔盖层具有较高的速度梯度（平均速度梯度＞０．００５５／ｓ）和较大的厚度（９０～１００ｋｍ），在１４０ｋｍ深处Ｐ波速度可达８．２ｋｍ／ｓ左右．贝加尔湖附近上地幔盖层的平均Ｐ波速度介于８．０～８．０５ｋｍ／ｓ之间，上地幔盖层厚度约３０ｋｍ．
Based on the data of broadband body waveforms observed by CDSN and other overseas digital seismograph networks, the general P wave velocity structure in the upper mantle and the lateral heterogeneity in some areas in northern China and Mongolia were studied by using the body wave waveform inversion method Study. The results show that the P-wave velocities of the upper mantle in the area are low (about 7.8 ~ 8.0km / s) and the average cover thickness is about 60km. The velocity jumps around 410 and 665km are 0.29 and 0 .55km / s about the speed of the cross-section. The P wave velocity at the top of the upper mantle in the Junggar Basin is about 7.7 km / s. Upper mantle facies have high velocity gradient (average velocity gradient> 0.0055 / s) and large thickness (90-100km), and the P wave velocity can reach 8.2km / s at depth of 140km. The average P-wave velocities of upper mantle cover near Lake Baikal are between 8.0 ~ 8.05km / s, and the upper mantle capping thickness is about 30km.