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利用中国大陆东部２１个台站的４３条面波大圆路径上瑞利面波记录的双台资料， 计算出双台间地震面波相速度频散，采用Ｔａｒａｎｔｏｌａ概率反演的方法求得相速度频散曲线的分 布，并由各处相速度频散曲线反演得到地壳上地幔的三维横波波速图像，进而得到中国东部 地壳上地幔的Ｓ波速度结构．结果表明：我国大陆东部地壳厚度总体上呈东薄西厚的趋势，以 １０５°Ｅ为界向西地壳厚度逐渐加深到５５ｋｍ以上，其中有一个北东向的ｈ形地壳厚度的坡度 带．豫西及晋南地区为相对薄地壳的地区．大别山地区和泰山附近地区地壳变厚，但秦岭地 区地壳不变厚．上地幔低速层上界面的深度在华北地区较浅，为８０—９０ｋｍ，在鄂尔多斯、四 川东部以及黔湘地区为１２０—１３０ｋｍ．扬子地块东部及华南褶皱系中、东部上地幔顶部速度 偏低使低速层的速度反差不明显．滇黔褶皱系的西部在２００ｋｍ以内的上地幔中未出现低速层。
Using the two sets of data recorded by Rayleigh waves on 43 large circular waves of 21 stations in the eastern part of China, the phase velocity dispersion of the seismic surface in the two stations was calculated. The phase velocity was obtained by Tarantola probability inversion And the distribution of dispersion curves. The three-dimensional shear-wave velocity image of the upper crust and upper mantle is retrieved from the dispersion velocity profiles of all phases, and the S-wave velocity structure of the crust and upper mantle in eastern China is obtained. The results show that the crustal thickness in the eastern part of the continental China tends to be thinner and thinner in the east and west, with the crustal thickness gradually deepening to more than 55km from the west of 105 ° E, including a hilly belt with h-shaped crustal thickness in the northeast. West Henan and South Shanxi are relatively thin crust areas. The crust thickens in the areas around the Dabie Mountains and Taishan, but the crust does not become thick in the Qinling Mountains. The depth of the upper upper mantle low velocity layer in the shallow depth of North China, 80-90km, in Ordos, eastern Sichuan Province and Qianxiang area of 120-130km. The eastern part of the Yangtze block and the South China fold system, the eastern part of the upper mantle velocity is low so that the velocity contrast is not obvious. There is no low velocity layer in the upper mantle below 200km in western Yunnan-Guizhou fold system.