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用天然地方震以及近震Ｐ、Ｓ波到时资料反演了甘肃７个分区的地壳结构。其速度非均匀分布表明：就垂向非均匀性而言，河西大于河东，海原、古浪两个８级大震区大于周围地区，横向非均匀性正好相反，但无论垂向还是横向非均匀性都是上地壳（大约以１９ｋｍ深度为界）大于中下地壳；青藏块体东北缘速度自ＳＳＷ向ＮＮＥ的东北角规则变化，上中地壳（约以３０ｋｍ深度为界）内沿该方向递减，下地壳及上地幔顶部递增；横向非均匀性以低速区带为主，大致沿祁连山断裂系向ＳＳＥ直到兰州附近，再沿近ＮＳ向到舟曲武都，中间与近ＥＷ向直到康乐和政的西秦岭北缘断裂低速带交接，高速区主要在嘉峪关、玉门以北，景泰附近及兰州以南等处；中强以上地震不仅在低速区带发生，而且也在高速区及其它地方发生，两个８级大震震源区速度在研究区中地壳内为最低，要注意兰州附近及张掖民乐地区可能潜在的强震危险区。
Using natural local earthquakes and near-epicenter P and S wave arrival data, the crustal structure of 7 subregions in Gansu was inverted. The nonuniform distribution of velocity shows that in the case of vertical inhomogeneity, the Hexi area is larger than that of the surrounding area in the two large 8th magnitude earthquakes such as Hedong, Haiyuan and Gulang, and the horizontal heterogeneity is just the opposite. However, both the vertical and horizontal non-uniformities Is higher than that of the middle and lower crust in the upper crust (about 19km depth); the northeastern margin of the Qinghai-Tibet block changes regularly at the northeast corner from SSW to NNE and decreases along the direction of the upper middle crust (about 30km depth) , The lower crust and the top of the upper mantle increase gradually. The horizontal heterogeneity is dominated by low-velocity zones, which are generally along the Qilian fault system toward SSE until near Lanzhou and then along the near NS to Zhouquwudu, the middle and near EW until Kanglehe At the junction of Jiayuguan, north of Yumen, Jingtai and south of Lanzhou, the high-speed zone is not only in the low-speed zone, but also in the high-speed zone and other places Occurred, the velocity of the source area of the two M8-magnitude earthquakes was the lowest in the middle crust in the study area, and attention should be paid to the potential strong earthquakes in the vicinity of Lanzhou and the Minle area in Zhangye Danger zone.