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研究了中、新生界沉积层所覆盖的我国西北各沉积盆地：准噶尔盆地、塔里木盆地、柴达木盆地，以及一系列中小型盆地和其邻近地域的深部岩石层三维速度结构，探讨其和造山带与油气田的关系．使用了适配滤波频时分析方法，分析了我国数字台网的中长周期瑞利面波资料，计算得到２５７条混合路径的面波群速度频散．利用改进的分格随机反演理论与方法，从混合路径中提取了１００条频散突出路径的４°×４°网格单元的纯路径频散，并反演研究区的三维Ｓ波速度结构．频散的周期从１．９５ｓ到１５１．７ｓ，浅部分辨率可达１ｋｍ，得出了该区深达２００ｋｍ范围内三维瑞利波群速度的分布与特征．所得结果表明：塔里木盆地、哈密－吐鲁番盆地、伊宁盆地以及藏北地区的羌塘盆地具有较好的油气前景．我国西北邻国接壤地带，也均为良好的油气盆地潜在地带．
The three-dimensional velocity structures of the deep lithostratigraphic layers in northwestern China, which are covered by the sediments of Meso-Cenozoic, in the Junggar Basin, Tarim Basin, Qaidam Basin, and a series of small and medium-sized basins and their adjacent areas are studied, Relationship between belt and oil and gas fields. Using the method of adaptive filtering time-frequency analysis, the long-period periodic Rayleigh wave data of digital network in China was analyzed and the surface wave group velocity dispersion of 257 hybrid paths was calculated. By using the improved stochastic backstepping theory and method, the pure path dispersions of 4 ° × 4 ° grid elements of 100 scattered paths are extracted from the hybrid path and the 3D S-wave velocity structure is retrieved . The period of the dispersion is from 1.95s to 151.7s and the resolution of the shallow part is up to 1km. The distributions and characteristics of the three-dimensional Rayleigh wave velocities within the range of 200km are obtained. The results show that the Tarim Basin, the Hami-Turpan Basin, the Yining Basin and the Qiangtang Basin in northern Tibet have a good prospect of oil and gas. The contiguous zone bordering the northwest of our country is also a potential oil and gas basin potential.