利用地震台阵观测资料研究大庆地区深部构造

利用绥芬河-满洲里地学断面上布设的流动地震台阵，并结合固定地震台记录到的2009年6月-2011年5月间的远震资料，通过有限频方法开展体波走时层析成像研究，获取研究区上地幔三维P波速度结构；采用瑞利面波双台相速度和背景噪声相速度层析成像方法，反演研究区的三维S波速度结构。应用两种方法最终得到大庆地区三维速度分布特征。结果显示：松辽盆地地壳厚度较薄，盆地周边的大、小兴安岭隆起区厚度变厚，松辽盆地地壳内部多存在低速异常，壳幔及上地幔与周边相比呈现高速异常，分析上地幔物质上升会造成局部高速异常结构。速度结构异常多是南北向或北北东向，可能与区域性断裂对上、中地壳影响有关。

Deep Structure Based on Seismic Array Observations in Daqing Area

We combine the data from the mobile seismic array in Suifenhe-Manzhouli geoscience transect with those from the permanen tstations recorded from June, 2009 to May, 2011, the information are used for calculating the three-dimensional P-wave velocity structure of upper mantle in the study area according to body wave travel-time tomography, which is based on the limited frequency method.The proposed to mography method includes double-station phase velocity of Rayleigh wave and phase velocity of background noise, the three-dimensional S-wave velocity structure in the study area can be calculated by using the inversion. Finally, the two methods obtain the three-dimensional velocity distribution in Daqing area. The results show that the crust of Songliao basin is thin and the crusts of Da Hinggan Mountains and Xiao Hinggan Mountains around the Songliao basin are thick. The crust often has low velocity anomaly in the Songliao basin, the crust-mantle boundary and upper mantle show high velocity anomaly compared with the neighboring regions. The reason of local high-speed anomalies may be due to the rise of mantle material. Velocity anomalies usually show NS or NNE, which may be related to the impact of regional faults on the upper and middle crust.