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利用中国东北地区CCDSN台网4个台站和PASSCAL 19个台站的802条远震接收函数,以三维地壳上地幔速度模型为背景,用共转换点相位加权叠加(CCP-PWS)偏移技术,对研究区(120°～132°E,38°～48°N)上地幔间断面进行了成像.结果表明:在深度620km附近存在一个明显的低速层,而且在更靠近研究区西太平洋俯冲带东部较浅,深度约600km.经与前人研究结果对比,认为该低速层很可能是由西太平洋俯冲板块中的洋壳从俯冲板块分离并滞留堆积而形成.另外,受西太平洋俯冲板块的影响,660km间断面深度在研究区明显增大,最深达到700km,而且在其东北角明显呈现为多级间断面.
Based on the 3D crust-upper-mantle velocity model, 802 remote-seismic receiver functions of 4 stations at CCDSN station and 19 stations at PASSCAL in northeastern China were used, and the co-conversion point phase weighted stacking (CCP-PWS) , The mantle discontinuity was imaged in the study area (120 ° -132 ° E, 38 ° -48 ° N) .The results show that there is a clear low-velocity layer near the depth of 620 km and closer to the western part of the study area With a shallow east and a depth of about 600 km.Compared with previous studies, it is concluded that the low-velocity layer is probably formed by the separation and accumulation of the oceanic crust in the western Pacific subduction plate from the subducted plate.In addition, The depth of the 660km section increases obviously in the study area, reaching the deepest 700km, and obviously presents as a multistage inter-section in the northeast corner.