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2001年4月~2002年3月,北起河南兰考附近的崔林(34°40′N,114°49′E),南到江西大冶附近的大箕铺(30°20′N,115°03′E),横跨大别造山带,布设了总长度约500km,由34台宽频带流动地震仪组成的二维地震台阵观测剖面.台站采用不等间距布设.在大别造山带范围内,台站间距为3~8km,其他地区为15~20km.利用台阵记录的远震P波波形数据和接收函数方法,获得了横穿大别造山带的接收函数剖面和各台站下方100km深度范围内地壳上地幔的S波速度结构.研究结果表明:大别造山带地壳在垂直山体走向的方向上具有明显的非对称分块结构;地壳最大厚度为42km;壳幔界面具有与地壳分块结构相应的断错结构,最大断距达到8km;在造山带核部,存在壳内横波低速体;壳内低速体分为两部分,分别对应南大别和北大别;在垂向上两者可能曾有差异运动;其下方地壳速度具有随深度增加的梯度结构,上地幔顶部直到70km深度范围内速度异常偏低,而其下方70~100km的深度上有高速异常体.
From April 2001 to March 2002, Cui Lin (34 ° 40’N, 114 ° 49’E) near Lankao, Henan Province went north to Daipi Shop (30 ° 20’N, 115 ° 03’E) across the Dabie orogenic belt, laying a total length of about 500km, composed of 34 broadband mobile seismometers composed of two-dimensional seismic array observation station layout. Station using unequal spacing layout in the Dabie orogen The range of the stations is 3 ~ 8km, and the others are 15 ~ 20km. Using the teleseismic P waveform data recorded by the array and the receiver function method, the cross sections of the receiver function across the Dabie orogenic belt and the stations The S-wave velocity structure of the crust and upper mantle within a depth of 100km below the station shows that the crust of the Dabie orogenic belt has obvious asymmetric block structure in the direction of vertical mountain strike, the maximum crustal thickness is 42km, The fault structure corresponding to the crustal block structure has a maximum fault distance of up to 8km. In the core of the orogenic belt, there exists a low velocity body of shear wave in the shell. The low velocity body in the crust is divided into two parts, corresponding to South Dabie and North Dabie respectively. There may have been differences between the two movements; below the crustal velocity gradient with increasing depth of the structure, the upper mantle top Department until the depth range of 70km anomalies low, while the depth below 70 ~ 100km high-speed anomalous body.