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2001年5～11月,在大别造山带西段的新县、红安地区(31°20~31°50′N,114°30′~115°E)架设了宽频带数字地震流动台阵.采用接收函数方法对台阵记录的高质量远震P波数据进行反演,获得了大别造山带西段的S波速度剖面和地壳上地幔精细结构.研究结果显示,研究区的地壳厚度整体上较薄,约为32~38km,莫霍面自南向北倾斜.在台阵北缘对应桐城-桐柏剪切带处,莫霍面发生错断,断距达到4~6km,显示桐城-桐柏剪切带为早中生代扬子板块与华北板块碰撞的古缝合带的南界.在上地幔顶部存在向北倾斜东西向延伸的S波低速带,显示出大别山造山带与毗邻华北块体之间的拼合关系.在台阵南部下地壳底部存在高速体,这可能和拆沉作用以后,发生大规模拉张作用相伴随的幔源基性岩浆在下地壳下部的底侵作用有关.
From May to November in 2001, a broadband digital seismic mobile array was set up in Xin’an and Hongan areas (31 ° 20 ~ 31 ° 50’N, 114 ° 30 ’~ 115 ° E) in the western section of the Dabie orogenic belt The receiver function method was used to invert the high-quality teleseismic P-wave data recorded by the array to obtain the S-wave velocity profile and the fine structure of the crust and upper mantle in the western segment of the Dabie orogenic belt.The results show that the crustal thickness As a whole, it is thin, about 32 ~ 38km, and the Moho slopes from south to north.When the northern part of the array corresponds to the Tongcheng-Tongbai shear zone, the Moho has a fault with a break of 4 ~ 6km, which shows that The Tongcheng-Tongbai shear zone is the southern boundary of the ancient suture colliding with the Early Mesozoic Yangtze Plate and the North China Plate. There is an S-wave low-velocity belt extending eastwards and northwards to the north at the top of the upper mantle, indicating that the Dabie orogen and the adjacent North China block The high-velocity bodies exist at the bottom of the lower crust in the south of the platform, which may be related to the under-invasion of mantle-derived basic magma underlying the lower crust following the delamination.