Crustal structure and continental dynamics of Central China: A receiver function study and implications for ultrahigh-pressure metamorphism

摘要: Abstract The Qinling–Tongbai–Hong'an–Dabie–Sulu orogenic belt records the tectonic history of Paleozoic convergence between South China and North Blocks. In this study, distribution crustal thickness P - S -wave velocity ratio ( Vp/Vs ) is obtained by using H – k stacking technique from Dabie–Sulu in central China. Our results show marked differences structure Dabie Sulu segments ultrahigh-pressure (UHP) orogen. lower crust dominantly felsic-intermediate composition, whereas beneath segment largely intermediate-mafic. thicker ca. 3–5 km as compared to that surrounding region with presence an ‘orogenic root’. nearly uniform a generally smooth crust–mantle boundary. A symmetrically thickened absence any deep-structural features similar Yangtze block suggests no supportive evidence for proposed northward subduction continental Block. We propose collision Blocks extrusion caused shortening thickening, well delamination crust, resulting asthenospheric upwelling UHP metamorphism along Orogen. also reveal SE NW dipping Moho Block (beneath Tran-North Orogen Eastern Block), suggesting fossil architecture northwestward Kula plate.