| Popis: |
According to the differences of the sediment thickness, basement topography, crustal thickness, water content and volcanic activity of the incoming crust, which are revealed by the newly integrated bathymetric, previous seismic data and the reprocessed seismic line 973, we suggest that the incoming crust along northern Manila Trench can be divided into three areas from north to south: (1) the trapped oceanic crust with thick sediment and relatively thin crust; (2) transitional crust (?) with thin sediment, thick crust and widespread magmatism; and (3) normal SCS crust with relatively thick sediment. This incoming plate variation results in a special style of deformation along the accretionary wedge, including the formation of a weak deformation belt, the reentrant trench geometry and the huge uplift of the upper slope. The middle part may also give rise to profound change in the geometry of the subducted slab and the seismicity of seismogenic structures. |
