西太平洋洋陆板块碰撞

OCEAN-CONTINENT COLLISION IN THE WEST PACIFIC

根据地震震中的空间分布判断,西太平洋板块除了沿日本海沟斜向向黑龙江板块大陆下俯冲外,别的地区大洋板块均近垂直向下回流,未向大陆斜向俯冲。究其原因,可能是这些地区的地幔内所存在的大范围柔性低速岩石圈阻挡了大洋板块的斜向俯冲。中国东部岩石圈的剧变不是太平洋板块俯冲到大陆岩石圈所引起的效应,它的构造动力需要重新认识。

The spatial distribution of epicenters indicates that the mantle of the West Pacific remains in the state of flowing fluid,except for the Japan trench,where the Pacific Plate keeps subducting as a plate,owing to the existence of a soft mantle lithosphere in the region.With the same consideration,it is inferred that the Izanagi plate in the Paleo-Pacific might act in a similar manner and never subducted under the Eurasia.Therefore,the dynamic mechanism of the drastic change of lithosphere in the Eastern Part of China must be reconsidered.