A group of A-Kr dating data of volcanic rocks in Taiwan Island is listed in thes paper, which clarifies the data of volcanic activity. And according to changes of plate movement in East Asia, a basic regularity of the...A group of A-Kr dating data of volcanic rocks in Taiwan Island is listed in thes paper, which clarifies the data of volcanic activity. And according to changes of plate movement in East Asia, a basic regularity of the volcanic activity in Taiwan can be obtainted, i.e. it is closely related with plate movement. The volcanic activity in Taiwan has always been moving about since Mesozoic, as the island lies in a special place of plate tectonic in East Asia, and the volcanic activity zone has changed with variations of plate motion. The paleo-Pacific plate launched a subduction toward the west in Cretaceous. Kula plate took a subduction toward the north from Cretaceous to Eogene. In Oligocene, the direction of the subduction of the Pacific plate changed from northward to westward. Taiwan Island has been the first to be affected by this change since Miocene Epoch. Therefore, volcanic activity occurs in the middle and the east of Taiwan Island. In addition, as the border of subduction moved eastward, the volcanic activity zone moves toward the east, too.Penglai movement in the period ranging from Tertiary to Quatemary is the most magnificent transformation in geological history of Taiwan. As the subduction movement of the Philippine Sea plate was replaced by the collision with Taiwan crust, the volcanic activity in the east of Taiwan Island ceased. Only the northem island and some offshore islands constitute a part of the Quatemary volcanic arc where the signs of volcanic activiy has been still displayed by now. However, the volcanic activity of the Penghu Island Group fell into the same category as that in Quatemary which was caused by the fracture activations in the eastem coast of China.展开更多
文摘A group of A-Kr dating data of volcanic rocks in Taiwan Island is listed in thes paper, which clarifies the data of volcanic activity. And according to changes of plate movement in East Asia, a basic regularity of the volcanic activity in Taiwan can be obtainted, i.e. it is closely related with plate movement. The volcanic activity in Taiwan has always been moving about since Mesozoic, as the island lies in a special place of plate tectonic in East Asia, and the volcanic activity zone has changed with variations of plate motion. The paleo-Pacific plate launched a subduction toward the west in Cretaceous. Kula plate took a subduction toward the north from Cretaceous to Eogene. In Oligocene, the direction of the subduction of the Pacific plate changed from northward to westward. Taiwan Island has been the first to be affected by this change since Miocene Epoch. Therefore, volcanic activity occurs in the middle and the east of Taiwan Island. In addition, as the border of subduction moved eastward, the volcanic activity zone moves toward the east, too.Penglai movement in the period ranging from Tertiary to Quatemary is the most magnificent transformation in geological history of Taiwan. As the subduction movement of the Philippine Sea plate was replaced by the collision with Taiwan crust, the volcanic activity in the east of Taiwan Island ceased. Only the northem island and some offshore islands constitute a part of the Quatemary volcanic arc where the signs of volcanic activiy has been still displayed by now. However, the volcanic activity of the Penghu Island Group fell into the same category as that in Quatemary which was caused by the fracture activations in the eastem coast of China.
