These volcanic event deposits are wide spread in the region and consist mainly of turfs,tuffites and tuffaceous sedimentary rocks.There is some regularity in their temporal-spatial distribution.

• 这些火山事件沉积遍及全区,主要为凝灰岩、沉凝灰岩及凝灰质沉积岩,它们在时空分布上有一定规律。