rock mantle

例句：

1. 1.The geologists were studying the rocks in the area to determine their age.
   地质学家正在研究该地区的岩石以确定其年龄。
2. 2. The rock mantle is a key factor in the formation of mountains and valleys.
   岩石盖层是形成山脉和山谷的关键因素。
3. 3. The rock mantle is composed mainly of minerals that are found in the earth's crust.
   岩石盖层主要由地球地壳中发现的矿物组成。