initial oceanic crust的用法和样例：
例句
- The sinking of oceanic crust at subduction zones carries water and carbon dioxide back into the mantle.
在俯冲区洋壳下沉，又把水和二氧化碳带回地下。 - The Ophiolite massifs are composed of mantle peridotite that is mainly harzburgite and dunite, and lacked of crust magmatite within the typical Ophiolite suite.
摘要该蛇绿岩带的岩体由地幔橄榄岩组成，主要岩石类型是方辉橄榄岩和纯橄榄岩，缺少典型蛇绿岩剖面中的洋壳单元。
