The mining company's report explained how mineral deposits form deep within the Earth's crust.

這家礦業公司的報告說明了礦藏如何在地殼深處形成。

Our tour guide said the island was created when the ocean crust cracked open.

我們的導遊說，這座島是在海洋地殼裂開時形成的。

The engineering team must study the crust beneath the site before approving the new factory.

工程團隊在核准新工廠之前，必須先研究廠址下方的地殼。