岩层 (yán céng) — rock stratum, rock formation

Definition

Examples

• 这些岩层形成于亿万年前。
  Zhè xiē yán céng xíng chéng yú yì wàn nián qián.
  These rock strata formed billions of years ago.
• 研究岩层可以知道地球的变化。
  Yán jiū yán céng kě yǐ zhī dào dì qiú de biàn huà.
  Studying rock strata can tell us about changes to the Earth.
• 这座山由多层岩层组成。
  Zhè zuò shān yóu duō céng yán céng zǔ chéng.
  This mountain is composed of multiple layers of rock strata.