第三纪下层

例句：

1. 1. The geological formations of the third epoch are crucial for understanding Earth's history.
   第三纪的地质构造对于理解地球历史至关重要。
2. 2. The study of the lower strata in the third epoch sheds light on the development of life on Earth.
   研究第三纪下层地层有助于揭示地球上生命的发展。
3. 3. The discovery of ancient fossils in the lower strata of the third epoch has provided newinsights into the evolution of life.
   在第三纪下层地层的发现为古生物演化提供了新的见解。