basic lavas

例句：

1. 1. The basic lava flows are the most visible signs of volcanic activity.
   基础岩浆流是火山活动最明显的征兆。
2. 2.The basic lava flows have been studied to understand how they form and evolve over time.
   基础岩浆流的研究有助于我们理解它们是如何形成的以及随着时间的推移如何演变的。
3. 3. The basic lava flows are often used as a reference for geological mapping.
   基础岩浆流常被用作地质制图的参考。