basaltic achondrite best initial

例句：

1. 1.The basalt is a type of volcanic rock that is very hard and dense.
   玄武岩是一种非常硬和密实的火山岩石。
2. 2. The basalt formation is an important geological feature in the region.
   玄武岩形成是该地区的一个重要地质特征。
3. 3.The basalt layer was formed by the cooling of magma beneath the Earth's surface.
   玄武岩层是由地球表面以下熔岩冷却形成的。