砾石

The host rock conformably overlies a band of siliceous chertybrecia.

含矿主岩整合地硅质燧石角砾石带之。

Charlotte heard the scrunch of boots on gravel.

夏洛特听到了长筒靴走在砾石路嘎吱嘎吱的声响。

He had been so absorbed with watching the building that he hadn't heard footsteps on the gravel path.

他留观察那栋建筑，竟没有听见砾石路的脚步声。