A very common sedimentary rock is called shale, which is a soft rock and was obviously formed by being deposited on the sea bed.
A very common sedimentary rock is called shale, which is a soft rock and was obviously formed by being deposited on the sea bed.
一种十分常见的水成岩叫油页岩，他是一种很软的岩石，很明显是因为被压积在海底而后形成的。