How is gravel and sand mined?

A floating dredge digs gravel and sand from the bottom, pours them into the truck body through a conveyor. Sometimes gravel is mined from the bottom of rivers to deepen them and prevent spring floods.

Raw materials for industry

Sand is the smallest rock particles. At a chemical plant, it is ground into other substances. For example, glass is blown out of sand containing quartz. Of the other types of sand, the cement is needed for any construction site. Most of the gravel taken from the bottom of the rivers falls on our roads to make them harder. A heavy skating rink rolls and presses gravel. Then they put a layer of asphalt on top - and the highway is ready.

Interesting fact:Gravel and sand are not always mined from the bottom of rivers. In quarries, special machines beat large stones and grind them into coarse or fine sand.

Clay

In some places where there are no stones in the soil, the water of rivers and streams does not seep deep into the earth, but precipitates in a layer of fine dust and softens it. This forms clay - a plastic material that easily takes any shape. They make bricks, dishes and other objects from clay.

Landslide

Under the soil layer are thick layers of clay. If they are located on the hillsides, they become dangerous: after heavy rains, the clay softens, and everything that stands on it slides down. Even houses and whole groves can die during landslides.