Name and describe two types of mechanical weathering.

Mechanical: humans breaking up rocks with equipment in quarrying and stone mining operations breaks rock down 
also, rocks being washed downstream by a strong river current: the current wears them down and breaks them apart as they collide with other river rocks 

Chemical: rainwater, which is mildly acidic, can slowly cause the chemical bonds in a rock's minerals to lose their cohesiveness and break down 
Another example is the release of extremely acidic or alkaline compounds from under the Earth, usually in hydrothermal or volcanic activity. These corrosive chemicals can interact chemically with extant rock formations, weathering or even dissolving them

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