Mighty rocks can fall apart and be broken to minute pieces. Indestructible granite is no exception to this. As time pass by, all rocks decay and break up into even smaller fragments by a process known as withering. But how do rocks wither?
One important reason is water. Water picks up acid forming substances from air and soil making it slightly acidic. This acidic water seeps through the rock slowly and starts to attack. The rock gradually gets corroded. In some cases, such as with limestone, rock becomes completely dissolved. Rocks slowly start to disintegrate because of the decomposing minerals within them. This process is called chemical weathering.
There is yet another kind of weathering caused by physical forces. Here again water plays the major role. We know that when water freezes, it expands. Thus, when it seeps through the cracks of rock and then freezes, it tries to force the rock apart. Ice that gets formed on the cracks chips off small flakes of rocks. It can sometimes loosen huge pieces and send them tumbling down.
Roots of trees and temperature changes can also cause withering of rocks. Extreme climatic conditions like alternating hot days and cold nights can also rupture rocks.
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