Soil Formation

Soil is formed by the combination of physical , chemical and biological processes over a long period of time . Rocks under go through a process of expansion and contraction in which they expand during the day and contract during the night due to the constant rise and fall temperature. However not all parts of a rock undergo expansion and contraction at the same rate, resulting in the formation of cracks . Gradually , these cracks cause the rocks to break down into smaller pieces . With time , these smaller pieces convert into particles and form soil . Water plays an important role in soil formation. Water that gets collected in the cracks of rocks , sometimes freezes which helps widen the cracks. Also , flowing water helps in wearing down of the rocks overtime, which results the formation of soil. Strong blowing winds also rub against rocks and help in wearing them down .