How are the following rocks formed?
a) Igneous rocks
b) Sedimentary rocks
c) Metamorphic rocks
Answers
following rocks are formed by **************************************
a) In essence, igneous rocks are formed through the cooling and solidification of magma ( or lava). As hot, molten rock rises to the surface, it undergoes changes in temperature and pressure that cause it to cool, solidify, and crystallize.
b) Sedimentary rocks are formed when sediment is deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension. This sediment is often formed when weathering and erosion break down a rock into loose material in a source area.
c) Metamorphic rocks are formed from other rocks that are changed because of heat or pressure. They are not made from molten rock – rocks that do melt form igneous rocks instead. Earth movements can cause rocks to be deeply buried or squeezed. As a result, the rocks are heated and put under great pressure .