GEOLOGY

Detailed explanation-1: -At its site of generation, magma is lighter than the surrounding material, and consequently it rises as long as the density contrast between magma and surrounding cooler rocks continues. Eventually, magma either solidifies or forms reservoirs at some depth from the Earth’s surface, or it erupts.

Detailed explanation-2: -The lighter silica rich rocks that compose the continental crust form by partial melting of pre-existing denser basaltic rocks. When you partially melt a basalt, the liquid is richer in silica, thus it is less dense.

Detailed explanation-3: -Magma has a lower density than the surrounding solid rocks. The principle of density states that an object or body with a lower density rises up and above an object with a higher density.

Detailed explanation-4: -Magma is less dense than the surrounding rock which causes it to rise. When magma reaches the surface it is then called lava and the eruptions of lava and ash produce volcanoes. The lava that reaches the Earth’s surface will harden and become igneous rock.

Detailed explanation-5: -This happens because different minerals have different melting temperatures. The melt is less dense than the surrounding rock, and will percolate upward without the source rock having melted completely. The result is magma with a different composition than the original rock.