Hint: The Sial layer is the upper layer of the Earth's crust. It is absent in wide oceanic basins because of which it is known as the continental crust.

Where is sial found in the earth?

The sial is the part of the crust that is above water. It's a continental plate floating over the globe. Right underneath the sial is the sima. The sima is the layer of the Earth's crust that covers the entire planet.

Why is sial called the granite layer?

i. A layer of rocks, underlying all continents, that ranges from granitic at the top to gabbroic at the base. The thickness is variously placed at 30 to 35 km. The name derives from the principal ingredients, silica and alumina.