Are The Continents Composed Mostly Of Granitic Rock Or Basaltic

The crust is composed of two basic rock types granite and basalt.

Are the continents composed mostly of granitic rock or basaltic.

The continental crust is composed mostly of granite. The key difference between basalt and granite is that basalt is mostly occurring on ocean floors while granite is in the crust of the earth in all continents. This difference in density allows the continents to float higher on the underlying mantle. Continental crust is typically 40 km 25 miles thick while oceanic crust is much thinner.

They are composed of mostly granitic rocks with an average density of 2 7g cm 3. Compared to the familiar granite of the continents basalt ba salt is darker denser and finer grained. Basaltic rocks of the ocean plates are much denser and heavier than the granitic rock of the continental plates. Because of this the continents ride on the.

Continental crust is broadly granitic in composition and with a density of about 2 7 grams per cubic cm is somewhat lighter than oceanic crust which is basaltic i e richer in iron and magnesium than granite in composition and has a density of about 2 9 to 3 grams per cubic cm. Some of it erupts on land too but to a first approximation basalt is an oceanic rock. All rocks of igneous origin consist of magma or molten earth that finds its way up to. The oceanic crust consists of a volcanic lava rock called basalt.

Why are continents made mostly of granitic rocks and ocean basins mostly of basaltic rocks.