Are The Continents Composed Mostly Of Granitic Rock Or Basaltic

While the ocean basins are composed of mostly basaltic rocks with an average density of 3 0g cm 3.

Are the continents composed mostly of granitic rock or basaltic.

They are composed of mostly granitic rocks with an average density of 2 7g cm 3. The continental crust is composed mostly of granite. 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. The oceanic crust consists of a volcanic lava rock called basalt.

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 crust is composed of two basic rock types granite and basalt. Basalt is the dark heavy volcanic rock that makes up most of the world s oceanic crust.

Basaltic rocks of the ocean plates are much denser and heavier than the granitic rock of the continental plates. This difference in density allows the continents to float higher on the underlying mantle. Compared to the familiar granite of the continents basalt ba salt is darker denser and finer grained. Continental crust is typically 40 km 25 miles thick while oceanic crust is much thinner.

Earth contains three kinds of rocks namely igneous rocks sedimentary rocks and metamorphic rocks basalt and granite are two types of igneous rocks.