Studying the earth's interior can help us to understand earthquakes, volcanoes, plate tectonics and more about the inner earth’s natural processes. In general the earth's interior has been sorted by Gravity. Heavier elements like iron tend to sink toward the center or core of the earth. Lighter materials, the silicates, oxygen compounds and water have risen to become part of the crust. This action has created distinct layers within the earth and is still in process today. The Inner Earth is composed of three main parts; the crust, the mantle, and the core as shown in the diagram of the earth's interior below:
* The Crust - silicate rocks, primarily granite and basalt * Oceanic Crust - mostly basalt
* Continental Crust - igneous, metamorphic, and sedimentary rocks * The Mantle - iron and magnesium rich silicate rocks
* Upper Mantle (Asthenosphere)
* Lower mantle (Mesosphere)
* The Core - iron nickel alloy
* Outer core
* Inner core
The crust of the earth is very slowly growing thicker. Volcanic activity is continually adding mass to the crust. Though the crust is solid it is made up of about 12 plates. They are called Tectonic Plates. These plates are in constant motion. The movement is caused by convection currents in the mantle. The movement is very slow, averaging about 2 inches a year. This is about like the growth of your fingernails. * The crust is about 0.5 % of the earth’s total mass.
* The crust is made up of silicate rocks such as granite and basalt. * The continental crust is much thicker than the oceanic crust as shown here in the diagram of the earth's crust. Oceanic crust - The crust under the oceans is about 10 km thick and is generally made up of rock rich in iron and magnesium. These are primarily basalt formed by volcanic action at the mid ocean ridges. The oceanic crust is denser than continental crust. Continental crust (continental...