Earth has a layered structure. Main distinctive layers of the earth.
Figure: Earth Internal Structure
o The depth of crust ranges from 5Km to 70km.
o It is very thick on the land (continental crust and thin at the bottom of the (oceanic crust).
o The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into tectonic plates.
o It is the thickest layer and its average thickness is 2850Km.
o It contains most of the mass of the earth.
o Mantle comprises nearly 84% of the Earth's volume and 67% of its mass.
o The lowest part of the mantle next to the core-mantle boundary is known as the D layer
o Although solid, the high temperatures within the mantle cause the silicate material to be sufficiently ductile that it can flow on very long timescales.
o Convection of the mantle is expressed the surface through the motions of tectonic plates.
Figure: Structure of the Earth
Core
o The innermost part of the earth is called as core.
o Core's composition is predominantly iron. The core is thus believed to largely be composed of iron (80%), along with nickel and one or more light elements.
o As a result taken as a whole, the Earths chemical composition by mass iron has the highest percentage.
o The liquid outer core surrounds the inner core and is believed to be composed of iron mixed with nickel and trace amounts of lighter elements.
o The Earth's main magnetic field is associated with electric currents in the molten outer core.
Interesting Inner Core Facts: The temperature of the inner core is believed to be approximately 5400 degrees Celsius, or 5700 Kelvin. This heat is caused by three elements: residual heat from the formation of the earth, gravitational forces from the moon and the sun, and and radioactive decay of earth's inner elements.
Figure: Earth Internal Structure
Crust
o The outermost layer which we can touch, dig and explore is called Crust.o The depth of crust ranges from 5Km to 70km.
o It is very thick on the land (continental crust and thin at the bottom of the (oceanic crust).
o The lithosphere, which is the rigid outermost shell of a planet (the crust and upper mantle), is broken up into tectonic plates.
Mantle
o Mantle is the second distinctive layer of the earth.o It is the thickest layer and its average thickness is 2850Km.
o It contains most of the mass of the earth.
o Mantle comprises nearly 84% of the Earth's volume and 67% of its mass.
o The lowest part of the mantle next to the core-mantle boundary is known as the D layer
o Although solid, the high temperatures within the mantle cause the silicate material to be sufficiently ductile that it can flow on very long timescales.
o Convection of the mantle is expressed the surface through the motions of tectonic plates.
Figure: Structure of the Earth
Core
o The innermost part of the earth is called as core.
o Core's composition is predominantly iron. The core is thus believed to largely be composed of iron (80%), along with nickel and one or more light elements.
o As a result taken as a whole, the Earths chemical composition by mass iron has the highest percentage.
o The liquid outer core surrounds the inner core and is believed to be composed of iron mixed with nickel and trace amounts of lighter elements.
o The Earth's main magnetic field is associated with electric currents in the molten outer core.
Interesting Inner Core Facts: The temperature of the inner core is believed to be approximately 5400 degrees Celsius, or 5700 Kelvin. This heat is caused by three elements: residual heat from the formation of the earth, gravitational forces from the moon and the sun, and and radioactive decay of earth's inner elements.
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