Earth comprises four separate layers. Most of the geologist believes that as the Earth cooled, the heavier and the denser material sank into the centre, and the lighter ones rose towards the top. Due to this, the outermost layer is made of the lightest materials such as rocks and granites and the innermost layer consists of nickel and iron. Let’s discuss different layers of earth.
Different Layers of the Earth
The inner core, the outer core, mantle and crust are the four layers of earth
The Inner Core
It is the centre and the hottest layer of the Earth. The inner core is solid and made up of iron and nickel with temperature up to 5,500oC. Due to its immense heat energy, the inner core is more like the engine room of the Earth.
The Outer Core
The outer core of the Earth is similar to a very hot ball of metals, whose temperature is around 4000 oF to 90000F. It is so hot that the metals inside are all in the liquid state. The outer core is located around 1800 miles under the crust and approximately 1400 miles thick. It is composed of metals such as iron and nickel. The outer core surrounds the inner core.
The inner core has pressures and temperatures so high that the metals are squeezed together and not able to move like a liquid, but are forced to vibrate instead of solid.
Mantle is the widest section of the Earth. Its thickness is approximately 2,900 km. The mantle is mainly made up of semi-molten rock known as magma. The rock is hard in the upper part of the mantle, but lower down the rock is softer and begins to melt.
The mantle is located directly under the Sima. The mantle consists of very hot and dense rock. This layer of rock flows like asphalt under heavy weight. This flow is because of the greatest temperature differences from the bottom to the top of the mantle. The reason behind the plates of the Earth move is the movement of the mantle. Its temperature varies between 1600 oF at the upper part to 4000 oF near the bottom.
The crust is the outer layer where we live. The thickness is around 0-60 km. It’s a solid rock layer divided into two types:
- Continental crust covers the land and,
- Oceanic crust covers water
The crust is the most widely studied and understood. Mantle is hotter and capable of flowing. The outer and inner core are much hotter with great pressures that you can be squeezed into a ball smaller than a marble if you are able to go in the center of the Earth.
Watch this video on layers of earth with engaging animations and understand the composition of each of these layers better
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