.jpg "Gaget at Tignay")
When you try to observe our surroundings, you probably see vast expansion of land or water. You may probably think as well about what can be found beneath the ground, or what it looks like above the sky.
There are four layers of the Earth, actually. Each of these parts play a very special specific function that makes life on Earth possible.
{tocify} $title={Table of Contents}
The Earth's Structural Layers
Just imagine Earth as a giant sphere egg. The outermost layer is called crust. Did you know that it's where we live?
As you go deeper, you'll see thick and hot mantle. If you ever wonder what would happen if there's an activity in it, you may feel earthquakes as it drives tectonic plates.
When you go beyond deep inside, the two more layers which we don't see but have very crucial rule in our everyday life are the outer core and inner core.
Now, let’s break it all down so you can understand more about their significance.
4 Layers of the Earth
There are four main structural layers of the Earth. They differ on physical characteristics and composition. Here's a closer look to each of them.
1. Crust
Think of an egg which was boiled. The shell, which is the topmost layer, is the crust.
Description
It is known as the outermost, solid layer of the Earth.
State
It is solid and rocky.
Composition
The crust is divided into oceanic crust and continental crust. The former thinner but denser, while the latter is thicker.
Depth
This varies but for oceanic crust, it ranges from 5-10 km thick. As for continental crust, the thickness ranges from 25-70 km.
Did you know?
This is layer where we are living. It is where we see farms, build cities, and walk every day. Compared to the rest of Earth's layers, it’s thinner.
2. Mantle
Just below the crust, it is a thick layer with molten composition but not liquid. Like in a boiled egg, the white portion after the shell represents the mantle.
Description
The upper mantle, otherwise known as asthenosphere, is not rigidly solid. It is somewhat molten, but take note that it is not flowy as a liquid. Its viscosity is super high, which simply means it flows very slowly.
Depth
Its distance from the crust and the outer core measures approximately 2,900 kilometers or 1,802 miles.
Did You Know?
The mantle is considered as the Earth’s largest layer. It drives movement of tectonic plates above it that is why we feel earthquakes and see eruption of volcanoes.
Read more:
- Pacific Ring of Fire, Pugon nga ba ng mga Aktibong Bulkan?
- The 8 Parts of Speech, Their Definition, Examples, and Rules
- Guide in Mastering the Rules of Integers
3. Outer Core
Although primarily composed of iron and nickel, the outer core is in liquid form with temperature ranging from 4,500 to 6,000°C.
Just imagine what would happen to your finger if you dip it in this layer.
Description
The outer cores is a liquid layer that is responsible for generating Earth's magnetic field. Such field is known for its responsibility it deflecting harmful solar radiation and enabling compass navigation so you won't get lost.
Depth
With a massive thickness of 2,260 km, it lies approximately 2,889 km beneath the Earth's surface.
Did You Know?
The age of Earth and its core is different. Before it became the Earth we are living in, it was once just a ball of hot rock. The latter was started forming due to its temperature that heated to the melting point of iron. What's even astonishing is that its hottest temperature is 6,000° Celsius, which is as hot as the surface of the sun.
4. Inner Core
Composed of mostly iron (Fe), this layer is molten not liquid. What causes this layer to not melt is due to its intense pressure.
Description
This layer is about 1,230 to 1,530 km when it comes to thickness. It grows about 1 mm per year. It's gonna take billions of years before the outer core solidify as part of the inner core.
Depth
Below the surface of the earth, the inner core is about 5,100 km underneath.
Did You Know?
The inner core has a slightly different rotation. Every thousand years, it takes extra rotation as it is faster.
The Bottom Line
Science isn't just cool. It's also amazing and full of interesting stuff. It answers several questions in our minds such as the discussion we just had today about the Earth's layers.
Although some can't be explained fully and haven't been absolutely proved yet, its significance continue to grow as scientists become more and more curious each day.
Reference
- https://education.nationalgeographic.org/resource/core/