Since ancient times, it has intrigued what is below the earth's crust and has wanted to find an explanation. Where do minerals come from? How many types of rocks are there? What are the parts of the Earth?
These are many of the questions that have been asked throughout history. If you want to know more about the parts of the Earth here we tell you more about them.
The part of geology that studies the structure of the Earth and the different layers is the internal geodynamics. Our planet is made up of various elements that make life on Earth possible. The three elements are: solid, liquid and gas. These elements exist in different layers of the Earth.
There are many ways to classify the parts of the Earth. In one classification, they are called espheres. These include the Atmosphere, the Hydrosphere, and the Geosphere. The Geosphere brings together all the structures and different internal layers of our planet. The layers are divided into two layers: the outer layer and the inner layer. In our case, we will focus on the inner layers of the Earth, that is, the surface of the Earth will be the beginning.
parts of the earth
To begin to describe the parts of the Earth, we must make two distinctions. First, standards were established for the chemical composition of the different layers of the Earth. According to the chemical composition, we find the crust, the mantle and the core. This is called a static model. Another criterion is based on the physical properties of the layers or also called mechanical behavior model. Among them we find the Lithosphere, Asthenosphere, Mesosphere and Endosphere.
But how do we know where a layer begins or ends?
Scientists have found different ways to understand the types of materials and distinguish layers across discontinuities. These discontinuities are regions of the Earth's inner layer where the type of material contained in that layer suddenly changes., that is, its chemical composition or the state in which an element is found (from solid to liquid). First we are going to classify the layers of the Earth based on the chemical model, that is, the layers of the earth will be: Crust, Mantle and Core.
Earth's crust
La Cortex It is the outermost layer of the earth. Has a average density of 3 gr/cm³, who it is only 1,6% of the total volume of the Earth. This is divided into two distinct regions: continental crust and oceanic crust.
Continental crust
The continental crust It is thicker and more complex in structure.a. It is also the oldest bark. It represents 40% of the earth's surface. It consists of a thin layer of sedimentary rocks, of which clay, sandstone, and limestone are the most prominent. They also have silica-rich plutonic igneous rocks similar to granite. Interestingly, most of the geological events that have occurred in Earth's history are recorded in the rocks of the continental crust. This is well known because rocks have undergone many physical and chemical changes throughout history. This is evident in the mountains, for example, where we can find ancient rocks that can be up to 3.500 billion years old.
oceanic crust
On the other hand, we have the oceanic crust. It has a smaller thickness and a simpler structure. It consists of two layers: a very thin layer of sediment and another layer of basalt (which are igneous volcanic rocks). This bark is younger, because basalt has been found to form and break constantly, so the rocks in the oceanic crust are no more than 200 million years old. At the end of the cortex is the mold discontinuity. This discontinuity is what separates the crust from the mantle. It is located about 50 kilometers deep.
Manto
The mantle is one of the parts of the Earth that extends from the bottom of the crust to the outer core. It starts behind the Moho and is the largest layer on the entire planet. That's the 82% of the total volume of the Earth and 69% of its total mass. In the mantle there are two layers separated by secondary Repetti discontinuities. This discontinuity is located at a depth of about 800 kilometers and is where the upper mantle separates from the lower mantle. In the upper mantle we find the "layer D". This layer is found at a depth of about 200 kilometers and is characterized by 5% to 10% partial melting. This causes heat to rise from the core through the mantle. As the heat increases, the rocks in the mantle get hotter, sometimes rising to the surface and forming volcanoes. These are the so-called "Hot spots"
The composition of the mantle can be known by these tests:
- There are two types of meteorites: the first is formed by peridotite and iron.
- Existing rocks on the surface of the Earth that have been removed from the mantle due to tectonic movements.
- Volcanic Chimneys: They are very deep circular holes through which the magma rises and exposes them. It can have a length of 200 kilometers.
- All the seismic wave shortening tests as they pass through the mantle they suggest that there is a phase transition. Phase transitions include changes in mineral structure. At the end of the mantle we find the Gutenberg discontinuity. This discontinuity separates the mantle from the core and sIt is located about 2.900 kilometers deep.
Core of the Earth
It is the deepest part of the earth. It extends from the Gutenberg discontinuity to the center of the Earth. It is a sphere with a radius of 3.486 kilometers, so its volume is 16% of the total volume of the Earth. Its mass is 31% of the total mass of the Earth because it is composed of very dense material. In the core, the Earth's magnetic field is created by convection in the outer core, which melts around the inner core, which is solid. Its temperature is very high, around 5000-6000 degrees Celsius, and the pressure is equivalent to one to three million atmospheres.
Divided into an inner core and an outer core, the difference being given by the secondary Vicht discontinuity. El Outer core, whose depth varies between 2.900 and 5.100 kilometers, is molten. The inner core, on the other hand, extends from a depth of 5.100 kilometers to about 6.000 kilometers from the center of the Earth, and it is solid.
This is composed primarily of iron, 5-10% nickel, and smaller proportions of sulfur, silicon, and oxygen. The tests that help to know the nuclear components are:
- very dense materials, for example. Due to their high density, they remain in the inner core of the Earth.
- iron meteorite.
- The lack of iron on the outside of the crust. This tells us that the iron must be concentrated inside.
- Along with the iron inside the core, it forms Earth's magnetic field.
This classification comes from a model that takes into account the chemical composition of different parts of the planet and the elements that make up the layers of the planet. Now we will understand the division of the layers of the Earth from the point of view of the mechanical behavior of the Earth, that is, from the point of view of the physical properties of the materials that compose it.
Parts of the Earth according to the mechanical model
In this model, the layers of the earth are divided into: Lithosphere, Asthenosphere, Mesosphere and Endosphere.
Lithosphere
It is a rigid layer about 100 kilometers thick which includes the upper layers of the crust and the mantle. This rigid layer is the lithosphere that surrounds the Earth.
Asthenosphere
Is the plastic layer corresponding to most of the upper mantle. There is convection in it and it is in continuous motion. It is of great importance in tectonics. This movement is caused by convection, a change in the density of the material.
Mesosphere
It is found at a depth of 660 kilometers and 2.900 kilometers. It forms part of the lower mantle and part of the outer core of the Earth. Its extremums are given by Wiechert discontinuities.
Endosphere
Includes the inner core of the Earth aforementioned. As you can see, scientists have been studying the interior of the Earth through various tests and trials to learn more and more about the planet we live on.
As you can see, scientists have been studying the interior of the Earth through various tests and trials to learn more and more about the planet we live on. To compare what little we know about the interior of the Earth, we need only imagine the Earth as an apple. Well, with our advanced technology, the deepest drilling depth that has been achieved is about 12 kilometers. Comparing the Earth to an apple is as if we only peeled off the last layer of the entire apple, and the seed in the middle is equivalent to the core of the Earth. I hope this information has been helpful.