Temperature, Pressure and Density

Temperature, Pressure, and Density are some of the vital factors that affect the environment and the earth’s interiors. These three factors are interrelated to each other and have individual effects on the layers of earth and even on the environment. Their impacts on the surrounding temperature, underground water labels, and many other factors are also affected. These factors affect the earth’s interior which causes some movements in every layer of earth and we can observe them in the earth’s crust. 

In this article, we are going to discuss the basic structure of the earth first and then proceed with some of the factors that are affecting the different layers of the earth. The factors that will be discussed are Temperature, Density, and Pressure. These three factors are interrelated to each other. It will become easy to understand the factors once the structure is discussed. 

Interior structure of the earth 

The earth consists of mainly three layers: Crust, the outermost layer, Mantle, the second layer, and Core, the innermost layer. 

Crust

It is the outermost layer of the earth that is exposed to nature and humans. It normally has a depth between 9-30 km. The depth of the crust varies from place to place. The depth of crust near the ocean is lower as compared to continental crust. The crust is made of Silica and Aluminum.

Mantle 

It is the second layer of the earth after the crust. The portion where the crust ends and the mantle starts this change is called Moho discontinuity. It is the largest part of the earth with a depth of approximately 3000 km. The constituents of this portion are Silicon and Magnesium. As with the increasing depth the pressure and temperature increase so the material texture is different in the mantle.  

Core 

This is the innermost layer of the earth under high temperature and pressure. The portion where the mantle ends and the core starts is called Guttenberg’s discontinuity. The core is categorized to two parts: outer core and inner core. The texture of the material is different in the two parts. The outer core is in the liquid state and the inner core is in a solid-state. This is because of the difference in temperature and pressure.

Now let’s discuss the effects of Temperature, Pressure, and density of the earth’s interiors.

Temperature 

Temperature increases as we move from the earth’s crust toward the core. There are many observations made that the increase in temperature with depth is faster in some places and slower in some.

Even the rate of increasing temperature changes with depth according to the study. Initially, the rate of change of temperature is around 1-degree Celsius for 33m but as the depth reaches 120 km the rate changes to 12 degrees per km, but on the further increase, the rate of change of temperature decreases to 10 degrees per km. The rate of the change in temperature gradient is not a stiff downfall, it changes with depth. 

Pressure

Like temperature, the pressure also increases with increasing depth. Due to the presence of heavy materials like rocks and metals like Nickel and Iron, the pressure also increases. The pressure down there is 5 to 6 million times the atmospheric pressure. At such a tremendous pressure along with the high temperature the materials there tend to melt. They are basically in a plastic state that the deformation caused to those metals due to the immense stress is permanent. For these reasons, the outer part of the core is in the molten state, as metals melt on the application of high temperature and pressure according to physics and material science. 

Density

The least density is found in the earth’s crust and it gradually increases toward the center, that is the mantle is denser than the crust and the core is the densest part of the earth. As there are many metals present within the earth due to tremendous temperature and pressure they tend to melt and move towards the center that’s the reason why the core is in a molten state initially. As the metals accumulate there the core becomes denser and denser. The continental crust is less dense than the oceanic crust. With the help of density, scientists can tell which tectonic plate will float and sink. Density plays a vital role in formation of new earth crust and also can tell which portion of earth crust will sink.

Conclusion

In this article we have told the temperature, pressure and density of earth’s interiors. This article also mentions effects of these factors on different layers of the earth. The depth of the crust is not the same in every place. The rate of change of temperature changes with change in depth. The density plays some vital role in the interiors as well as in the environment; everything has been discussed in this article. Impact of the factors on metals leads to melting them and thus increasing the density at the core. Overall all the three factors Temperature, Pressure and density affects the earth self in some way. The depth of different layers is also mentioned here.