Difference Between Lithosphere and Crust

Lithosphere vs Crust

Earth, which is a spheroid, is not a monolithic, uniform structure, but divided into layers having different characteristics. Starting from the center of the earth, it is the core that is encountered first (3500km radius). Then comes mantle that surrounds this core and has a thickness of 2900km. The surface of the earth down to mantle that literally floats on the mantle is called crust and is made of basalt and granite. Lithosphere is a layer that includes the crust and uppermost portion of asthenosphere. Thus, lithosphere contains the oceanic crust, continental crust, as well as uppermost mantle. It confuses many as to why there are two names for the same layer of earth. Well, it has to do with different ways scientists study earth and its properties. While lithosphere is studied with mechanical properties of earth in mind, crust is studied with a focus on chemical composition of earth. There are some more differences that will be explained in this article.

The word lithosphere comes from lithos, meaning rocks, and sphere, thus, it is the study of rocks that form the surface of the earth and includes the crust, which is the skin of the earth and the uppermost mantle. This layer goes below the surface of the earth to about 70-100km. This is rigid and relatively cool section of earth that is believed to be floating on top of much warmer and molten material that makes lower mantle.

Of the many layers of the earth, crust is the outermost layer and is the skin of earth. Oceanic floor is crust and continental crust as well as mountains is also included in this crust. While the thickness of crust below oceans is just 5-10km, it is as much as 60km under some mountain ranges.

The region below lithosphere is made up of asthenosphere (asthenes means weak). These are rocks that are at a high temperature, and are thus, less rigid and at places even flowing because of high pressure. Thus, crust and upper mantle, that compose lithosphere, float on top of asthenosphere, which remains in a state of continual motion. It is this motion that causes plates of lithosphere to rub against each other. This process is called plate tectonics, and is responsible for many natural disasters such as volcanoes, earthquakes, landslides, and continental drift.

What is the difference between Lithosphere and Crust?

· Crust and lithosphere are names of the outermost surface of the earth, though there are many vital differences between the two.

· The next layer down the crust is the uppermost part of mantle, and the two together make up lithosphere.

· Lithosphere is broken into giant plates that fit in like a jigsaw puzzle. There is continuous movement of these tectonic plates on less dense, almost fluid mantle that makes up asthenosphere. This movement of rocks leads to natural disasters like earthquakes, volcanoes, and landslides.