Earth is made up of layers. Most of these layers are made up of solid of partly melted rock. The layers closest to the middle of the Earth are mostly of a mixture of metals. Each layer has a different thickness.
The outer layer, or crust, is much thinner than the other layers. The crust is nearly all solid rock. Under the continents, the average thickness of the crust is about 40 km ( 24 mi ). Under the mountains, it may be as much as 70 km ( 42 mi ). The crust is thinner under the oceans. The ocean floor crust has a thickness of about 7 km
( 4 mi ).
The layer just below the Earth's crust is the mantle. The mantle is about about 2900 km ( 1800 mi ) thick. it is the thickest layer. The solid upper part of the mantle joins with the crust to form the lithosphere. Below the lithosphere, much of the rock in the mantle is partly melted. This material can flow very slowly. The hard lithosphere can be thought of as " floating " on the lower mantle.
At the center of Earth is called the core. The core is divided into 2 layers- the outer core and the inner core. The outer core is about 2200 km thick. It is the only layer that is all liquid. The inner core is about 1200 km thick. It is even hotter than the outer core. Both the outer core and inner core are probably made up of very hot iron and nickel. High pressure deep inside Earth keeps the rocks form melting.
( 4 mi ).
The layer just below the Earth's crust is the mantle. The mantle is about about 2900 km ( 1800 mi ) thick. it is the thickest layer. The solid upper part of the mantle joins with the crust to form the lithosphere. Below the lithosphere, much of the rock in the mantle is partly melted. This material can flow very slowly. The hard lithosphere can be thought of as " floating " on the lower mantle.
At the center of Earth is called the core. The core is divided into 2 layers- the outer core and the inner core. The outer core is about 2200 km thick. It is the only layer that is all liquid. The inner core is about 1200 km thick. It is even hotter than the outer core. Both the outer core and inner core are probably made up of very hot iron and nickel. High pressure deep inside Earth keeps the rocks form melting.