The Layers of the Earth
DeQuinta Pryor
6th Grade Science
6.E.2.1 Summarize the structure of the earth, including the layers, the mantle and core based on the relative position, composition and density.
There are four main layers of the earth. They are the inner core, the outer core, the mantle, and the crust. Some resources just list the core, mantle, and crust, or break the mantle into two sections. Each layer is different in density and what it is made of known as composition.
Inner Core
The inner core is the inner most layer of the earth. The pressure from the other layers causes the inner core to be solid and the most dense. It is composed of mostly nikel.
Outer Core
The outer core is the only liquid layer. It is made of iron and nickel.
The Mantle
The mantle is the thickest layer. It is not liquid or solid but described as plastic like. The mantle has two sections. The upper mantle, also called the asthenosphere, is made of flowing hot rocks called molten.
The Crust
The crust is the outer most layer and thinnest. There are two types of crust; the oceanic and the continental crust. The crust and the upper part of the mantle together are called the lithosphere.