This model shows Earth’s internal structure. It shows the Earth’s crust, mantle, the outer centrosphere and the inner centrosphere. The different layers are labelled for easy identification. A knowledge of earth’s interior is essential for understanding plate tectonics. The layers of theEarthcan be defined by their chemical and their rheological properties. Earth has an outer silicate solid crust, a highly viscous mantle, a liquid outer core that is much less viscous than the mantle. As well as a solid inner core. Each of the layers differ chemically and mechanically. The further you get to the core of the Earth, the hotter it gets. The Earth model is 32cm in diameter and is supplied on a stand.