Interior Layers of Earth

1. Interior Layers of Earth

2. The Earth has three major layers: • 1) The Core: consists of to two layers • a) a solid Inner Core made up primarily of solid iron and • nickel; this layer measures about 1250 km thick and is • the hottest at an average of 5000°C to 7000°C • b) a liquid Outer Core made up primarily of liquid iron and • nickel; this layer measures about 2200 km and is also • very hot at around 4000°C to 6000°C

3. The Earth has three major layers: • 2) The Mantle: consists of several layers such as the lower mantle, upper mantle and asthenosphere. Combined, the mantle is approximately 2900 Km thick. • - The Asthenosphere is dynamic in that it is capable of flow, this is where convection currents that move the crust above it, occur.

4. The Earth has three major layers: • 3) The Crust: consists of i) the ocean floors and ii) the continents. This is the thinnest layer of the Earth at 30 km to 100 km thick. This layer is fractured into pieces called “plates” which move over the Asthenosphere, creating mountains, volcanoes, earthquakes, deep ocean trenches, rift valleys, etc.

5. Differentiation • The Earth’s early formation through the process of accretion made all of these layers possible. As a hot, molten body in its early formation, heavier elements began to differentiate from surrounding lighter elements. • - heavier elements like iron and nickel settled at the center becoming the core of the Earth • - lighter silicate materials rose to the surface and become the crust of the Earth