The Interior Layers of Earth

Although we cannot directly see the interior of the Earth, scientists use instruments to collect data about it. These data are used to make a model of what the inside of the Earth is like.

The Earth is made up of three main layers. At the center is a dense core. The core is subdivided into two sections: an inner layer composed of solid iron and nickel, surrounded by an outer layer of melted iron and nickle. Outside the core is the mantle. The mantle is made up of liquid and solid rock that moves and churns. the outermost layer of the Earth is the crust. Compared to the other layers, the crust is very thin and cold. The continents and oceans are part of the crust.

The most abundant element inside the Earth is iron.

This week we will focus on the movement of Earth's crust and the forces that make it happen. We will look at the theory of Plate Tectonics and the individuals that made the discoveries that developed the theory.

Homework # 6 is due Monday, March 16, 2009 (Marking Period 2 begins today).

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