What are the four major divisions of Earth?
The four major divisions of earth inside the earth are: the crust, the mantle, the outer core, and the inner core. Some of these have sub-divisions as well.
The crust is the landmasses and ocean floors we can view and experience.
Below the crust is the mantle which is a flowing plastic material (between solid and liquid) that continuously reshapes the crust through earth quakes, volcanoes, and shifting entire continents.
The outer core is a mass of molten metal, mostly iron which spins around the inner core, resulting in the earth's magnetic field, which keeps us safe from bombardment by cosmic rays.
The inner core is the dynamic solid center of the earth that maintains our steady daily rotation and tilt that results in our seasons.
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