A Peek Inside Earth
The crust is the solid outer layer of Earth. This layer is the thinnest layer of Earth and is much cooler than the other layers. The first layer consists of about 10 miles of rock and loose materials. Underneath the continents the crust is almost three times as thick as it is under the oceans. The crust is broken into many large pieces called tectonic plates. Scientist believe these plates "float: and move around very slowly on the mantle.
Traveling beyond the Earth's crust, we next encounter the mantle. The mantle extends to a depth of approximately 1,800 miles and is mostly made of iron and magnesium. The mantle's temperature of about 5400 degrees Fahrenheit can melt rocks. This melted rock flows like a stiff liquid. The rock in the lower mantle, close to the core, is solid because of the pressure pushing down on it.
The Outer Core
The outer core is approximately 1350 miles thick and is a combination of mostly molten iron and nickel. Molten describes materials that change to a liquid form when exposed to extreme amounts of thermal energy. The temperatures range from 7,000-9,000 degrees Celcius. The outer core is less dense than the inner core and therefore flows around the inner core. The movement of the melted metals creates Earth's magnetic field.
Earth's Inner Core
The deepest layer in Earth is the inner core. It is located at the center because it contains the densest material of all of Earth's layers. The inner core is solid and mostly made of iron. Its extremely hot temperature is 11,000 degrees Fahrenheit. This layer is approximately 775 miles thick.