The Mantle
The mantle is the second layer of the Earth. It's the thickest layer in Earth's structure and has two parts; the upper mantle and the lower mantle. The upper mantle is about 25 km deep and is the most active of the 2 parts. The upper mantle is could be made of peridodite, and is in a liquid state. The lower mantle is right beneath the upper mantle, and is about 2855 km deep. The lower mantle is probably made of silicon, magnesium, and oxygen. Although, scientists can't know for sure. Together, both the upper and lower are almost 3000 km deep! The mantle moves sluggishly and is like hot syrup, its temperatures range from 1000 degrees Celsius, to 4000 degrees Celsius!