The Earth’s Mantle
Traveling beyond the Earth’s crust, we next encounter the mantle. The mantle extends to a depth of approximately 1,800 miles (2897km), and is made of a thick, solid, rocky substance that represents about 85% of the total weight and mass of the Earth.
The first 50 miles (80km) of the mantle are believed to consist of very hard, rigid rock. The next 150 miles (241km) or so are believed to be super-heated solid rock that due to the heat energy is very weak. Below that for the next several hundred miles, the Earth's mantle is believed to once again be made up of very solid and sturdy rock materials.