Asthenosphere
The asthenosphere is part of earth's mantle. It's at about 100 km to 350 km under the place where we live in. It is the lower part of the upper mantle, and it's like a hot viscous liquid. It's like a hot, weak material that can break like silly putty. That means it is easily breakable. It is under the lithosphere.
en.wikipedia.org/wiki/Asthenosphere