Answer:
The ductile and the elastic deformation are two types of deformations that occurs in the earth's crustal rocks and the rocks of upper portion of the upper mantle.
The ductile deformation usually refers to the property of the rock by which it deforms into large strain without breaking the rocks. This occurs at a greater depth, and here the strain remains unchanged after the stress is being removed.
On the other hand, elastic deformation refers to the type of deformation in which the rocks have the ability to regain its strain at a low stress after the removal of the stress. This change that occurs in this region are temporary as it comes back to its original shape.