Rocks undergo deformation when stress (force) is applied to them. Identify the ways in which rocks deform and the chemical and physical factors that are involved in the deformation process

Question

Include in your answer a description of compressional and tensional forces.

Answer 1

There are three types of deformation that rocks can undergo elastic, plastic and brittle. Deformation is when rock is under strain and change in size, shape, or volume of a material. Elastic is when the rock is compressed and then over time the rock starters to return to its previous shape. Elastic deformation is a change in shape of a material at low stress that is recoverable after the stress is removed. This type of deformation involves stretching of the bonds, but the atoms do not slip past each other and the rock comes back to its original size and shape. Plastic deformation is when the stress is sufficient to permanently deform the rock. This occurs when the rock is too weak and the stress placed on it is too high over a long period of time. The force needed to break the atomic bonds is very great. Brittle deformation occurs when the stresses placed on the rock large extremely large. This deformation causes the stiff rock to break under the pressure. Tensional forces pulls the rock apart as if being ripped apart. Compressional forces squeeze the rock tighter together. There are many factors that contribute too the deformation of the rock. Water is on of the factors rocks that are wet are softer and will deform with lower amounts of strain and temperature. Brittle rocks tend to fracture along joints where they are weaker because it creates water and chemical channels to induce weathering.