Strain

Strain

The deformation or change in shape of a material (such as rock) specifically in response to applied stress (pressure). While stress is the force per unit area exerted on a rock, strain describes how that rock physically responds to the stress. 

There are three main types of strain:  

1. Elastic Strain – temporary deformation when stress is applied to a material, but the material returns to its original shape once the stress is removed. 

2. Ductile (Plastic) Strain – permanent deformation that occurs when stress exceeds a material’s elastic limit, causing it to flow or bend without breaking.  

3. Brittle Strain – deformation that results in the breaking or fracturing of a material, typically occurring when the stress exceeds the material’s strength.