What Does Fracture-Close Pressure Mean?
Fracture-close, also known as fracture-closure pressure, is the pressure at which a fracture closes without the presence of a proppant or the minimum pressure required to keep the fractures open. At closure pressure, the width of the fracture becomes zero. Fracture pressure on the other hand is the pressure required to make a fracture in a rock.
The pressure required to create a fracture is equal to the pressure required to resist stress in a rock perpendicular to the fracture and hence, the closure pressure is equal to the minimum in-situ stress.
