Hydraulic Fracture

Hydraulic fracturing is creating cracks in the rocks surrounding the borehole, due to the pressure at the well bottom as a result of viscous fluid injection into the rock. The viscous liquid is injected into the well at a rate which ensures the creation of downhole formation cracks. These cracks have vertical and horizontal orientation. The length of the crack sometimes reaches tens of meters; the width of it is usually about few mm or cm. After fracturing a mixture of a viscous liquid with solid particles in it to prevent the closing of cracks under the action of rock pressure is pumped into the well. Hydraulic fracturing of formation is performed in low-permeability formations where the individual zones and intercalations are not engaged in active development which reduces possible oil recovery. Cracks, crossing the poorly drained areas and interlayers provide better production As a result oil is more easily flowing from the formation first into a hydraulic fracture and then to the well, thus increasing oil recovery.
Enhance production/NPV from low-permeability (tight) reservoirs by creating a highly conductive flow path - a hydraulic fracture.

Executed in three stages:

  • 1. A fracturing fluid is injected to create a fracture from the wellbore.
  • 2. Proppants are mixed into the fracturing fluid and pumped into the fracture. Proppant concentration is gradually increased.
  • 3. Fracturing fluid is extracted back, leaving the proppant behind to keep the fracture open and thus a pathway for the gas/oil to flow.