Using flow induced stresses for steering of injection fractures

Both horizontal and vertical rock stress magnitudes are substantially affected by pore pressure gradients generated by production from and water injection into low permeable chalk fields. This is confirmed by solid mechanics stress analyses and by observing fracture propagation in developed fields. Stress changes generated around horizontal injectors placed centrally between two parallel horizontal producers are considered in detail in this paper. It is shown that overburden and sideburden stresses may be altered and controlled to confine propagation of fracturing along the length of a central openhole horizontal injection well. It thereby becomes possible to establish a line drive development based on injection of water at fracturing conditions at reduced risk of premature water breakthrough (patent pending).