ABSTRACT
The basis of Amoco's fracturing design philosophy has changed significantly since 1978 with a resulting marked increase in treatment efficiency and effectiveness. This change has resulted from a coordinated development of field research programs and analytical studies of the fracturing process. An important integrating part of these investigations was the development of a basis for interpreting the fluid-pressure response during and after a treatment and the resultant implications for subsequent treatment design. Principally, this work shows that excessive pressure due to fluid flow in the fracture can cause problems such as excessive height growth and screen-outs which reduce the potential fracture penetration. A primary design change was to limit the pressure through control of the fluid viscosity.
This paper reviews the procedures for analyzing, modeling and interpreting fracturing pressure, the benefits and examples of pressure controlled designs, and the bases for special considerations in fluid, proppant, and pumping schedules to successfully execute controlled pressure designs.