It is well understood that the key objective of hydraulic fracturing in tight gas reservoirs is the creation of effective fracture length. It is also understood that conventional crosslinked gel fracture stimulations do not necessarily create the desired fracture dimensions. The potential reasons for the shorter than desired fracture lengths are numerous, with the most likely being excessive fracture height growth and poor fracture fluid cleanup.
Reducing net treating pressure with a treated water fracture stimulation may limit height growth. In addition, elimination of polymer by fracture stimulating with treated water may provide more effective, "cleaner" fractures. The use of treated water, with its poorer proppant transport properties, however, may also result in a shorter propped fracture.
This presentation will first present an historical perspective on the use of treated water as a fracturing fluid and high light the risks and rewards associated with its application. Production, geomechanical, and treatment data will be reviewed, and guidelines for the application of the water frac technology will be discussed. These guidelines will provide a means for designing an effective water fracture stimulation which minimizes the risks associated with its use. In addition, several basic questions will be addressed. These include: Do water frac stimulations work? If so, why? If not, why not? And what would I do if it was my well?