Javad Paktinat, Joseph A. Pinkhouse, Nicholas J. Johnson, Curtis D. Williams, Universal Well Services Inc, Gary G. Lash, State University of New York-College at Fredonia, and Michael A. Forgione, Great Lakes Energy Partners, LLC.

The primary purpose of stimulating fractured shale formations in Northeastern America is to extend the drainage radius by creating a long fracture sand pack that connects natural fractures and increases flow channels to the wellbore. However, most of the fracturing pad fluid leaks off into natural fractures resulting in shorter effective frac lengths and a significant damage zone surrounding the fracture. This is due in part to inadequate fluid loss control properties of the injected fluid and high capillary forces that retain fluid in the formation. Surfactants are used to lower high capillary forces and help well cleanup of the injected fluids. However, many of these additives adsorb rapidly within the first few inches of the shale formations, reducing their effectiveness resulting in phase trapping of the injected fluid.

This study describes the laboratory experiments and field data comparing various surfactants and multi-phase fluid system to determine their leakoff and adsorption properties when injected into a 6 foot laboratory shale packed column. A laboratory comparison study of these systems was used to select additive combinations to apply within the fracturing fluid to restore pad leakoff efficiencies and improve flowback of injected fluid from fractured shale gas wells.

Data collected from various fractured shale formations of Northeastern region confirms experimental shale packed column and core flow investigations.

Reservoirs treated with proposed multi-phase fluid demonstrate exceptional leakoff efficiencies, 50% less skin damage, and higher flow rates when compared with conventional treatments. These investigations and presented data can be used to optimize hydraulic fracturing performance of fractured shale formations.

AAPG Search and Discovery Article #90059©2006 AAPG Eastern Section Meeting, Buffalo, New York