Damage to natural fractures have been found to occur as a result of conventional completion techniques previously employed at the DOE Multiwell Experimental (MWX) Site. In an attempt to understand some of the damage mechanisms and find mitigating techniques that could be practically employed, a series of rather unconventional completion procedures were performed. These procedures were designed to utilize gases rather than aqueous-based fluids during the perforating and breakdown/ microfracturing process and were performed in several differing reservoirs. Previous tests at the MWX underscored the impairment to natural fracture flow capacity that resulted from liquid invasion during perforating, breakdowns or large scale stimulation. Thus, the use of gases during the initial connection into the naturally fractured reservoirs at the MWX was considered a natural starting point.

The completion techniques that were tested and that will be discussed employed nitrogen, N2, during dry hole perforating; as a fracturing fluid during simultaneous perforating and fracturing; and in an impulse remedial treatment. A test of a tailored pulse explosive technique provided useful operational information but inadequate wellbore preparation compromised an assessment of its effectiveness to create a multiple fracture set. The application of these unconventional techniques provided a very useful and unique set of test data and proved to be sufficiently effective in permitting the engineers to acquire positive pressure interference data during a subsequent well test.

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