US Patent 7559373 Process for fracturing a subterranean formation

A well may intersect a mineral bearing stratum. A fracturing fluid in the nature of a non-participating gas may be injected into the stratum at high rates of flow, to yield a high down hole pressure, and a time v. pressure pulse extending over a period of time. A second pulse may follow the first pulse in relatively quick succession. There may be pauses, or period of relative relaxation between the pulses.