Creating multiple fractures in a subterranean formation

Claim 1

A METHOD OF FRACTURING A WELL PENETRATING A FLUIDBEARING SUBTERRANEAN FORMATION COMPRISING THE STEPS OF: (1) INJECTING A FRACTURING LIQUID CONTAINING A PROPPING AGENT DISPERSED THEREIN DOWN THE WELLBORE OF THE WELL AND BACK INTO THE FORMATION UNTIL AT LEAST ONE FRACTURE IS CREATED THEREIN; (2) INCORPORATING INTO THE FRACTURING LIQUID CONTAINING THE PROPPING AGENT A GAS, WHICH IS SUBSTANTIALLY UNREACTIVE WITH THE LIQUID AND WITH THE FORMATION FLUIDS, IN AN AMOUNT SUFFICIENT TO PROVIDE AN UNDISSOLVED FREE GAS PHASE AS BUBBLES WITHIN THE LIQUID PHASE, HAVING A FREE GAS TO LIQUID VOLUME RATIO OF MORE THAN ABOUT 0.2 AT THE PRESSURE AND TEMPERATURE CONDITIONS EXISTING AT THE DEPTH OF THE FORMATION BEING FRACTURED AND CONTINUING TO INJECT THE TWOPHASE FLUID MIXTURE, WITHOUT SUBSTANTIAL INCREASE IN THE RATE OF INJECTION TO PLUG AT LEAST PARTIALLY THE FRACTURES CREATED IN STEP (1); (3) SUBSTANTIALLY REPEATING (1) BY DECREASING THE AMOUNT OF GAS INCORPORATED IN THE FRACTURING LIQUID TO THAT WHICH WILL CONTINUE TO PROVIDE A GAS-LIQUID VOLUME RATIO, WHEN THE PRESSURE TIS REDUCED, TO ONLY THAT RESULTING FROM THE HYDROSTATIC HEAD BUT WHICH IS LESS THAN ABOUT 0.2 AT THE PRESSURE AND TEMPERATURE CONDITIONS EXISTING AT THE DEPTH OF THE FORMATION BEING FRACTURED, AND CONTINUING TO INJECT THE FRACTURING LIQUID, WITHOUT SUBSTANTIAL DECREASE IN THE RATE OF INJECTION, THEREBY TO PROVIDE BRANCHED, MULTIPLE, CONNECTING ADVENTITIOUS-TYPE FRACTURES EMANATING OUTWARDLY FROM THE EARLIER FORMED FRACTURES.

Claim 2

A METHOD OF FRACTURING A WELL PENETRATING A FLUIDBEARING SUBTERRANEAN FORMATION COMPRISING THE STEPS OF: (1) INJECTING A FRACTURING LIQUID CONTAINING A PROPPING AGENT DISPERSED THEREIN DOWN THE WELLBORE OF THE WELL AND BACK INTO THE FORMATION UNTIL AT LEAST ONE FRACTURE IS CREATED THEREIN; (2) INCORPORATING INTO THE FRACTURING LIQUID CONTAINING THE PROPPING AGENT A GAS, WHICH IS SUBSTANTIALLY UNREACTIVE WITH THE LIQUID AND WITH THE FORMATION FLUIDS, IN AN AMOUNT SUFFICIENT TO PROVIDE AN UNDISSOLVED FREE GAS PHASE AS BUBBLES WITHIN THE LIQUID PHASE, HAVING A FREE GAS TO LIQUID VOLUME RATIO OF MORE THAN ABOUT 0.2 AT THE PRESSURE AND TEMPERATURE CONDITIONS EXISTING AT THE DEPTH OF THE FORMATION BEING FRACTURED AND CONTINUING TO INJECT THE TWOPHASE FLUID MIXTURE, WITHOUT SUBSTANTIAL INCREASE IN THE RATE OF INJECTION TO PLUG AT LEAST PARTIALLY THE FRACTURES CREATED IN STEP (1); (3) SUBSTANTIALLY REPEATING (1) BY DECREASING THE AMOUNT OF GAS INCORPORATED IN THE FRACTURING LIQUID TO THAT WHICH WILL CONTINUE TO PROVIDE A GAS-LIQUID VOLUME RATIO, WHEN THE PRESSURE TIS REDUCED, TO ONLY THAT RESULTING FROM THE HYDROSTATIC HEAD BUT WHICH IS LESS THAN ABOUT 0.2 AT THE PRESSURE AND TEMPERATURE CONDITIONS EXISTING AT THE DEPTH OF THE FORMATION BEING FRACTURED, AND CONTINUING TO INJECT THE FRACTURING LIQUID, WITHOUT SUBSTANTIAL DECREASE IN THE RATE OF INJECTION, THEREBY TO PROVIDE BRANCHED, MULTIPLE, CONNECTING ADVENTITIOUS-TYPE FRACTURES EMANATING OUTWARDLY FROM THE EARLIER FORMED FRACTURES.