Pressure Wave Tool For Unconventional Well Recovery

Abstract

A method is disclosed for selectively fracturing a formation in order to enhance recovery of hydrocarbons from unconventional reservoirs. The method includes generating a pressure wave having a frequency substantially in a resonant frequency range of a geological formation. The pressure wave is transmitted at a targeted location of the formation. A fluid may then be injected into the wellbore at a pressure that causes the fluid to enter any fractures resulting from the pressure wave.

What is claimed is: 
     
         1 . A method comprising:
 generating a pressure wave having a frequency substantially in a resonant frequency range of a geological formation;   directing the pressure wave at a targeted location of the formation; and   injecting a fluid into the wellbore at a pressure that causes the fluid to enter fractures resulting from the pressure wave.   
     
     
         2 . The method of  claim 1 , further comprising determining the resonant frequency range of the formation in response to a wireline operation. 
     
     
         3 . The method of  claim 1 , wherein injecting the fluid comprises injecting a gas into the wellbore. 
     
     
         4 . The method of  claim 1 , wherein injecting the fluid comprises injecting a fluid that adsorbs to kerogen. 
     
     
         5 . The method of  claim 1 , wherein injecting the fluid comprises injecting the fluid at or above a fracture gradient resulting from directing the pressure wave at the targeted location. 
     
     
         6 . The method of  claim 1 , wherein directing the pressure wave at the targeted location comprises directing the pressure wave from an active array antenna comprising a plurality of antenna elements. 
     
     
         7 . The method of  claim 6 , further comprising adjusting a phase and/or amplitude of a signal transmitted from the plurality of antenna elements to beamform the pressure wave to target the targeted location. 
     
     
         8 . The method of  claim 1 , wherein directing the pressure wave comprising directing the pressure wave from a pressure wave tool comprising a plurality of pressure wave generators. 
     
     
         9 . A tool apparatus comprising:
 a tool body configured to be lowered into a borehole of a geological formation; and   at least one pressure wave generator located on the tool body, the at least one pressure wave generator configured to transmit pressure waves at a resonant frequency of the geological formation.   
     
     
         10 . The tool apparatus of  claim 9 , wherein the at least one pressure wave generator comprises a plurality of antenna elements. 
     
     
         11 . The tool apparatus of  claim 10 , wherein the plurality of antenna elements comprise an active antenna array configured to produce a beamformed pressure wave. 
     
     
         12 . The tool apparatus of  claim 11 , further comprising a control circuit coupled to the plurality of antenna elements, the control circuit configured to control a phase and/or amplitude of a signal from each of the plurality of antenna elements to generate the beamformed pressure wave. 
     
     
         13 . The tool apparatus of  claim 12 , wherein the control circuit is further configured to avoid generating resonant frequencies of cement. 
     
     
         14 . The tool apparatus of  claim 9 , wherein the at least one pressure wave generator comprises a plurality of individual antenna elements located around the tool body. 
     
     
         15 . A system comprising:
 a rig to support a drillstring or a wireline tool;   a control circuit configured to execute beamforming; and   a pressure wave tool apparatus located in either the drillstring or the wireline tool and coupled to the control circuit, the apparatus comprising:
 a tool body; and 
 a plurality of pressure wave generators disposed around the tool body and configured to transmit a targeted pressure wave in response to the beamforming by the control circuit. 
   
     
     
         16 . The system of  claim 15 , wherein the control circuit is configured to control an amplitude and/or a phase of a signal transmitted from each antenna element such that the targeted pressure wave is at a frequency that avoids a resonant frequency of cement. 
     
     
         17 . The system of  claim 15 , wherein the plurality of pressure wave generators comprise a plurality of sound wave generators. 
     
     
         18 . The system of  claim 15 , wherein the plurality of pressure wave generators comprise a plurality of fluid wave generators. 
     
     
         19 . The system of  claim 18 , wherein the plurality of fluid wave generators are configured to vibrate a fluid at a frequency that is within a range of resonant frequencies of a formation. 
     
     
         20 . The system of  claim 15 , wherein a frequency of the targeted pressure wave is in a range of resonant frequencies of a target formation, wherein the range of resonant frequencies is determined based on wireline sonic logging tools or a microphone at a drill bit.