Method and System for Fracture Stimulation by Formation Displacement

Abstract

The present techniques provide methods and systems for fracturing reservoirs without directly treating them. For example, an embodiment provides a method for fracturing a subterranean formation. The method includes causing a volumetric increase in a zone proximate to the subterranean formation so as to apply a mechanical stress to the subterranean formation, creating a fracture network in the subterranean formation to improve permeability therein.

What is claimed is: 
     
         1 . A method for fracturing a subterranean formation, comprising applying stress in a zone proximate to the subterranean formation to indirectly translate a mechanical stress to the subterranean formation and effect a permeability increase within the subterranean formation. 
     
     
         2 . The method of  claim 1 , wherein the permeability increase is effected by creation of a fracture network in the subterranean formation. 
     
     
         3 . The method of  claim 1 , wherein the applied stress in the zone proximate affects a volumetric increase in the within the zone proximate. 
     
     
         4 . The method of  claim 1 , wherein the stress in the zone proximate causes at least a portion of the zone proximate to arch against at least a portion of the subterranean formation, producing a fracture network in the arched at least a portion of the subterranean formation. 
     
     
         5 . The method of  claim 1 , wherein the applied stress in the zone proximate produces a stress reduction in the in-situ stress of the zone proximate and enables the subterranean formation to arch toward at least a portion of the zone proximate, producing a fracture network in the arched at least a portion of the subterranean formation. 
     
     
         6 . The method of  claim 1 , wherein the effected permeability increase results from creation of a fracture network within an arched portion of the subterranean formation. 
     
     
         7 . The method of  claim 6 , wherein at least a portion of the fracture network results from delamination fracturing within the arched portion of the subterranean formation. 
     
     
         8 . The method of  claim 1 , wherein the zone proximate is below the subterranean formation, with respect to the wellbore path. 
     
     
         9 . The method of  claim 1 , applying the stress to a near-wellbore portion of the zone proximate to the subterranean formation to bend the subterranean formation and cause fractures to form in the subterranean formation. 
     
     
         10 . The method of  claim 1 , further comprising:
 thereafter reducing the applied stress to reversing at least a portion of the volumetric increase and effect rubblization within the subterranean formation; and   thereafter reapplying the applied stress to repeat the volumetric increase to cause further rubblization within the subterranean formation.   
     
     
         11 . The method of  claim 1 , wherein the subterranean formation comprises a hydrocarbon-bearing formation and the method further comprises extracting at least a portion of the hydrocarbons from the subterranean formation into a wellbore. 
     
     
         12 . The method of  claim 1 , wherein the zone proximate comprises an underburden formation layer. 
     
     
         13 . The method of  claim 1 , wherein creating the volumetric increase comprises pumping a fluid into the zone proximate. 
     
     
         14 . The method of  claim 13 , wherein the pumped fluid comprises a suspension of a proppant. 
     
     
         15 . The method of  claim 14 , wherein the proppant comprises waste product tailings. 
     
     
         16 . The method of  claim 1 , wherein applying the stress in the zone proximate comprises thermally expanding the zone proximate. 
     
     
         17 . The method of  claim 1 , wherein applying the stress to the zone proximate comprises expanding the zone proximate by a pressurized fluid without hydraulically fracturing the zone proximate. 
     
     
         18 . The method of  claim 1 , wherein applying the stress to the zone proximate comprises expanding a cavity or tunnel in the zone proximate by a pressurized fluid. 
     
     
         19 . The method of  claim 1 , wherein applying the stress to the zone proximate comprises expanding the zone proximate by a chemical reaction. 
     
     
         20 . The method of  claim 1 , wherein applying the stress to the zone proximate comprises expanding the zone proximate by a pressurized fluid. 
     
     
         21 . The method of  claim 1 , wherein applying the stress to the zone proximate comprises expanding the zone proximate with explosives. 
     
     
         22 . The method of  claim 1 , further comprising applying stress to the zone proximate so as to cause at least a portion of the subterranean formation to arch in a direction away from the zone proximate. 
     
     
         23 . The method of  claim 1 , further comprising applying stress to the zone proximate by reducing the in-situ geomechanical stress in the zone proximate so as to cause a volumetric reduction in at least a portion of the zone proximate and effect at least a portion of the subterranean formation to arch in a direction toward the zone proximate. 
     
     
         24 . A method for production of a hydrocarbon from a reservoir, comprising:
 penetrating a zone proximate a hydrocarbon bearing subterranean formation with a wellbore;   applying stress to the zone proximate to the subterranean formation to indirectly translate a mechanical stress change to the subterranean formation to arch at least a portion of the subterranean formation and thereby effect enhanced permeability within the arched portion of the subterranean formation; and   extracting hydrocarbons from the enhanced permeability subterranean formation into the wellbore.   
     
     
         25 . The method of  claim 24 , further comprising penetrating both the zone proximate and the hydrocarbon bearing subterranean formation with the wellbore. 
     
     
         26 . The method of  claim 24 , wherein the enhanced permeability results from creation of a fracture network within the arched portion of the subterranean formation. 
     
     
         27 . The method of  claim 26 , wherein at least a portion of the fracture network results from delamination fracturing within at least a portion of the arched portion of the subterranean formation. 
     
     
         28 . The method of  claim 24 , wherein the hydrocarbon bearing subterranean formation comprises a tight gas reservoir. 
     
     
         29 . The method of  claim 24 , wherein the hydrocarbon bearing subterranean formation comprises a shale gas reservoir. 
     
     
         30 . The method of  claim 24 , wherein the hydrocarbon bearing subterranean formation comprises a coal bed methane reservoir. 
     
     
         31 . The method of  claim 24 , wherein the hydrocarbon bearing subterranean formation comprises a tight oil reservoir. 
     
     
         32 . The method of  claim 30 , wherein a cleat system within the coal bed methane reservoir is opened to enhance conductivity. 
     
     
         33 . The method of  claim 24 , further comprising drilling a stimulation well to the zone proximate and applying the stress to the zone proximate from the stimulation well; and
 extracting the hydrocarbons from a wellbore other than the stimulation well.   
     
     
         34 . The method of  claim 33 , comprising drilling a production well from the stimulation well into the hydrocarbon bearing subterranean formation. 
     
     
         35 . The method of  claim 24 , further comprising applying stress to the zone proximate so as to cause at least a portion of the subterranean formation to arch in a direction away from the zone proximate. 
     
     
         36 . The method of  claim 24 , further comprising applying stress to the zone proximate by reducing the in-situ stress in the zone proximate so as to cause at least a portion of the subterranean formation to arch in a direction toward the zone proximate. 
     
     
         37 . The method of  claim 24 , further comprising drilling a production well into the hydrocarbon bearing subterranean formation after applying the stress to the zone proximate. 
     
     
         38 . The method of  claim 24 , further comprising drilling a production well into the hydrocarbon bearing subterranean formation before the step of applying the stress to the zone proximate is completed. 
     
     
         39 . The method of  claim 24 , further comprising cycling applying the stress and relieving the applies stress to cause a cycle of an expansion of the zone proximate and a contraction of the zone proximate to effect rubblizing a layer of material within the hydrocarbon bearing subterranean formation. 
     
     
         40 . The method of  claim 24 , further comprising:
 injecting waste product tailings into the zone proximate to prop open any fractures within the zone proximate.   
     
     
         41 . A hydrocarbon production system, comprising:
 a hydrocarbon bearing subterranean formation;   a zone proximate to the hydrocarbon bearing subterranean formation;   a stimulation well drilled to the zone proximate; and   a stimulation system configured to applying stress in the zone proximate to the subterranean formation to indirectly affect a mechanical stress to the hydrocarbon bearing subterranean formation and effect a volumetric increase within the hydrocarbon bearing subterranean formation.   
     
     
         42 . The hydrocarbon production system of  claim 41 , wherein the hydrocarbon bearing subterranean formation comprises a tight gas layer. 
     
     
         43 . The hydrocarbon production system of  claim 41 , wherein the hydrocarbon bearing subterranean formation comprises a shale gas layer. 
     
     
         44 . The hydrocarbon production system of  claim 41 , wherein the hydrocarbon bearing subterranean formation comprises a coal bed methane layer. 
     
     
         45 . The hydrocarbon production system of  claim 41 , wherein the hydrocarbon bearing subterranean formation comprises a tight oil layer. 
     
     
         46 . The hydrocarbon production system of  claim 41 , wherein the zone comprises a formation layer in an underburden. 
     
     
         47 . The hydrocarbon production system of  claim 41 , comprising a production well drilled into the hydrocarbon bearing subterranean formation. 
     
     
         48 . The hydrocarbon production system of  claim 41 , comprising a production well drilled into the hydrocarbon bearing subterranean formation from the stimulation well. 
     
     
         49 . The hydrocarbon production system of  claim 41 , further comprising applying stress to the zone proximate so as to cause at least a portion of the subterranean formation to arch in a direction away from the zone proximate. 
     
     
         50 . The hydrocarbon production system of  claim 41 , further comprising applying stress to the zone proximate by reducing the in-situ stress in the zone proximate so as to cause at least a portion of the subterranean formation to arch in a direction toward the zone proximate. 
     
     
         51 . A method for fracturing a subterranean formation, comprising causing a volumetric increase in a zone proximate to the subterranean formation so as to apply a mechanical stress to the subterranean formation.