Method and System for Fracturing a Formation

Abstract

Systems and methods are described for fracturing a production formation. A method includes drilling a well into a zone proximate to a production formation, and increasing a volume of the zone through the well in order to apply a mechanical stress to the production formation.

What is claimed is: 
     
         1 . A method for fracturing a production formation, comprising:
 drilling a well into a zone proximate to a production formation; and   increasing a volume of the zone through the well in order to apply a mechanical stress to the production formation.   
     
     
         2 . The method of  claim 1 , wherein the mechanical stress is applied to only a portion of the production formation so as to create a bending motion in the production formation and cause fractures to form through delamination. 
     
     
         3 . The method of  claim 1 , comprising:
 isolating a portion of the well that accesses the zone from a portion of the well that accesses the production formation;   completing a portion of the well in the production formation; and   producing hydrocarbons through the well.   
     
     
         4 . The method of  claim 1 , further comprising:
 reversing the volume change; and   repeating the volume change for one or more cycles to cause rubblization along a delamination fracture in the production formation.   
     
     
         5 . The method of  claim 1 , comprising:
 drilling a first horizontal branch from the well into the zone below the production formation;   drilling a second horizontal branch from the well into the production formation;   changing the volume of the zone using the first horizontal branch; and   producing hydrocarbons from the production formation using the second horizontal branch.   
     
     
         6 . The method of  claim 1 , comprising:
 drilling a horizontal branch from the well into the zone; and   changing the volume of the zone at a plurality of points along the horizontal branch.   
     
     
         7 . The method of  claim 1 , comprising:
 drilling a horizontal branch from the well into the production formation;   drilling a plurality of vertical branches into the zone from the horizontal branch; and   changing the volume of the zone at a point along the vertical branch.   
     
     
         8 . The method of  claim 1 , comprising:
 creating a notch in the production formation; and   fracturing the production formation at the notch to create a horizontal fracture.   
     
     
         9 . The method of  claim 1 , comprising:
 creating a notch in the zone; and   fracturing the zone at the notch to create a horizontal fracture.   
     
     
         10 . The method of  claim 1 , comprising monitoring a change in volume of the zone. 
     
     
         11 . The method of  claim 10 , comprising creating a microseismic map of the zone. 
     
     
         12 . The method of  claim 10 , comprising tracking changes in angle at a ground surface or in an existing wellbore. 
     
     
         13 . The method of  claim 1 , wherein changing the volume comprises expanding the zone by injecting a pressurized fluid without fracturing the zone. 
     
     
         14 . The method of  claim 1 , further comprising producing a hydrocarbon from the production formation. 
     
     
         15 . A hydrocarbon production system, comprising:
 a hydrocarbon reservoir;   a zone proximate to the hydrocarbon reservoir;   a stimulation well drilled to the zone;   a stimulation system configured to create a volumetric change in the zone through the stimulation well; and   a production well drilled to the hydrocarbon reservoir.   
     
     
         16 . The hydrocarbon production system of  claim 15 , wherein the stimulation well comprises a horizontal segment through the zone and openings at a plurality of locations along the horizontal segment are used to create the volumetric change. 
     
     
         17 . The hydrocarbon production system of  claim 15 , wherein the hydrocarbon reservoir comprises a tight gas layer. 
     
     
         18 . The hydrocarbon production system of  claim 15 , wherein the hydrocarbon reservoir comprises a shale rock, a mudstone rock, a sandstone, or any combinations thereof. 
     
     
         19 . The hydrocarbon production system of  claim 15 , comprising a vertical well that is drilled to both the hydrocarbon reservoir and the zone, wherein:
 an opening into the zone is used for the volumetric change; and   an opening into the hydrocarbon reservoir is used for production.   
     
     
         20 . The hydrocarbon production system of  claim 15 , wherein:
 the stimulation well is a first horizontal branch from a vertical well; and   the production well is a second horizontal branch from a vertical well.   
     
     
         21 . The hydrocarbon production system of  claim 20 , wherein openings at a plurality of locations along the first horizontal branch are used to create the volumetric change at each opening. 
     
     
         22 . The hydrocarbon production system of  claim 15 , wherein:
 the production well comprises a horizontal branch through the production formation; and   the stimulation well comprises a plurality of vertical branches off of the horizontal branch that reach into the zone.   
     
     
         23 . The hydrocarbon production system of  claim 15 , wherein:
 the stimulation well comprises a plurality of horizontal branches in the zone; and   a plurality of openings along each of the plurality of horizontal branches are used to create a volumetric change at each of the plurality of openings.   
     
     
         24 . The hydrocarbon production system of  claim 23 , wherein the plurality of horizontal branches are arranged in a dual lateral, quadrilateral, multilateral, or pinnate formation. 
     
     
         25 . The hydrocarbon production system of  claim 15 , wherein:
 the production well comprises a plurality of horizontal branches in the production formation; and   the stimulation well comprises a plurality of vertical branches along each of the plurality of horizontal branches, wherein an opening along each of the plurality of vertical branches is used to create a volumetric change at the opening.   
     
     
         26 . The hydrocarbon production system of  claim 25 , wherein the plurality of horizontal branches are arranged in a dual lateral, quadrilateral, multilateral, or pinnate formation. 
     
     
         27 . A method for harvesting hydrocarbons from a formation, comprising:
 drilling a production well in a production interval;   drilling a stimulation well in a treatment interval;   causing a volumetric change in the treatment interval through the stimulation well, wherein the volumetric change causes the formation of a fracture field in the production interval;   completing the production well to place the production well in contact with the fracture field; and   harvesting hydrocarbons from the production interval.   
     
     
         28 . The method of  claim 27 , comprising:
 forming a notch in the rock of the production interval from an opening in the production well; and   fracturing the rock of the production interval through the notch to create a horizontal fracture to the fracture field.   
     
     
         29 . The method of  claim 27 , comprising:
 forming a notch in the rock of the treatment interval from an opening in the stimulation well; and   fracturing the rock of the treatment interval through the notch to create a horizontal fracture; and   causing a volumetric increase in the treatment interval by pumping a fluid into the horizontal fracture in the rock of the treatment interval.