In situ fluid reservoir stimulation process

Abstract

Methods and processes for in-situ stimulation of hydrocarbon containing formations using energy to expand in-situ liquid hydrocarbons, thus rejuvenating naturally occurring fractures. In some embodiments, the energy is supplied as heat from injection of an oxygen containing fluid.

1 . A method for stimulating a hydrocarbon containing formation, comprising:
 introducing a heat source in the formation;   heating a portion of liquid hydrocarbons in the formation to expand their volume, thereby rejuvenating fractures in the formation;   passing at least some of the heated liquid hydrocarbons through the rejuvenated fractures; and   producing at least a portion of the liquid hydrocarbons that passed through the rejuvenated fractures.   
     
     
         2 . The method of  claim 1 , wherein a portion of the rejuvenated fractures originally occurred naturally. 
     
     
         3 . The method of  claim 1 , further comprising heating a portion of gaseous hydrocarbons in the formation to expand their volume, thereby assisting in rejuvenating the formation fractures. 
     
     
         4 . The method of  claim 1 , wherein the formation comprises shale. 
     
     
         5 . The method of  claim 4 , wherein the shale has a vitrinite reflectance of between about 0.5% and about 1.1%. 
     
     
         6 . The method of  claim 4 , wherein the shale has a vitrinite reflectance of between about 0.6% and about 1.0%. 
     
     
         7 . The method of  claim 4 , wherein the shale has a vitrinite reflectance of between about 0.7% and about 0.9%. 
     
     
         8 . The method of  claim 1 , wherein the heat source comprises a reactant that will react in situ exothermically. 
     
     
         9 . The method of  claim 1 , wherein the heat source comprises an oxygen containing fluid. 
     
     
         10 . The method of  claim 9 , wherein the oxygen containing fluid is delivered from the surface at a pressure of at least about 4,000 psi and a temperature of at least about 120 degrees Fahrenheit. 
     
     
         11 . The method of  claim 1 , wherein the heat source comprises a heater. 
     
     
         12 . The method of  claim 1 , wherein the step of introducing a heat source heat source comprises introducing an oxygen containing fluid into an access wellbore and auto-igniting the oxygen containing fluid with in situ hydrocarbons. 
     
     
         13 . The method of  claim 1 , wherein the steps of heating a portion of liquid hydrocarbons and passing at least some of the heated liquid hydrocarbons through the rejuvenated fractures occurs at a pressure above the bubble point pressure of the liquid hydrocarbons. 
     
     
         14 . The method of  claim 1 , further comprising providing at least one access wellbore and at least one production wellbore. 
     
     
         15 . The method of  claim 1 , further comprising thermally expanding in situ water. 
     
     
         16 . The method of  claim 1 , further comprising generating steam in situ. 
     
     
         17 . The method of  claim 1 , further comprising expanding at least a portion of the liquid hydrocarbons via gas solubilization. 
     
     
         18 . The method of  claim 1 , further comprising desorbing liquid hydrocarbons from in situ kerogen. 
     
     
         19 . The method of  claim 1 , further comprising pyrolysis of in situ kerogen. 
     
     
         20 . The method of  claim 1 , wherein the heat source comprises an oxygen containing fluid that creates an in situ combustion reaction; and further comprising perpetuating throughout a portion of the formation the steps of heating a portion of liquid hydrocarbons and passing at least some of the heated liquid hydrocarbons through the rejuvenated fractures by mechanisms selected from the group consisting of:
 thermal conduction of heat through the formation,   heat conduction from the migrating heated hydrocarbons,   heat convection from the migrating heated hydrocarbons,   combustion front advancement as combustible hydrocarbons are depleted with continued oxygen containing gas injection, and any combination thereof.