Method of treating subterranean reservoirs

Abstract

A method of fracturing a rock formation is provided including placing through a wellbore penetrating the rock formation propellants in a cavity located at a radial distance from the wellbore and igniting the propellants to cause a pressure sufficient to fracture the formation.

1 . A method of fracturing a rock formation, comprising:
 a) through a wellbore penetrating said rock formation placing propellants entirely in a cavity located at a radial distance from said wellbore; and   b) igniting said propellants to cause a pressure sufficient to fracture said formation, whereby the propellants are not within the wellbore when ignited.   
   
   
       2 . A method in accordance with  claim 1 , wherein the rock formation includes carbonate rock being hydrocarbon bearing. 
   
   
       3 . A method in accordance with  claim 1 , wherein the propellant has a pressure rise time of 0.4 ms or more. 
   
   
       4 . A method in accordance with  claim 1 , wherein the wellbore is designed to be accessible from the surface by logging tools. 
   
   
       5 . A method in accordance with  claim 1 , wherein the cavity is a perforation. 
   
   
       6 . A method in accordance with  claim 1 , wherein the cavity is a fracture. 
   
   
       7 . A method in accordance with  claim 1 , wherein the cavity is a microborehole. 
   
   
       8 . A method in accordance with  claim 7 , wherein the microborehole has a diameter of 13 cm (4′) or less. 
   
   
       9 . A method in accordance with  claim 7 , wherein the microborehole has a diameter of 7 cm (2′) or less. 
   
   
       10 . A method in accordance with  claim 1 , wherein the propellant is ignited using a signal from the surface. 
   
   
       11 . A method in accordance with  claim 1 , wherein the propellant is ignited using delayed ignition energy release mechanism co-placed with said propellant. 
   
   
       12 . A method in accordance with  claim 1 , wherein the propellant is characterized by a state selected from the group consisting of solid, geleous or liquid. 
   
   
       13 . A method in accordance with  claim 1 , wherein igniting the propellants is designed to generate further cavities in the formation for iterative placements of further propellants. 
   
   
       14 . A method of producing hydrocarbon fluids from a rock formation having a network of fractures, comprising the steps of guiding a heated fluid into the formation through said network of fractures, letting the heated fluid increase the mobility of the hydrocarbon fluids, and moving the hydrocarbon fluids to the surface, wherein said network of fractures is made accessible by placing through a wellbore penetrating said rock formation propellants entirely in a cavity located at a radial distance from said wellbore; and igniting said propellants to cause a pressure sufficient to fracture said formation, thereby creating increased access to said network of fractures, and whereby the propellants are not within the wellbore when ignited.