Hydraulic Fracturing Process for Deviated Wellbores

Abstract

A method of stimulating an interval in a hydrocarbon reservoir equipped with a deviated wellbore having a casing, wherein said interval comprises at least two sequential stages in said wellbore without isolation means, said method comprising: i) introducing a first stage ii) introducing a second stage in the same wellbore wherein said first stage, and second stage are not separated by any isolation means; and optionally iii) recovering hydrocarbon from said hydrocarbon reservoir to a surface.

1 . A method of stimulating an interval in a hydrocarbon reservoir equipped with a deviated wellbore having a casing, wherein said interval comprises at least two sequential stages in said wellbore without isolation means, said method comprising:
 i) introducing a first stage by:
 a) creating at least one access point through said wellbore casing into a hydrocarbon reservoir; 
 b) introducing at least one fracturing fluid to said aforementioned access point to stimulate hydrocarbon production from said hydrocarbon reservoir; 
   ii) introducing a second stage in the same wellbore by:
 a) creating a second access point through said wellbore casing, proximate said first stage, into a hydrocarbon reservoir; 
   b) introducing at least one fracturing fluid to said second access point to stimulate hydrocarbon production from said hydrocarbon reservoir;   wherein said first stage, and second stage are not separated by any isolation means; and optionally   iii) recovering hydrocarbon from said hydrocarbon reservoir to a surface.   
     
     
         2 . The method of  claim 1  wherein the access point through the wellbore casing comprises at least one perforation. 
     
     
         3 . The method of  claim 2  wherein said at least one perforation is substantially perpendicular to the wellbore casing. 
     
     
         4 . The method of  claim 3  wherein said access point comprises several perforations. 
     
     
         5 . The method of  claim 3  or  4  wherein the perforations are positioned on the wellbore casing selected from: substantially one line along said wellbore casing, or substantially around said wellbore casing. 
     
     
         6 . The method of  claim 1  wherein the at least one fracturing fluid is selected from the group consisting of liquids, gases and a combination thereof. 
     
     
         7 . The method of  claim 6  wherein said fracturing fluid further comprises at least one solid. 
     
     
         8 . The method of  claim 1  wherein the recovery of hydrocarbon further comprises the steps of: ceasing the introduction of the at least one fracturing fluid; reduction of pressure at the wellbore and recovering the hydrocarbon through the wellbore to the surface. 
     
     
         9 . The method of  claim 1  wherein the new interval comprises at least three stages not separated by any isolation means. 
     
     
         10 . A method of stimulating a hydrocarbon reservoir by stimulating at least two intervals according to the method of  claim 9 , wherein said at least two intervals are separated by isolation means. 
     
     
         11 . A method of stimulating a new interval in a hydrocarbon reservoir equipped with a deviated wellbore and casing by introducing at least two sequential stages into said wellbore without requiring any isolation means, said method comprising:
 i) introducing a first stage having a predetermined length by:
 a) creating at least one access point through said wellbore casing into a hydrocarbon reservoir; 
 b) introducing at least one fracturing fluid to said at least one access point to stimulate hydrocarbon production from said hydrocarbon reservoir; 
 c) monitoring the fracturing pressure in the wellbore; 
   ii) introducing a second stage having a predetermined length in the same well by:
 a) creating a second access point through said wellbore casing into a hydrocarbon reservoir proximate the first stage; 
 b) introducing at least one fracturing fluid to said second access point to stimulate hydrocarbon production from said hydrocarbon reservoir; 
   wherein said first stage, and second stage are not separated by any isolation means;   iii) recovering hydrocarbon from said hydrocarbon reservoir.   
     
     
         12 . The method of  claim 11  wherein each access point comprises at least one perforation. 
     
     
         13 . The method of  claim 12  wherein each access point comprises a plurality of perforations proximate each other. 
     
     
         14 . The method of  claim 13  wherein each perforation is at a distance of less than one meter from each other in the same stage. 
     
     
         15 . A method of fracturing multiple stages in hydrocarbon deposits for horizontal wellbore intervals without using isolation means, said method comprising the steps of:
 a) selecting a wellbore appropriate for carrying out the method of fracturing without the use of isolation means;   b) selecting an appropriate stage location in said wellbore;   c) perforating at least one perforation, preferably a set of perforations at a first opening for the first stage of the wellbore;   d) pumping at least one stimulation fluid or sequence of stimulation fluids into said at least one perforation;   e) observing the injection rates, and pressure in the stage selected;   f) selecting an appropriate stage location in said wellbore;   g) perforating at least one perforation, preferably a set of perforations at a consecutive opening for the consecutive stage of the wellbore without use of isolation means;   h) pumping at least one stimulation fluid or sequence of stimulation fluids into said at least one perforation;   i) observing the injection rates, and pressure in the stages;   j) optionally repeating steps (f) to (i) without isolation means between the stages.   
     
     
         16 . The method of  claim 15  wherein the at least one stimulation fluid further comprises radioactive material to determine effectiveness of fracturing steps in said perforations. 
     
     
         17 . A process of hydraulic fracturing multiple hydrocarbon deposits in horizontal wellbore intervals comprising fracturing of at least two stages according to  claim 15 . 
     
     
         18 . A method of hydraulic fracturing a horizontal wellbore as per  claim 15  wherein at least two stages of the well subsequent to the first stage are fractured without using conventional diverting techniques and the location of the subsequent stages are selected by observing the injection rates, fluid path and pressure differences in the stage selected by optionally charting micro-seismic and radioactive indications in said deposit. 
     
     
         19 . A method of stimulating a new interval, in a substantially horizontal wellbore, in a hydrocarbon reservoir, said method comprises introducing two or more sequential stages into said wellbore without isolation means between said stages, said method comprising:
 i) introducing a first stage by:
 a) creating a first access point through a wellbore casing into a hydrocarbon formation; 
 b) introducing at least one fracturing fluid to said first access point at a sufficient rate, to stimulate hydrocarbon production from said hydrocarbon formation; 
 c) monitoring operating conditions of said wellbore at a predetermined time throughout said method; 
   ii) introducing a second stage in the same wellbore by:
 a) creating a second access point, proximate said first stage, through a wellbore casing into a hydrocarbon formation; 
 b) introducing at least one fracturing fluid to said second access point at a sufficient rate, to stimulate hydrocarbon production from said hydrocarbon formation; 
 c) monitoring operating conditions of said wellbore at a predetermined time throughout said method; 
   iii) introducing a consecutive stage (or stages) in the same wellbore by:
 a) creating at least one consecutive access point through a wellbore casing into a hydrocarbon formation proximate a previous stage; 
 b) introducing at least one fracturing fluid to said consecutive access point at a sufficient rate, to stimulate hydrocarbon production from said hydrocarbon formation; 
 c) monitoring operating conditions of the wellbore at a predetermined time throughout said method; 
 d) terminating stimulation to allow for recovery of hydrocarbons; and 
 e) recovering hydrocarbons from said hydrocarbon reservoir; 
   
       wherein said two or more sequential stages are not separated by any isolation means. 
     
     
         20 . An interval in a hydrocarbon reservoir equipped with a deviated wellbore, said interval comprising at least two sequential stages not isolated by any isolation means.