System and method for determining sidetrack zones

Abstract

A method of identifying sidetrack zones in an underground wellbore includes receiving hole-casing data, and determining one or more candidate sidetrack zones based on identifying cement overlap areas from the hole-casing data. The method further includes receiving completion data for one or more completion elements and determining a completion depth for each of the one or more completion elements based on the completion data. The method further includes selecting one or more sidetrack zones by filtering the one or more candidate sidetrack zones based on one or more of the completion depths.

What is claimed is: 
     
         1 . A method of identifying sidetrack zones in an underground wellbore, comprising:
 receiving hole-casing data;   determining one or more candidate sidetrack zones based on identifying cement overlap areas from the hole-casing data;   receiving completion data for one or more completion elements;   determining a completion depth for each of the one or more completion elements based on the completion data; and   selecting one or more sidetrack zones by filtering the one or more candidate sidetrack zones based on one or more of the completion depths.   
     
     
         2 . The method of  claim 1 , further including receiving cementing data and wherein filtering includes filtering the one or more candidate sidetrack zones based on the cementing data. 
     
     
         3 . The method of  claim 2 , further including identifying, based on the cementing data, a cement quality for one or more areas of the wellbore and wherein filtering includes filtering out one or more candidate sidetrack zones not associated with areas of good cement quality. 
     
     
         4 . The method of  claim 1 , wherein the one or more completion elements include a production packer. 
     
     
         5 . The method of  claim 4 , wherein filtering includes filtering out one or more candidate sidetrack zones below the completion depth of the production packer. 
     
     
         6 . The method of  claim 1 , wherein the one or more candidate sidetrack zones are defined by one or more areas of a single layer of casing cemented to the wellbore. 
     
     
         7 . The method of  claim 1 , wherein determining the one or more candidate sidetrack zones further includes reducing one or more of the candidate sidetrack zones based on an associated casing having a casing depth above a shallow casing threshold. 
     
     
         8 . The method of  claim 7 , wherein reducing includes reducing a length of the candidate sidetrack zone to a single point. 
     
     
         9 . The method of  claim 8 , wherein the single point is a lowest point in the candidate sidetrack zone. 
     
     
         10 . The method of  claim 1 , further including performing the method for a plurality of underground wellbores in parallel. 
     
     
         11 . The method of  claim 1 , further including performing the method for at least 50 underground wellbores in parallel. 
     
     
         12 . The method of  claim 1 , further including performing the method in under 1 minute. 
     
     
         13 . The method of  claim 1 , further including performing the method for a plurality of underground wellbores in parallel in under 1 minute. 
     
     
         14 . The method of  claim 1 , further including performing the method automatically and without user input. 
     
     
         15 . The method of  claim 1 , further including receiving target data, and wherein filtering includes filtering the one or more candidate sidetrack zones based on the target data. 
     
     
         16 . The method of  claim 15 , wherein filtering the one or more candidate sidetrack zones based on the target data includes determining, based on the target data, one or more sidetrack trajectories to reach a target through one or more of the candidate sidetrack zones. 
     
     
         17 . The method of  claim 16 , further including selecting a sidetrack trajectory of the one or more sidetrack trajectories based on a cost function for accessing the target. 
     
     
         18 . The method of  claim 17 , further comprising causing the selected sidetrack trajectory to be implemented in a downhole drilling operation. 
     
     
         19 . A system, comprising:
 one or more processors:   a memory in electronic communication with the one or more processors; and   instructions stored in the memory, the instructions being executable by the one or more processors to:
 receive hole-casing data; 
 determine one or more candidate sidetrack zones based on identifying areas of casing overlap from the hole-casing data; 
 receive completion data for one or more completion elements; 
 determine a completion depth for each of the one or more completion elements based on the completion data; and 
 select one or more sidetrack zones by filtering the one or more candidate sidetrack zones based on one or more of the completion depths. 
   
     
     
         20 . A computer-readable storage medium including instructions that, when executed by at least one processor, cause the processor to:
 receive hole-casing data;   determine one or more candidate sidetrack zones based on identifying areas of casing overlap from the hole-casing data;   receive completion data for one or more completion elements;   determine a completion depth for each of the one or more completion elements based on the completion data; and   select one or more sidetrack zones by filtering the one or more candidate sidetrack zones based on one or more of the completion depths.