Real time maximum horizontal stress calibration based on predicted caliper log while drilling

Abstract

Systems and methods include a computer-method for updating drilling parameters in real time. A predicted breakout geometry is determined for a drilling operation of a petrochemical well. Determining the predicted breakout geometry uses an analytical elastic breakout model and includes determining a predicted breakout width, a predicted breakout depth, and a predicted breakout angle. The predicted breakout geometry is compared with an observed breakout geometry at an observed breakout angle determined in real time using real-time caliper log data obtained from a multi-finger caliper during the drilling operation. A maximum horizontal stress value in the analytical elastic breakout model is adjusted until the predicted breakout geometry matches the observed breakout geometry within a percentage threshold. Mud weight calculations for the drilling operation are updated in response to the comparing and adjusting. Drilling parameters for the drilling operation are changed in real time in response to the updating.

What is claimed is: 
     
         1 . A computer-implemented method, comprising:
 determining, using an analytical elastic breakout model, a predicted breakout geometry, including determining a predicted breakout width, a predicted breakout depth, and a predicted breakout angle for a drilling operation of a petrochemical well;   comparing the predicted breakout geometry with an observed breakout geometry at an observed breakout angle determined in real time using real-time caliper log data obtained from a multi-finger caliper during the drilling operation;   adjusting a maximum horizontal stress value in the analytical elastic breakout model until the predicted breakout geometry matches, within a percentage threshold, the observed breakout geometry;   updating, in response to the comparing and adjusting, mud weight calculations for the drilling operation; and   changing, in real time and in response to the updating, drilling parameters for the drilling operation.   
     
     
         2 . The computer-implemented method of  claim 1 , wherein determining the predicted breakout geometry is based on a pore pressure, a maximum horizontal stress azimuth, a tensile strength, a maximum horizontal stress (σ h ), a maximum vertical stress (σ V ), a cohesion friction angle UCS, and a Young Modulus Poisson’s ratio. 
     
     
         3 . The computer-implemented method of  claim 1 , wherein the analytical elastic breakout model uses geomechanical properties from a one-dimensional (1D) Mechanical Earth Model (MEM) and real-time data including an equivalent circulating density (ECD). 
     
     
         4 . The computer-implemented method of  claim 1 , wherein the analytical elastic breakout model supports computing effective stresses in combination with shear failure criteria. 
     
     
         5 . The computer-implemented method of  claim 4 , wherein computing the effective stresses includes computing various elastic solutions and poroelastic solutions. 
     
     
         6 . The computer-implemented method of  claim 4 , wherein the shear failure criteria include Mohr-Coulomb, Drucker-Prager, modified Lade, and Mogi-Coulomb techniques. 
     
     
         7 . The computer-implemented method of  claim 1 , wherein adjusting the maximum horizontal stress value in the analytical elastic breakout model includes incrementally adjusting the predicted breakout depth by 1%. 
     
     
         8 . A non-transitory, computer-readable medium storing one or more instructions executable by a computer system to perform operations comprising:
 determining, using an analytical elastic breakout model, a predicted breakout geometry, including determining a predicted breakout width, a predicted breakout depth, and a predicted breakout angle for a drilling operation of a petrochemical well;   comparing the predicted breakout geometry with an observed breakout geometry at an observed breakout angle determined in real time using real-time caliper log data obtained from a multi-finger caliper during the drilling operation;   adjusting a maximum horizontal stress value in the analytical elastic breakout model until the predicted breakout geometry matches, within a percentage threshold, the observed breakout geometry;   updating, in response to the comparing and adjusting, mud weight calculations for the drilling operation; and   changing, in real time and in response to the updating, drilling parameters for the drilling operation.   
     
     
         9 . The non-transitory, computer-readable medium of  claim 8 , wherein determining the predicted breakout geometry is based on a pore pressure, a maximum horizontal stress azimuth, a tensile strength, a maximum horizontal stress (σ h ), a maximum vertical stress (σ V ), a cohesion friction angle UCS, and a Young Modulus Poisson’s ratio. 
     
     
         10 . The non-transitory, computer-readable medium of  claim 8 , wherein the analytical elastic breakout model uses geomechanical properties from a one-dimensional (1D) Mechanical Earth Model (MEM) and real-time data including an equivalent circulating density (ECD). 
     
     
         11 . The non-transitory, computer-readable medium of  claim 8 , wherein the analytical elastic breakout model supports computing effective stresses in combination with shear failure criteria. 
     
     
         12 . The non-transitory, computer-readable medium of  claim 11 , wherein computing the effective stresses includes computing various elastic solutions and poroelastic solutions. 
     
     
         13 . The non-transitory, computer-readable medium of  claim 11 , wherein the shear failure criteria include Mohr-Coulomb, Drucker-Prager, modified Lade, and Mogi-Coulomb techniques. 
     
     
         14 . The non-transitory, computer-readable medium of  claim 8 , wherein adjusting the maximum horizontal stress value in the analytical elastic breakout model includes incrementally adjusting the predicted breakout depth by 1%. 
     
     
         15 . A computer-implemented system, comprising:
 one or more processors; and   a non-transitory computer-readable storage medium coupled to the one or more processors and storing programming instructions for execution by the one or more processors, the programming instructions instructing the one or more processors to perform operations comprising:
 determining, using an analytical elastic breakout model, a predicted breakout geometry, including determining a predicted breakout width, a predicted breakout depth, and a predicted breakout angle for a drilling operation of a petrochemical well; 
 comparing the predicted breakout geometry with an observed breakout geometry at an observed breakout angle determined in real time using real-time caliper log data obtained from a multi-finger caliper during the drilling operation; 
 adjusting a maximum horizontal stress value in the analytical elastic breakout model until the predicted breakout geometry matches, within a percentage threshold, the observed breakout geometry; 
 updating, in response to the comparing and adjusting, mud weight calculations for the drilling operation; and 
 changing, in real time and in response to the updating, drilling parameters for the drilling operation. 
   
     
     
         16 . The computer-implemented system of  claim 15 , wherein determining the predicted breakout geometry is based on a pore pressure, a maximum horizontal stress azimuth, a tensile strength, a maximum horizontal stress (σ h ), a maximum vertical stress (σ V ), a cohesion friction angle UCS, and a Young Modulus Poisson’s ratio. 
     
     
         17 . The computer-implemented system of  claim 15 , wherein the analytical elastic breakout model uses geomechanical properties from a one-dimensional (1D) Mechanical Earth Model (MEM) and real-time data including an equivalent circulating density (ECD). 
     
     
         18 . The computer-implemented system of  claim 15 , wherein the analytical elastic breakout model supports computing effective stresses in combination with shear failure criteria. 
     
     
         19 . The computer-implemented system of  claim 18 , wherein computing the effective stresses includes computing various elastic solutions and poroelastic solutions. 
     
     
         20 . The computer-implemented system of  claim 18 , wherein the shear failure criteria include Mohr-Coulomb, Drucker-Prager, modified Lade, and Mogi-Coulomb techniques.