Automated geosteering based on a distance to oil-water contact

1. A method for performing automated geosteering, the method comprising:

receiving, by a processing system, first formation evaluation data from a bottom hole assembly disposed in a wellbore at a first data point and second formation evaluation data from the bottom hole assembly disposed in the wellbore at a second data point;

determining, by the processing system, a first position data of a formation boundary from the first formation evaluation data at the first data point and a second position data of the formation boundary from the second formation evaluation data at the second data point;

determining a first sphere from the first data point and the first position data;

determining a second sphere from the second data point and the second position data;

determining a location point of the formation boundary on a section of the first sphere that is not included in the second sphere;

extrapolating, by the processing system, the location point to generate extrapolated position data of the formation boundary; and

maintaining a distance between the bottom hole assembly and the formation boundary by adjusting a trajectory of the wellbore, the adjusting comprising transmitting steering commands to a steering tool to steer the bottom hole assembly, the adjusting based at least in part on the extrapolated position data of the formation boundary.

2. The method of claim 1 , wherein the extrapolated position data is determined with a polynomial.

3. The method of claim 2 , wherein the extrapolated position data is determined based on measured depth.

4. The method of claim 1 , wherein the extrapolated position data of the formation boundary is along a planned trajectory of the wellbore.

5. The method of claim 1 , wherein the extrapolated position data of the formation boundary is determined at least partially based on directional data.

6. The method of claim 5 , wherein the directional data is at least one of an inclination of a portion of the bottom hole assembly, an azimuth of the portion of the bottom hole assembly, or a toolface angle of a direction in which the formation boundary is located.

7. The method of claim 1 , wherein the trajectory is adjusted at least partially based on a predefined threshold of a distance between the adjusted trajectory and the formation boundary.

8. The method of claim 1 , further comprising:

filtering, by the processing system, at least one of the first formation evaluation data or the second formation evaluation data to generate filtered formation evaluation data; and

determining, by the processing system, the location point of the formation boundary from the filtered formation evaluation data.

9. The method of claim 1 , wherein adjusting the trajectory comprises adjusting a setpoint for a control process to steer the bottom hole assembly.

10. The method of claim 1 , wherein at least one of the first distance or the second distance is at least one of a distance from the bottom hole assembly to the formation boundary, or a true vertical depth of the formation boundary.

11. A system for performing automated geosteering of a wellbore, the system comprising:

a bottom hole assembly disposed in the wellbore; and

a processing system for executing computer readable instructions, the computer readable instructions controlling the processing system to perform operations comprising:

receiving, by the processing system, first formation evaluation data from the bottom hole assembly disposed in the wellbore at a first data point and second formation evaluation data from the bottom hole assembly disposed in the wellbore at a second data point;

determining, by the processing system, a first postion data of a formation boundary from the formation evaluation data at the first data point and a second position data of the formation boundary from the formation evaluation data at the second data point;

determining a first sphere from the first data point and the first position data;

determining a second sphere from the second data point and the second positon data;

determining a location point of the formation boundary on a section of the first sphere that is not included in the second sphere;

extrapolating, by the processing system, the location point to generate extrapolated position data of the formation boundary; and

maintaining a distance between the bottom hole assembly and the formation boundary by adjusting a trajectory of the wellbore, the adjusting comprising transmitting steering commands to a steering tool to steer the bottom hole assembly, the adjusting based at least in part on the extrapolated position data of the formation boundary.

12. The system of claim 11 , wherein the extrapolated position data is determined with a polynomial.

13. The system of claim 12 , wherein the extrapolated position data is determined based on measured depth.

14. The system of claim 11 , wherein the extrapolated position data of the formation boundary is determined at least partially based on directional data.

15. The system of claim 14 , wherein the directional data is at least one of an inclination of a portion of the bottom hole assembly, an azimuth of the portion of the bottom hole assembly, or a toolface angle of a direction in which the formation boundary is located.

16. The system of claim 11 , wherein the trajectory is adjusted at least partially based on a predefined threshold of a distance between the adjusted trajectory and the formation boundary.

17. The system of claim 11 , wherein the processing system is further configured to perform additional operations comprising:

filtering, by the processing system, at least one of the first formation evaluation data or the second formation evaluation data to generate filtered formation evaluation data; and

determining, by the processing system, the location point of the formation boundary from the filtered formation evaluation data.

18. The system of claim 11 , wherein adjusting the trajectory comprises adjusting a setpoint for a control process to steer the bottom hole assembly.

19. The system of claim 11 , wherein at least one of the first distance or the second distance is at least one of a distance from the bottom hole assembly to the formation boundary, or a true vertical depth of the formation boundary.

20. The system of claim 11 , wherein the computer readable instructions further controls the processing system to generate the extrapolated position data of the formation boundary along a planned trajectory of the wellbore.