Determining continuous inclination angle

Abstract

A method for determining an inclination of a wellbore can include receiving sensor data at a rig controller, wherein the sensor data comprises sensor data from a radial magnetometer, a tangential magnetometer, a radial accelerometer, and a tangential accelerometer, determining, via the rig controller, a magnetic toolface angle of a BHA based on the sensor data from the radial magnetometer and the tangential magnetometer, converting, via the rig controller, the magnetic toolface angle to a gravity toolface of the BHA based on the sensor data from the radial accelerometer and the tangential accelerometer; and determining, via the rig controller, an inclination angle based on the gravity toolface, and the sensor data from the radial magnetometer and the tangential magnetometer and determining an azimuth angle based on mapping of the earth's magnetic field vector, the inclination angle, and a high side offset angle.

1 . A method for determining an inclination of a wellbore, the method comprising:
 receiving sensor data at a rig controller, wherein the sensor data was detected by sensors in a logging tool in a bottom hole assembly (BHA) in a wellbore, wherein the sensor data comprises data from a radial magnetometer (b r ), a tangential magnetometer (b τ ), a radial accelerometer (a r ), and a tangential accelerometer (a τ );   determining, via the rig controller, a magnetic toolface angle (φ m ) of the logging tool based on the data from the radial magnetometer (b r ) and the tangential magnetometer (b τ );   converting, via the rig controller, the magnetic toolface angle (φ m ) to a gravity toolface (φ g ) of the logging tool based on the data from the radial accelerometer (a r ) and the tangential accelerometer (a τ ); and   determining, via the rig controller, an inclination angle based on the gravity toolface, and the data from the radial accelerometer (a r ) and the tangential accelerometer (a τ ).   
     
     
         2 . The method of  claim 1 , wherein the sensor data from either one of the radial magnetometer (m r ), the tangential magnetometer (b τ ), the radial accelerometer (a r ), and the tangential accelerometer (a τ ) represent a plurality of sensor data readings from a respective one of the radial magnetometer (b r ), the tangential magnetometer (b τ ), the radial accelerometer (a r ), and the tangential accelerometer (a τ ). 
     
     
         3 . The method of  claim 2 , wherein determining the magnetic toolface angle of the BHA is based on the plurality of the sensor data readings from the radial magnetometer (b r ) and the tangential magnetometer (b τ ). 
     
     
         4 . The method of  claim 3 , wherein converting the magnetic toolface angle to the gravity toolface of the BHA is based on the plurality of the sensor data readings from the radial accelerometer (a r ) and the tangential accelerometer (a τ ). 
     
     
         5 . The method of  claim 4 , wherein determining the inclination angle is based on the gravity toolface, and the plurality of the sensor data readings from the radial accelerometer (a r ) and the tangential accelerometer (a τ ). 
     
     
         6 . The method of  claim 5 , further comprising determining the inclination angle of the wellbore at each of a plurality of incremental distances of a measured depth from a first measured depth of the wellbore to a second measured depth of the wellbore. 
     
     
         7 . The method of  claim 6 , wherein a continuous inclination angle is a profile of the inclination angle from the first measured depth of the wellbore to the second measured depth of the wellbore. 
     
     
         8 . The method of  claim 1 , further comprising:
 determining, via the rig controller, a dogleg severity for a first measured depth of the wellbore, wherein the dogleg severity indicates a rate of change of an inclination angle per an incremental distance along the wellbore.   
     
     
         9 . The method of  claim 1 , further comprising:
 determining, via the rig controller, a plurality of dogleg severities for a respective plurality of measured depths of the wellbore; and   increasing an accuracy of ones of the plurality of dogleg severities that are associated with a portion of the wellbore with an actual inclination angle of less than or equal to 10 degrees when compared to an accuracy of other ones of the plurality of dogleg severities that are associated with a portion of the wellbore with an actual inclination angle of greater than 10 degrees.   
     
     
         10 . The method of  claim 1 , further comprising:
 determining, via the rig controller, a plurality of inclination angles for a respective plurality of measured depths of the wellbore; and   increasing an accuracy of ones of the plurality of inclination angles that are associated with a portion of the wellbore with an actual inclination angle of less than or equal to 10 degrees when compared to an accuracy of other ones of the plurality of inclination angles that are associated with a portion of the wellbore with an actual inclination angle of greater than 10 degrees.   
     
     
         11 . A method for determining an inclination of a wellbore, the method comprising:
 receiving sensor data at a rig controller, wherein the sensor data was detected by sensors in a logging tool in a bottom hole assembly (BHA) in a wellbore, wherein the sensor data comprises data from a radial magnetometer (b r ), a tangential magnetometer (b τ ), a radial accelerometer (a r ), and a tangential accelerometer (a τ );   determining, via the rig controller, an inclination angle profile based on a gravity toolface of the BHA, and the data from the radial accelerometer (a r ) and the tangential accelerometer (a τ ), wherein the inclination angle profile is for a portion of the wellbore with an inclination angle of less than or equal to 10 degrees; and   determining, via the rig controller, a dogleg severity profile based on the inclination angle profile, wherein the dogleg severity of the dogleg severity profile is between +10 degrees/100 feet and −10 degrees/100 feet for the portion of the wellbore.   
     
     
         12 . A method for determining an azimuth angle of a wellbore, the method comprising:
 receiving sensor data at a rig controller, wherein the sensor data was detected by sensors in a logging tool in a bottom hole assembly (BHA) in a wellbore, wherein the sensor data comprises data from a radial magnetometer (b r ), a tangential magnetometer (b τ ), a radial accelerometer (a r ), and a tangential accelerometer (a τ );   determining, via the rig controller, a magnetic toolface angle (φ m ) of the logging tool based on the data from the radial magnetometer (b r ) and the tangential magnetometer (b τ );   converting, via the rig controller, the magnetic toolface angle (φ m ) to a gravity toolface angle (φ g ) of the logging tool based on the data from the radial accelerometer (a r ) and the tangential accelerometer (a τ ) or the data from the axial accelerometer (a ζ );   determining, via the rig controller, an inclination angle (φ ca ) and a high side offset angle (φ hs ) based on the gravity toolface angle (φ 9 ), and the data from the radial accelerometer (a r ) and the tangential accelerometer (a τ ); and   determining, via the rig controller, an azimuth angle (φ ca ) based on mapping of the earth's magnetic field vector (m x , m y , m z ), the inclination angle (φ ci ), and a high side offset angle (φ hs ).   
     
     
         13 . The method of  claim 12 , further comprising:
 determining, via the rig controller, a plurality of azimuth angles based on mapping of the earth's magnetic field vector, a plurality of inclination angles, and a plurality of high side offset angles, wherein the plurality of azimuth angles correspond to a distance between a first measured depth of the wellbore to a second measured depth of the wellbore.   
     
     
         14 . The method of  claim 13 , wherein a continuous azimuth angle is a profile of the plurality of azimuth angles from the first measured depth of the wellbore to the second measured depth of the wellbore. 
     
     
         15 . The method of  claim 12 , further comprising:
 determining, via the rig controller, a first azimuth angle at a first measured depth based on mapping of the earth's magnetic field vector, a first inclination angle at the first measured depth based on first sensor data from the logging tool, and first high side offset angle at the first measured depth based on the first sensor data;   determining, via the rig controller, a second azimuth angle at the first measured depth based on mapping of the earth's magnetic field vector, a second inclination angle at the first measured depth based on second sensor data from a measuring-while-drilling (MWD) survey, and a second high side offset angle at the first measured depth based on the second sensor data;   adjusting gain and offset coefficients for the radial magnetometer, the tangential magnetometer, the radial accelerometer, or the tangential accelerometer until the first azimuth angle substantially equals the second azimuth angle; and   storing the adjusted gain and offset coefficients as calibrated gain and offset coefficients for the radial magnetometer, the tangential magnetometer, the radial accelerometer, and the tangential accelerometer.