Abstract: Various implementations directed to correction of rotation rate measurements are provided. In one implementation, a method may include receiving rotation rate measurements about a first axis and a second axis from first gyroscopic sensors. The method may include receiving a first rotation rate measurement about a third axis from a second gyroscopic sensor. The method may include determining an estimated rotation rate measurement about the third axis based on the rotation rate measurements about the first axis and the second axis. The method may include determining a bias value based on a difference between the first rotation rate measurement about the third axis and the estimated rotation rate measurement. The method may include receiving second rotation rate measurements about the third axis from the second gyroscopic sensor. The method may include correcting the second rotation rate measurements about the third axis based on the determined bias value.

Abstract: A method and an apparatus are provided for determining an orientation of a tool with respect to a reference direction. The tool is configured to be moved along a wellbore and to generate information usable to determine an orientation of the tool. At least one first signal is indicative of an orientation of a directional reference system with respect to the reference direction. Information regarding a relative orientation of the tool with respect to the directional reference system is used to determine the orientation of the tool with respect to the reference direction in response at least in part to the at least one first signal.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: Various implementations described herein are directed to a method for surveying a wellbore. A statistical estimation process that combines magnetic survey measurement data and gyroscopic survey measurement data to form error estimates in a magnetic survey system is applied. The error estimates are used to correct magnetic survey data provided by the magnetic survey system. Magnetic only survey data is used when convergence of the error estimates has occurred. Information that facilitates drilling the wellbore is provided.

Abstract: Various implementations described herein are directed to a method for surveying a wellbore. A statistical estimation process that combines magnetic survey measurement data and gyroscopic survey measurement data to form error estimates in a magnetic survey system is applied. The error estimates are used to correct magnetic survey data provided by the magnetic survey system. Magnetic only survey data is used when convergence of the error estimates has occurred. Information that facilitates drilling the wellbore is provided.

Abstract: Various implementations directed to a continuous survey using magnetic sensors are provided. In one implementation, a method may include acquiring continuous survey data during an outrun data acquisition using a survey tool disposed within a previously drilled section of a wellbore. The survey tool may have one or more magnetic sensors, and the survey tool may be configured to ascend within the previously drilled section of the wellbore during the outrun data acquisition. The method may further include transmitting the continuous survey data to a computing system, where the computing system may be configured to generate a continuous survey of the previously drilled section of the wellbore based on the continuous survey data.

Abstract: Various implementations directed to a continuous survey using magnetic sensors are provided. In one implementation, a method may include acquiring continuous survey data during an outrun data acquisition using a survey tool disposed within a previously drilled section of a wellbore. The survey tool may have one or more magnetic sensors, and the survey tool may be configured to ascend within the previously drilled section of the wellbore during the outrun data acquisition. The method may further include transmitting the continuous survey data to a computing system, where the computing system may be configured to generate a continuous survey of the previously drilled section of the wellbore based on the continuous survey data.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: Various implementations directed to correction of rotation rate measurements are provided. In one implementation, a method may include receiving rotation rate measurements about a first axis and a second axis from first gyroscopic sensors. The method may include receiving a first rotation rate measurement about a third axis from a second gyroscopic sensor. The method may include determining an estimated rotation rate measurement about the third axis based on the rotation rate measurements about the first axis and the second axis. The method may include determining a bias value based on a difference between the first rotation rate measurement about the third axis and the estimated rotation rate measurement. The method may include receiving second rotation rate measurements about the third axis from the second gyroscopic sensor. The method may include correcting the second rotation rate measurements about the third axis based on the determined bias value.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: A system and method for providing information regarding the tortuosity of a wellbore path is provided. The method includes receiving data from a plurality of survey stations of a wellbore survey. The method further includes determining a plurality of tortuosity parameter values for the wellbore path within a corresponding plurality of analysis windows, wherein each analysis window has at least one tortuosity parameter value.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: Systems and methods for monitoring the tool rotation of a survey tool within a wellbore during a gyrocompassing survey measurement are provided. A plurality of signals from at least one accelerometer module of the survey tool is indicative of measurements of the Earth's gravitation vector taken by the at least one accelerometer module during the gyrocompassing survey measurement. The plurality of signals is used to calculate a tool face rate of change of the survey tool with respect to the wellbore during the gyrocompassing survey measurement.

Abstract: A method and an apparatus are provided for determining an orientation of a tool with respect to a reference direction. The tool is configured to be moved along a wellbore and to generate information usable to determine an orientation of the tool. At least one first signal is indicative of an orientation of a directional reference system with respect to the reference direction. Information regarding a relative orientation of the tool with respect to the directional reference system is used to determine the orientation of the tool with respect to the reference direction in response at least in part to the at least one first signal.

Abstract: Systems and methods are provided for producing a continuous survey of a previously drilled portion of a wellbore. The method includes receiving a plurality of stationary survey measurements taken at a corresponding plurality of locations along the portion of the wellbore. The method further includes receiving at least one continuous survey including a plurality of continuous survey measurements taken between a pair of stationary survey measurements of the plurality of stationary survey measurements. The method further includes combining the plurality of stationary survey measurements and the plurality of continuous survey measurements to produce the continuous survey of the portion of the wellbore.

Abstract: Systems and methods for monitoring the tool rotation of a survey tool within a wellbore during a gyrocompassing survey measurement are provided. A plurality of signals from at least one accelerometer module of the survey tool is indicative of measurements of the Earth's gravitation vector taken by the at least one accelerometer module during the gyrocompassing survey measurement. The plurality of signals is used to calculate a tool face rate of change of the survey tool with respect to the wellbore during the gyrocompassing survey measurement.

Abstract: A system and method for providing information regarding the tortuosity of a wellbore path is provided. The method includes receiving data from a plurality of survey stations of a wellbore survey. The method further includes determining a plurality of tortuosity parameter values for the wellbore path within a corresponding plurality of analysis windows, wherein each analysis window has at least one tortuosity parameter value.

Abstract: A system and method for providing information regarding the tortuosity of a wellbore path is provided. The method includes receiving data from a plurality of survey stations of a wellbore survey. The method further includes defining a plurality of reference lines for the wellbore path. The method further includes determining a plurality of displacements of the wellbore path from the plurality of reference lines.