Abstract: A computer-based method of generating a survey of a wellbore section is provided. The method includes analyzing a plurality of surveys of the wellbore section to identify survey measurements that do not comprise gross errors, generating an initial weighted average survey, and calculating an initial set of measurement differences between the identified survey measurements and the initial weighted average survey. The method further includes calculating a plurality of error term estimates for the plurality of surveys and using the plurality of error term estimates to correct the identified survey measurements. The method further includes generating an updated weighted average survey and calculating an updated set of measurement differences between the identified survey measurements and the updated weighted average survey.

Abstract: An apparatus and method for measuring depth, velocity, or both depth and velocity of instrumentation along a wellbore is provided. The apparatus includes a downhole portion movable within the wellbore in a direction generally parallel to the wellbore. The apparatus further includes a first acceleration sensor that generates a first signal indicative of a first acceleration. The apparatus further includes a second acceleration sensor that generates a second signal indicative of a second acceleration. The apparatus further includes a bend sensor generating a third signal indicative of an amount of bend of at least a portion of the downhole portion.

Abstract: A computer-based method of generating a survey of a wellbore section is provided. The method includes analyzing a plurality of surveys of the wellbore section to identify survey measurements that do not comprise gross errors, generating an initial weighted average survey, and calculating an initial set of measurement differences between the identified survey measurements and the initial weighted average survey. The method further includes calculating a plurality of error term estimates for the plurality of surveys and using the plurality of error term estimates to correct the identified survey measurements. The method further includes generating an updated weighted average survey and calculating an updated set of measurement differences between the identified survey measurements and the updated weighted average survey.

Abstract: An apparatus and method for measuring depth, velocity, or both depth and velocity of instrumentation within a wellbore is provided. The apparatus includes a downhole portion movable within the wellbore in a direction generally parallel to the wellbore. The apparatus further includes a first acceleration sensor mounted at a first position within the downhole portion. The first acceleration sensor generates a first signal indicative of a first acceleration in a first direction generally parallel to the wellbore at the first position. The apparatus further includes a second acceleration sensor mounted at a second position within the downhole portion. The second acceleration sensor generates a second signal indicative of a second acceleration in a second direction generally parallel to the wellbore at the second position. The apparatus further includes a bend sensor generating a third signal indicative of an amount of bend of at least a portion of the downhole portion.

Abstract: An apparatus and method for measuring depth, velocity, or both depth and velocity of instrumentation within a wellbore is provided. The apparatus includes a downhole portion movable within the wellbore in a direction generally parallel to the wellbore. The apparatus further includes a first acceleration sensor mounted at a first position within the downhole portion. The first acceleration sensor generates a first signal indicative of a first acceleration in a first direction generally parallel to the wellbore at the first position. The apparatus further includes a second acceleration sensor mounted at a second position within the downhole portion. The second acceleration sensor generates a second signal indicative of a second acceleration in a second direction generally parallel to the wellbore at the second position. The apparatus further includes a bend sensor generating a third signal indicative of an amount of bend of at least a portion of the downhole portion.

Abstract: An apparatus and method for measuring depth, velocity, or both depth and velocity of instrumentation within a wellbore is provided. The apparatus includes a downhole portion movable within the wellbore in a direction generally parallel to the wellbore. The apparatus further includes a first acceleration sensor mounted at a first position within the downhole portion. The first acceleration sensor generates a first signal indicative of a first acceleration in a first direction generally parallel to the wellbore at the first position. The apparatus further includes a second acceleration sensor mounted at a second position within the downhole portion. The second acceleration sensor generates a second signal indicative of a second acceleration in a second direction generally parallel to the wellbore at the second position. The apparatus further includes a bend sensor generating a third signal indicative of an amount of bend of at least a portion of the downhole portion.

Abstract: An apparatus and method for measuring depth, velocity, or both depth and velocity of instrumentation within a wellbore is provided. The apparatus includes a downhole portion movable within the wellbore in a direction generally parallel to the wellbore. The apparatus further includes a first acceleration sensor mounted at a first position within the downhole portion. The first acceleration sensor generates a first signal indicative of a first acceleration in a first direction generally parallel to the wellbore at the first position. The apparatus further includes a second acceleration sensor mounted at a second position within the downhole portion. The second acceleration sensor generates a second signal indicative of a second acceleration in a second direction generally parallel to the wellbore at the second position. The apparatus further includes a bend sensor generating a third signal indicative of an amount of bend of at least a portion of the downhole portion.