Abstract: The present disclosure relates to a method to calibrate logging measurements from a logging tool for which one or more attributes vary over the course of logging. A logging tool is provided and a pre-logging calibration function for the logging tool is obtained. Logging measurements are made using the logging tool, and a post-logging calibration function for the logging tool is obtained. A variable calibration function using the pre-logging calibration function and the post-logging calibration function is determined, and the logging measurements are calibrated using the variable calibration function. The variable calibration function may be discrete or continuous and linear or non-linear. A non-linear calibration function may be based on measurements of one or more of the varying attributes of the logging tool. A discrete calibration function may have three or more calibration factors.

Abstract: The present disclosure relates to a method to calibrate logging measurements from a logging tool for which one or more attributes vary over the course of logging. A logging tool is provided and a pre-logging calibration function for the logging tool is obtained. Logging measurements are made using the logging tool, and a post-logging calibration function for the logging tool is obtained. A variable calibration function using the pre-logging calibration function and the post-logging calibration function is determined, and the logging measurements are calibrated using the variable calibration function. The variable calibration function may be discreet or continuous and linear or non-linear. A non-linear calibration function may be based on measurements of one or more of the varying attributes of the logging tool. A discreet calibration function may have three or more calibration factors.

Abstract: A method of steering a drilling operation of a well using acoustic measurements. The method includes obtaining, using a central processing unit (CPU), a clean-wet matrix line for the well, where the clean-wet matrix line includes a number of normal compressional values, obtaining, using the CPU, the acoustic measurements from at least one logging while drilling tool at a current depth of the drilling operation, where the acoustic measurements include a compressional to shear velocity ratio and a delta-T compressional measurement, and determining, using the CPU, a current phase of the drilling operation by comparing the acoustic measurements to the clean-wet matrix line. The method further includes, in response to determining that the current phase is not a target phase, generating an updated well trajectory for steering the drilling operation toward the target phase and adjusting the drilling operation using the updated well trajectory.