Patent ID: 8245795
Filing Date: 2012-08-21
Classification: E21B,G01V

Abstract:
1. A method of steering a drilling operation of a well using acoustic measurements, comprising: obtaining, using a central processing unit (CPU), a clean-wet matrix line for the well, wherein the clean-wet matrix line comprises a plurality 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, wherein the acoustic measurements comprise a compressional to shear velocity ratio and a delta-T compressional measurement; generating an earth model using a plurality of subsurface measurements; updating the earth model using the compressional to shear velocity ratio and the delta-T compressional measurement to obtain an updated earth model; determining, using the CPU, a current phase of the drilling operation by comparing the acoustic measurements to the clean-wet matrix line; in response to determining that the current phase is not a target phase, generating, using the updated earth model, an updated well trajectory for steering the drilling operation toward the target phase; and adjusting the drilling operation using the updated well trajectory.