e-Sonic™

E-Sonic Dual Frequency Expanded Mesurement Range Sonic

Building on our existing reliable technology of the CLSS tool, the e-sonic service expands the measurement range of the LWD tool to include slow shear analysis. The measurement range is currently 40 – 340/500 microseconds per foot. The two unipole transmitters excite compressional and shear body waves in hard rock as well as compressional and flexural modes in soft formations. The e-sonic™ tool is a dual frequency LWD sonic tool.

The 15 kHz signal is mainly used for compressional arrival processing and shear analysis in hard rock. The compressional and the shear are computed downhole and are available for transmission to the surface in real-time.

The 7 kHz signal enhances the flexural arrivals and is used for flexural wave processing in softer rock. This processing is provided in the PathFinder computing centers. An advanced dispersion correction algorithm was developed to convert the flexural slowness into the true formation shear slowness. The dispersion algorithm is based on a rigorous solution of the wave equation and uses compressional and shear slownesses together with density, caliper, frequency and borehole fluid parameters to compute the true shear slowness.