The Cross Dipole Sonic (CDS) tool measures the formation compressional and shear slowness in both fast and slow formations and records full waveform data from which shear anisotropy, geomechanical and geophysical properties, permeability and fractures can be detected and quantified.
The Cross Dipole Sonic is a multi-mode acoustic logging tool with four user-selectable modes that can be run together on a single pass: high frequency monopole (for compressional and fast shear determination), low frequency monopole (for Stoneley analysis), X-Y dipole (for shear determination in both fast and slow formations) with in-line and off-line receivers (for shear anisotropy analysis). The dipoles can be run at one of three frequencies in order to optimise data quality in different slowness ranges.
- Formation and reservoir characterization – determine location, orientation and intensity of natural fractures
- Evaluate hydraulic fractures – provide the direction, vertical extent and degree of induced fracture anisotrophy