Figure F4. Dipole Shear Sonic tool (DSI) for acoustic logging (figure taken from Borehole Research Group), consisting of a transmitter section, an isolation joint, and a linear array of eight receivers (spacing = 6 in). Overall length = 15.5 m. A monopole source is driven in high and low frequencies for the generation of P- and S-waves and in a low frequency for Stoneley waves. The dipole excites flexural waves for S-wave velocity determination in soft formations.

Figure F4. Dipole Shear Sonic tool (DSI) for acoustic logging (figure taken from Borehole Research Group), consisting of a transmitter section, an isolation joint, and a linear array of eight receivers (spacing = 6 in). Overall length = 15.5 m. A monopole source is driven in high and low frequencies for the generation of P- and S-waves and in a low frequency for Stoneley waves. The dipole excites flexural waves for S-wave velocity determination in soft formations.