Full-Waveform / Compensated Sonic Probe

The RG sonic probe uses a dual-transmitter
dual-receiver array to provide high-quality formation acoustic-velocity data. Options are available for display of full-waveform data and cement-bond data (CBL) in cased boreholes.

PRINCIPLE OF MEASUREMENT
A piezoelectric transmitter is stimulated by a
high-voltage pulse and radiates a high-frequency sonic wave via the borehole fluid and formation to a receiver. An accurate quartz clock measures the first arrival transit time.
Compensated sonic mode: 
Both pairs of transmitters and receivers are used. The probe measures the velocity of the first compressional arrival. Use of multiple transmitters and receivers allows cancellation of the borehole fluid path and determination of formation velocity.
Full waveform sonic mode:
  Only the lower transmitter is used. The probe records the full sonic wave-train at both receivers simultaneously and also the velocity of the first arrival.
Cement-bond log (CBL) mode:
Only the lower transmitter is used. The probe records the amplitude and arrival time of the first casing arrival at the lower receiver and full wave-trains at both receivers.