The Acoustic Borehole Televiewer provides continuous logs of oriented, unwrapped images of borehole walls. Further processing allows for the computation and display of standard information on fractures and other geological features.
Unlike the Optical Televiewer, the Acoustic Televiewer can be run in both clear and opaque mud.
Unlike the Acoustic Televiewer, the Optical Televiewer can be run in both air filled and (clear) water filled holes. The sonde can be supplied with only a data modem and acquisition software if no other Geovista sondes are required at the time.
Go to the televiewer information page to see some comparison images: Televiewers
Dimensions & Weight: Length: 2.10 m ; Diameter: 42 mm; Weight: 10 kg
Acoustical Subsystem:
Frequency: 1.5 MHz
Beam angle: 3º conical
Rotation speed: up to 20 rev/sec
Sampling density : 90, 120, 180 or 360 per revolution
Acquisition sampling rate: 100 nS
Gain: 0 to 60 dB in 1 dB steps or Automatic Gain Control (AGC)
Acquisition resolution: 8 bits
Deviation Subsystem:
3-axis magnetometer - Azimuth accuracy: ±2.5º
3-axis accelerometer - Inclination accuracy: ±0.4º
Log Parameters:
360° oriented Travel Time Image ( 12-bit resolution / 100 ns per bit )
360° oriented Amplitude Image
Borehole azimuth and dip
Operating Conditions: Fluid filled boreholes; Max. Pressure 20MPa; Max. Temp. 90ºC
Borehole Diameter Range: 50 to over 400 mm , depending on borehole fluid condition