High Resolution Acoustic Televiewer
The HRAT (High Resolution Acoustic Televiewer) provides a continuous high-resolution oriented ultrasound image of the borehole wall.
The probe uses a fixed acoustic transducer and a rotating acoustic mirror to scan the borehole walls with a focussed ultrasound beam. The amplitude and travel time of the reflect
Features such as fractures reduce the reflected amplitude and appear as dark sinusoidal traces on the log. The travel-time log is equivalent to a high-precision 360-arm caliper and shows diameter changes within open fractures and ‘break-outs’. Directional information is also recorded and used to orient the images in real time.