| 摘要 |
<p>PURPOSE: To measure a stratum speed as the function of the azimuth around a hole by receiving the sound waves transmitted into the stratum at a plurality of the azimuths. CONSTITUTION: In a sonde 11, which is suspended from a wire cable by an acoustic stratum detecting tool 10, the compressed waves generated by one or more transmitters 20 are received by one or more receivers 25. The pressure signals are transmitted to the ground surface with the cable 12 and processed by a processor 30. The processor 30 is also used for tracking the depth of the sonde 11 in a hole 14. The sonde 11 has, e.g. a segmented one cylindrical transmitter 120a and segment cylindrical receivers 125a and 127a , which are separated into two parts in the axial direction. Segments 120a -1 to 120a -3 of the transmitter 120a are sequentially activated by electronic control. Corresponding segments 125a -1 to 125a -3 and 127a -1 to 127a -3 record the arriving waveforms. The respective segments are located at the different azimuths around the hole 14. The speeds for the stratum 16 at these azimuths are determined by discriminating the arrivals of the compressed waves.</p> |
