Determination of the liquid level and sound speed in the hole clearance of the producing well

Reasons for obtaining unreliable results when determining the liquid level in the hole clearance with the use of wave measuring and echo metering techniques are given. The field map of sound speeds produced with the use of direct measurements of sound speed is given. The need to periodically update the sound speed table with the use of the complex of the "SIAM-Maste2C" type is pointed out.