ABSTRACT
The echometric surveillance of caverns is especially important with regards to their safe and effective operation. As opposed to brine production caverns, storage caverns are generally subject only to convergence and do not undergo large and irregular changes of shape under normal conditions. Echometric surveillance is therefore primarily employed to obtain proof of the cavern stability and convergence.
Applying the state-of-the-art tool technology it is possible during an echometric survey to measure and process besides the geometry all relevant parameters such as speed of sound, pressure and temperature with a single tool run. Only when considering the physical parameters it is possible to achieve high-accurate results from sonar surveys.
To support rock-mechanical evaluations it is sometimes advantageous to make measurements for specific regions of a cavern with a higher density of measuring points. So-called spiral measurements as well as surveys with an extremely high measuring point density can provide very accurate and detailed information.
In the first instance of the presentation the techniques used for surveying caverns as well as the survey procedure are described in general. Subsequently some interesting results of sonar surveys in regard to rock-mechanical evaluations and questions are presented.
