| Abstract: | Presently, salt deposits are used for storage of energy from liquid or gaseous carrier materials. Another application being considered is the storage of radioactive material. In order to avoid possible future environmental risk, extremely high security has to be guaranteed in advance for a long period. Therefore, a very precise exploration is absolutely necessary. Exploration methods already known—which are applicable during and after drilling of test holes—help in the recognition of structures in the salt only in the close vicinity of the holes. Radiowave electromagnetic methods developed for routine measurements in salt mines provide a penetration of some hundred meters. Appropriate well-logging equipment has been designed here for measurements from surface boreholes. Discontinuities around one borehole in the salt can be detected through the electromagnetic reflection method. When measuring between two boreholes, additional reflecting zones can be detected, and attenuation of directly pathed waves can point out material with greater absorption properties between the holes. Additional attempts to use acoustic waves of nearly the same wavelength proved that it is possible to recognize the direction of signals arriving at the receiver and allow separation of P- and S-waves. Instrumentation as well as recent results are reported. |
