About the possibility of using reflected waves for detection of karst cavities

Resumo

Accidents with buildings in Moscow above karst cavities created caused nessesity to detect them with the help of geophysics. The dynamic and kinematic anomalies were simulated and surveyed with the method of photoplastic on the interval of reflection wave's T-D curves. These anomalies were situated in the shadow zone above the karst cavities and created by refraction (enveloping) and diffraction. Wave's T-D curves were built and the complying composite of coupling of diameter cavities and the depth of it's orientation with the time delay of T-D curves and changing of wave's amplitude in the shadow zone. The compositing of this coupling is that if the cavities diameter enlarges, the effect of refraction increases, but the effect of diffraction (enveloping) decreases.