Patterns in the electromagnetic pulsed radiation of alkali halide crystals and rocks

An experimental study is made of general patterns of EMR in the radio frequency range of crystal samples and rocks in the process of their uniform loading to the point at which a major rupture crack forms which destroys the sample. A special laboratory device was used for this which permits us to record the frequency of the pulse trace, the amplitude, and the spectral composition (from 1 to 20 MHz) in the loading process, as well as allowing observation and photographing of the individual pulse shape. Based on the results of experimental studies, the following conclusions may be drawn. (1.) Electromagnetic radiation of alkali halide crystals and rocks bears a pulsed character. (2.) Each rock has its own characteristic frequency range of EMR generation. (3.) Brittle and plastic rocks differ with respect to the character of electromagnetic emission; a more uniform increase in the rate of EMR generation at low-amplitudes is characteristic of plastic rocks. Brittle rocks give higher-amplitude signals, and a sharp increase in pulse count is observed immediately before the destruction of the sample.