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The article presents the results of research concerning electromagnetic (EM) field emitted by rocks during the process of their destruction. The paper describes a measuring stand designed for subjecting rock samples to axial crushing. During the destruction of rock samples, both components of the electromagnetic field emitted by the rock were recorded. The paper presents the results of research on hard coal samples, presenting the obtained time domain waveforms and frequency spectrum of the emitted EM field components. Further potential uses of tests concerned with EM emitted by rocks are determined. Applications registering EM field in mine environments may provide an early mine collapse warnings.

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This article presents the design of an innovative receiver capable of identifying electric and magnetic components of electromagnetic fields. The receiver senses and records electromagnetic disturbances generated as mine tunnels collapse. It offers excellent operating specification and the ability to sense and log magnetic and electrical component strength values in real time. The paper analyzes the data obtained with the use of a system installed in a working mine and attempts to determine hazards resulting from increased rock stress levels that, cause spontaneous EM emissions.

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