Differentiating between artificial and natural sources of electromagnetic radiation at a seismogenic fault

0564839 - ÚSMH 2023 RIV NL eng J - Journal Article
Baroň, Ivo - Koktavý, P. - Trčka, T. - Rowberry, Matthew David - Stemberk, Josef - Balek, Jan - Plan, L. - Melichar, R. - Diendorfer, G. - Macků, R. - Škarvada, P.
Differentiating between artificial and natural sources of electromagnetic radiation at a seismogenic fault.
Engineering Geology. Roč. 311, DEC 20 (2022), č. článku 106912. ISSN 0013-7952. E-ISSN 1872-6917
R&D Projects: GA MŠMT(CZ) LM2015079
Institutional support: RVO:67985891
Keywords : Electromagnetic radiation * Brittle rock strain * Microcracking * Seismogenic fault * Eastern Alps
OECD category: Geology
Impact factor: 7.4, year: 2022
Method of publishing: Open access
https://www.sciencedirect.com/science/article/pii/S0013795222003970

Ultralow frequency (ULF) to low frequency (LF) electromagnetic radiation represents one of the most promising effects of brittle rock strain and microcracking that might be potentially helpful for short term earthquake forecasting. In this study the results of a six month monitoring campaign are presented from Obir Cave in the eastern Alps. Direct experimental observations of electromagnetic radiation have been made using a customised broadband data logger installed next to the Obir Faultthis seismogenic fault near the Periadriatic Lineament is known to be related to at least three large prehistoric earthquakes. On the basis of these measurements it has been possible to characterise a number of distinct signals: artificial constant narrowband signals at discrete frequencies, short serial broadband impulses, high energy broadband impulses, and low energy broadband im-pulses. The narrowband artificial signals were removed from the electromagnetic radiation time series analysis so that the natural signals were enhanced and could be compared more easily to meteorological parameters and rock strain indicators. Critically, the high energy broadband impulses show a strong correlation with lightning activity across much of central Europe and the eastern Mediterranean while the low energy broadband impulses appear to be associated with local rock strain in and around Obir Cave. Unfortunately, it seems certain that some of the essential strain related impulses are likely to have been overprinted by the larger lightning related impulses.
Permanent Link: https://hdl.handle.net/11104/0336819