Natural Hazards and Earth System Science www.nat-hazards-earth-syst-sci.net 1561-8633 1684-9981 7 1 2007 10.5194/nhess-7-149-2007 http://www.nat-hazards-earth-syst-sci.net/7/149/2007/ http://www.nat-hazards-earth-syst-sci.net/7/149/2007/nhess-7-149-2007.html http://www.nat-hazards-earth-syst-sci.net/7/149/2007/nhess-7-149-2007.pdf 149 154 2007-01-26 Electric signal emissions during repeated abrupt uniaxial compressional stress steps in amphibolite from KTB drilling D. Triantis triantis@ee.teiath.gr C. Anastasiadis F. Vallianatos P. Kyriazis G. Nover Technological Educational Institution of Athens, Athens, Greece Technological Educational Institute of Crete, Chania, Greece Brunel University, Uxbridge, London, UK Mineralogisches Institut der Universität Bonn, Germany Laboratory experiments have confirmed that the application of uniaxial stress on rock samples is accompanied by the production of weak electric currents, to which the term Pressure Stimulated Currents – PSC has been attributed. In this work the PSC emissions in amphibolite samples from KTB drilling are presented and commented upon. After having applied sequential loading and unloading cycles on the amphibolite samples, it was ascertained that in every new loading cycle after unloading, the emitted PSC exhibits lower peaks. This attitude of the current peaks is consistent with the acoustic emissions phenomena, and in this work is verified for PSC emissions during loading – unloading procedures. 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