Type:		Journal, Article
Title:		Pre-earthquake magnetic pulses
Author(s):		Scoville, J.; Heraud, J.; Freund, F.
Date:		2015
Abstract:		A semiconductor model of rocks is shown to de- scribe unipolar magnetic pulses, a phenomenon that has been observed prior to earthquakes. These pulses are suspected to be generated deep in the Earth's crust, in and around the hypocentral volume, days or even weeks before earth- quakes. Their extremely long wavelength allows them to pass through kilometers of rock. Interestingly, when the sources of these pulses are triangulated, the locations coincide with the epicenters of future earthquakes. We couple a drift-diffusion semiconductor model to a magnetic field in order to de- scribe the electromagnetic effects associated with electrical currents flowing within rocks. The resulting system of equa- tions is solved numerically and it is seen that a volume of rock may act as a diode that produces transient currents when it switches bias. These unidirectional currents are ex- pected to produce transient unipolar magnetic pulses similar in form, amplitude, and duration to those observed before earthquakes, and this suggests that the pulses could be the result of geophysical semiconductor processes.
Journal (full):		Natural Hazards and Earth Systems Science
Volume:		15
Start Page:		1873
End Page:		1880
Link:		http://www.nat-hazards-earth-syst-sci.net/15/1873/2015/nhess-15-1873-2015.pdf