Study of earthquake location using electromagnetic precursors

A technique to locate earthquake hypocenters using extremely low frequency (ELF) electromagnetic (EM) precursors is proposed. This technique relies on recording EM eruptions caused by underground physical mechanisms during the earthquake preparing process. Using the triangulation algorithm and the attenuation rate of EM waves in the Earth-ionosphere system, the source (usually the earthquake hypocenter) can be located. During the locating process, the attenuation rate of EM waves in local regions is modified in order to improve accuracy of result. Based on this technique, simulations are carried out using the geodesic finite difference time-domain (G-FDTD) method. Results show that the locating error is within one cell of the FDTD method.