[M-IS02] Interdisciplinary studies on pre-earthquake processes

★ [MIS02-11] Multiple seismo-anomalies associated with three major earthquakes in China, Japan and Taiwan

*Chieh-hung CHEN¹, Xiaoping ZENG², Katsumi HATTORI³, Jann-yenq LIU⁴ (1.Department of Earth and Environmental Sciences, National Chung Cheng University, Chiayi 621, Taiw, 2.Institute of Geophysics, China Earthquake Administration, Beijing 100081, China, 3.Graduate School of Science, Chiba University, Inage, Chiba 263-8522, Japan, 4.Institute of Space Science, National Central University, Jhongli 320, Taiwan)

Keywords:Groundwater, Electromagnetic field, Total electron content, Crustal deformation, Earthquake forecast

Seismo-crustal deformation, groundwater (containing levels, temperature and radon), geomagnetic and ionospheric anomalies are integrated together to investigate pre-earthquake anomalous phenomena associated with the M6.1 Ludian earthquake, China, the M9.0 Tohoku-Oki earthquake, Japan and the M7.6 Chi-Chi earthquake, Taiwan. Seismo-crustal deformation and groundwater anomalies generally lead the other promising parameters because stress accumulation in crust is one of the major driving forces of earthquakes. Uplift and depression groundwater levels are exactly related with compression and tension stress loading in the crust, respectively. Decreases of groundwater temperature and radon concentration are resulted from uplift groundwater levels. Meanwhile, groundwater would infuse into fracture zones of faults once cracks are developed before earthquakes that can enhance conductivity near hypocenters and/or faults affecting electromagnetic fields and electron total electron contents in the ionosphere. Those aforementioned relationships can be utilized to eliminate anomalies which are unrelated with earthquakes to further increase of the accuracy and understand causal mechanisms of pre-earthquake anomalous phenomena in seismogenic processes.