for the fall meeting in a few weeks, it contains some controversial statements:

T34B-01 INVITED
Recent Progress and State of the Art of Seismo-Electromagnetics in Japan

Hattori, K, Dept. of Earth Science, Chiba University

Despite its extreme importance and years of efforts, practical short-term earthquake prediction still remains to be achieved in future. However, earthquake- related electromagnetic phenomena are recently considered as a promising candidate for short-term earthquake prediction. There have been accumulated a lot of evidences of precursory signatures in a wide frequency range (DC-VHF). Measurements of electromagnetic phenomena can be classified into three types; the passive ground-based observation for lithospheric emissions, the ground- based observation with the use of transmitter signals for the study of seismo-atmospheric and –ionospheric perturbations, and the satellite observation. One of the most promising methods among them is a method of detecting seismogenic ULF emissions because there have been reported convincing evidences of ULF magnetic signature. In order to verify electromagnetic phenomena preceding large earthquakes and to clarify the relationship between electromagnetic phenomena and possible physics, sensitive sensors should be installed and sophisticated data analyses should be required. In this paper, state of the art and progress of study seismo-electromagnetics in Japan will be summarized in the three categories. It seems obvious that electromagnetic phenomea occurr prior to large earthquake. And the earthquake-related electromagnetic phenomena have been studied scientifically, which is useful for the short-term earthquake prediction. Several promising methodologies have already been proposed; ULF emissions, radio sounding using subionospheric VLF/LF and VHF waves, GPS monitoring of total electron content, satellite observation of the ionosphere, and remote sensing. It is rather difficult to accumulate ULF events because of local measurements. On the other hand, the integrate observations such as subionospheric VLF/LF and VHF radio sounding measurements and satellite observations have already obtained many events and performend statistical analyses and suggeted significant changes. In the future, complex and well-coordinate observation should be conducted to clarify the generation mechanisms of earthquake–related electromagnetic phenomena including litosphere- atmosphere-ionosphere coupling.