The 1586 Tensho earthquake occurred around the western part of central Japan. The magnitude is estimated to be around 8, as large as the 1891 Nohbi earthquake, mainly based on the intensity distribution map. However, historical documents concerning the precise damage and detailed crustal deformation etc. for this event are fairly limited as the occurrence time was during the Warring State Period.
The Shokawa fault zone, Atera fault zone and Yoro-Kuwana-Yokkaichi fault zone, typical leading active faults having high activity and fresh topographical expression in central Japan, have been considered to be major candidates for the active faults which produced this great earthquake. The mysterious Tensho earthquake was selected as the main theme of a symposium held in Japanese Society for Active Fault Studies 2010 Fall Meeting, and was discussed in the oral session, based on the recent various data obtained by the investigations for these fault zones after the 1995 Hyogo-ken Nanbu (Kobe) earthquake (M7.3).