Itoigawa-Shizuoka Tectonic Line


Itoigawa-Shizuoka Tectonic Line, also Ito Shizu Sen is a major fault zone on Honshu island running from Itoigawa, Niigata Prefecture, through Lake Suwa, and on to Shizuoka in Shizuoka Prefecture. It is often confused with the Fossa Magna, a geological feature it forms the western boundary of.

Seismic activity

Recent significant earthquakes on this tectonic line include:M5.4; 30 June 2011; epicentre near Matsumoto, Nagano; 1 death, 17 injuries.