36°34′12″N 140°25′48″E / 36.570°N 140.430°E
The Idosawa Fault (井戸沢断層, Idozawa Dansō),[1] also referred to as the Shionihara Fault, is an active earthquake fault system located in Fukushima Prefecture of Japan, to the west of Iwaki city. It mainly consists of a trace of three separate striations.