Japan Median Tectonic Line

Japan Median Tectonic Line
Red line represents Median Tectonic Line. Orange shaded region is Fossa Magna, bounded by the Itoigawa-Shizuoka Tectonic Line (western blue line).
Country	Japan
Characteristics
Segments	multiple
Displacement	5 mm (0.20 in)/yr to 10 mm (0.39 in)/yr [1]
Tectonics
Status	Active
Earthquakes	Tectonic
Type	right-lateral strike-slip[1]
Movement	8 Mw[2]
Age	Miocene-Holocene
Japanese Active Fault database or search

Japan Median Tectonic Line (中央構造線, Chūō Kōzō Sen), also Median Tectonic Line (MTL), is Japan's longest fault system.^[3][4] The MTL begins near Ibaraki Prefecture, where it connects with the Itoigawa-Shizuoka Tectonic Line (ISTL) and the Fossa Magna. It runs parallel to Japan's volcanic arc, passing through central Honshū to near Nagoya, through Mikawa Bay, then through the Inland Sea from the Kii Channel and Naruto Strait to Shikoku along the Sadamisaki Peninsula and the Bungo Channel and Hōyo Strait to Kyūshū.^[4]

The sense of motion on the MTL is right-lateral strike-slip, at a rate of about 5–10 mm/yr.^[1] This sense of motion is consistent with the direction of oblique convergence at the Nankai Trough. The rate of motion on the MTL is much less than the rate of convergence at the plate boundary, making it difficult to distinguish the motion on the MTL from interseismic elastic straining in GPS data.^[5]