Nankai Trough

Trough off the coast of Japan

The Nankai Trough (南海トラフ, Nankai Torafu; Southern Sea Trough) is a submarine trough located south of the Nankaidō region of Japan's island of Honshu, extending approximately 900 km (559 mi) offshore. The underlying fault, the Nankai megathrust, is the source of the devastating Nankai megathrust earthquakes, while the trough itself is potentially a major source of hydrocarbon fuel, in the form of methane clathrate. In plate tectonics, the Nankai Trough marks a subduction zone that is caused by subduction of the Philippine Sea plate beneath Japan, part of the Eurasian plate (Kanda et al., 2004).

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