noun
Nankai Trough
A submarine trough located off the southern coast of Japan, known for its potential to generate large earthquakes.
南海トラフ地震は、今後30年以内に高い確率で発生すると予想されている。
A Nankai Trough earthquake is predicted to occur with high probability within the next 30 years.
From 南海 (Nankai, 'South Sea') + トラフ (trough), a geological term for a long, narrow depression on the ocean floor.