Which trench is also known as the Izu-Bonin Trench?

The trench also known as the Izu-Bonin Trench is the Izu-Ogasawara Trench.

The name reflects the region’s geography: “Izu” refers to the Izu Islands south of Japan, while “Bonin” is the historic European name for the Ogasawara Islands. Modern geographic usage often favors Izu-Ogasawara, but Izu-Bonin remains a widely recognized alternative name for the same trench.

It is a western Pacific oceanic trench extending south from the Japan Trench toward the Mariana Trench. The trench marks a subduction zone where the Pacific Plate descends beneath the Philippine Sea Plate. That powerful interaction helped create the Izu-Bonin-Mariana island-arc system, including volcanic islands such as the Izu and Ogasawara groups.

The trench reaches approximately 9,826 m at its deepest point, making it one of the deepest places in the ocean. It should not be confused with the Japan Trench to the north, the Ryukyu Trench farther southwest, or the Mariana Trench farther south. In 2022, a crewed submersible reached its deepest point, and a juvenile snailfish was filmed at 8,336 m.