Oki Islands
A feature of the southwestern Sea of Japan is a deep, developing continental shelf. The eastern Oki Islands, a big ridge of three rows lines up in parallel to the Japanese archipelago, and it connects with a Yamato Basin which has expanded from Oki Islands and offshore of the Tōhoku region to the south in between those. The vast Tsushima Basin has extended on the tip of the Oki offshore that expands from Oki Islands on the north side.