The volcanic activities created the Muko-jima and Chichi-jima Island s Archipelago.
Boninite magma occurs.
The plates start to sink.
The Haha-jima Island Archipelago is formed.
Basalt magma occurs.
The plates start to sink.
The volcanic (sulfur) archipelago is formed.
The volcanic activity region moves to the west side.
The plates are sinking even now.
Pillow lava Including Boninite
Submergence Karst on the Periphery of the Minami-jima Island
Dry Scrub Forest (Anijima Island)
Tree Ferns Grown in a Hydrarch Tall Tree Forest (Sekimon)
Columba janthina nitens (Endemic species)