Kikai (Japan)

Status Minor Eruption 2013 704m
Caldera (Subduction zone / Oceanic crust (< 15 km))

Kikai is a mostly submerged, 19-km-wide caldera near the northern end of the Ryukyu Islands south of Kyushu. Kikai was the source of one of the world's largest Holocene eruptions about 6300 years ago. Rhyolitic pyroclastic flows traveled across the sea for a total distance of 100 km to southern Kyushu, and ashfall reached the northern Japanese island of Hokkaido. The eruption devastated southern and central Kyushu, which remained uninhabited for several centuries. Post-caldera eruptions formed Iodake lava dome and Inamuradake scoria cone, as well as submarine lava domes. Historical eruptions have occurred in the 20th century at or near Satsuma-Iojima (also known as Tokara-Iojima), a small 3 x 6 km island forming part of the NW caldera rim. Showa-Iojima lava dome (also known as Iojima-Shinto), a small island 2 km east of Tokara-Iojima, was formed during submarine eruptions in 1934 and 1935. Mild-to-moderate explosive eruptions have occurred during the past few decades from Iodake, a rhyolitic lava dome at the eastern end of Tokara-Iojima.

Kikai is a mostly submerged, 19-km-wide caldera south of Kyushu that was the source of one of the world's largest Holocene eruptions about 6300 years ago. Pyroclastic flows traveled across the sea for a total distance of 100 km and devastated southern and central Kyushu. This view from near the summit of the post-caldera cone Iwo-dake shows the western rim of Kikai caldera forming the peninsula (upper left) behind conical Inamura-dake scoria cone.

Photo by Yasuo Miyabuchi, 1996 (Forestry and Forest Products Research Institute, Kyushu).

Last updated 2020-10-06 02:00:02