Myojin Knoll volcano

submarine volcano -360 m / -1,181 ft
Izu Islands, Japan, 32.1°N / 139.85°E
Current status: normal or dormant (1 out of 5)

Myojin Knoll volcano is a large submarine caldera between Aoga-shima and Bayonnaise Rocks volcanoes in the Izu-Bonin arc. The volcano contains a 6-7 km wide and up to 900 m deep caldera with steep walls.
The highest point on the western caldera rim is a pumice-mantled remnant of the cone before the caldera formation, and reaches to a depth of 360 m. The eruption that formed the caldera could have been only a few thousand years ago.

Show interactive Map
[hide map] [enlarge]
Typical eruption style: explosive
Myojin Knoll volcano eruptions: unknown

Latest nearby earthquakes

No recent earthquakes
TimeMag. / DepthDistance/Location

Background

The walls of the caldera, also known as Kita-Bayonnaise (North Bayonnaise) reveal rhyolitic lava flows, shallow intrusions, and volcaniclastic deposits. A voluminous blanket of coarse rhyolitic pumice from the caldera-forming eruption mantles the caldera rim and its outer flanks.
Post-caldera eruptions formed a lava dome that rises 250 m above the caldera floor. The age of the caldera is not known, but was considered by Fiske et al. (2001) to perhaps be as young as a few thousand years. An active hydrothermal vent field lies on the eastern caldera floor and has produced a polymetallic sulfide deposit from vent chimneys up to 30 m high that emit fluids as hot as 278 degrees C.
---
Reference cited:
Fiske R S, Naka J, Iizasa K, Yuasa M, Klaus A (2001) "Submarine silicic caldera at the front of the Izu-Bonin arc, Japan: voluminous seafloor eruptions of rhyolite pumice.", Geol Soc Amer Bull, 113, pp 813-824

(from: Smithsonian / GVP volcano information)


See also: Sentinel hub | Landsat 8
Show more
Try our free app!
Volcanoes & Earthquakes - new app for Android
Android | iOS version

More on VolcanoDiscovery

Why is there advertising on this site?
Support us - Help us upgrade our services!
We truly love working to bring you the latest volcano and earthquake data from around the world. Maintaining our website and our free apps does require, however, considerable time and resources.
We need financing to increase hard- and software capacity as well as support our editor team. We're aiming to achieve uninterrupted service wherever an earthquake or volcano eruption unfolds, and your donations can make it happen! Every donation will be highly appreciated. If you find the information useful and would like to support our team in integrating further features, write great content, and in upgrading our soft- and hardware, please make a donation (PayPal or Online credit card payment).

Planned features:
  • Weather reports
  • Tsunami alerts
  • Design upgrades
  • Faster responsiveness
Thanks to your past donations, these features have been added recently:
  • Earthquake archive from 1900 onwards
  • Additional seismic data sources
  • Improved content in English
Download and Upgrade the Volcanoes & Earthquakes app to get one of the fastest seismic and volcano alerts online:
Android | IOS
Thank you!
Copyrights: VolcanoDiscovery and other sources as noted.
Use of material: Most texts and images, in particular photographs, on this website are protected by copyright. Further reproduction and use of without authorization is usually not consented. If you are not sure or need licensing rights for photographs, for example for publications and commercial use, please contact us.