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The Global Volcanism Program has no activity reports for Kita-Bayonnaise.
The Global Volcanism Program has no Weekly Reports available for Kita-Bayonnaise.
The Global Volcanism Program has no Bulletin Reports available for Kita-Bayonnaise.
The large submarine Kita-Bayonnaise (North Bayonnaise) submarine caldera, also known as Myojin Knoll, lies between the Aogashima and Myojinsho (also called Beyonesu Rocks) calderas in the Izu-Bonin arc. The 6-7 km wide caldera, one of nine along this arc, has walls 500-900 m high. The high point on the western rim is a pumice-mantled remnant of the pre-collapse volcanic complex that reaches a depth of 360 m. The caldera walls reveal rhyolitic lava flows, shallow intrusions, and volcaniclastic deposits. A voluminous blanket of coarse rhyolitic pumice from the caldera-forming eruption mantles the rim and 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.
The Global Volcanism Program is not aware of any Holocene eruptions from Kita-Bayonnaise. If this volcano has had large eruptions (VEI >= 4) prior to 10,000 years ago, information might be found on the Kita-Bayonnaise page in the LaMEVE (Large Magnitude Explosive Volcanic Eruptions) database, a part of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.
|Kita-Beyonesu | Myojin Knoll|
|Feature Name||Feature Type||Elevation||Latitude||Longitude|
|Sunrise||Thermal||-1350 m||32° 6' 0" N||129° 52' 0" E|
|The submarine topography of the 6-7 km wide Myojin Knoll caldera is seen in this Sea-Beam image viewed from the SW. The white line marks the E-W track of the survey vessel. A voluminous blanket of coarse rhyolitic pumice from the caldera-forming eruption mantles the caldera rim and its outer flanks. A post-caldera lava dome rises 250 m above the caldera floor. An active hydrothermal vent field lies on the eastern caldera floor and has produced a polymetallic sulfide deposit extraordinarily rich in gold and silver.
Image by Fumitoshi Murakami (Geological Survey of Japan, courtesy of Richard Fiske, Smithsonian Institution).
The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.
Fiske R S, Naka J, Iizasa K, Yuasa M, 1995. Caldera-forming submarine pyroclastic eruption at Myojin Knoll, Izu-Bonin Arc. JAMSTEC J Deep Sea Res, 11: 315-322.
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: 813-824.
Yuasa M, Nohara M, 1992. Petrographic and geochemical along-arc variations of volcanic rocks on the volcanic front of the Izu-Ogasawara (Bonin) Arc. Bull Geol Surv Japan, 43: 421-456.