Does a Caldera Form the Islands of the Four Mountains, Alaska?

Islands of the Four Mountains with volcanoes named.  Image courtesy Quantum Spatial Photo, via Power, et al, Dec 2020 via Volcano Discovery

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Kulshan Caldera and Mount Baker Volcanic Field, Washington State, USA

Glaciated Mount Baker from neighboring Mount Shuksan.  Area to the right is the Kulshan Caldera.  Jagged peak is glacially eroded basalts of Mount Shukshan.  Image courtesy Lee Siebert, 1971, Smithsonian GVP

Lassen Volcanic Center, California

Skyline above timberline of the Lassen dome field.  Major domes visible.  Cinder Cone is in the foreground, the most recent feature.  Lassen Peak in the center background.  Other recent domes labeled.  Image courtesy Lassen Volcanic Center, USGS

Mount Martin and Alagogshak Volcanoes, Katmai, Alaska

Summit of Mount Martin showing active fumaroles and small acidic lake.  Image courtesy SR Wood, US NPS, Katmai

The Atka, Korovin, Kliuchef Volcanic Complex, Aleutians, Alaska

Greater Atka Volcano complex with the caldera, Korovin and Kliuchef labeled. Image courtesy Lu and Dzurisin, 2014, via Smithsonian GVP

El Estribo Volcanic Complex, Mexico

El Estribo (red marker) volcano.  Cinder cone topping the shield is just to the south of the marker.  Fault scarp / flank collapse scarp visible to the left and right of the marker.  Neighboring Patzcuaro is the settled area to the right.  Southern end of Patzcuaro Lake is visible at top.  Screen capture from Google maps

Indian Heaven Volcanic Field, Washington State, USA

Lemei Rock in Indian Heaven volcanic field.  Image courtesy Outdoor Project, Fall Color in Indian Heaven Wilderness, WA, Lisa Holmes, 2014

Dotsero Volcanic Complex, Colorado, USA

Remaining maar of Dotsero volcanic complex.  Image courtesy Our Community Nov, 2019

Dotsero is the most recent of four quaternary volcanic centers in NW Colorado.  The locations and relative ages are: Dotsero (4,150 years ago), Willow Peak (undated), McCoy (0.64 Ma) and Triangle Peak (1.98 – 1.87 Ma).  Triangle Peak was the only one of these not monogenetic as it produced at least 11 lava flows before activity stopped.  Willow Peak is described as a young cinder cone with a narrow lava flow extending 6 – 7 km E.

Nevado de Toluca, Mexico

Nevado de Toluca from surrounding valley.  Image courtesy Ricardo Guaderrama Caraveo, via Medium.com, 2018

Recent Activity at Little Sitkin, Alaska

NASA Landsat image of Little Sitkin island. Image courtesy SJ Smith via AVO, 2001