We have investigated the mode of emplacement of iconic Devils Tower, which is a phonolite porphyry monolith in the state of Wyoming in the western United States. Our field survey of this structure and its geological setting, its radiometric dating, and the tectonomagmatic evolution of the region suggest a new genetic interpretation of the volcaniclastic rocks in the area and provide a basis for a new hypothetical emplacement scenario for Devils Tower. This interpretation was inspired by an analogy of the tower with a similar phonolite butte in the Cenozoic volcanic region of the Czech Republic and analogue modeling using plaster of paris combined with finite element thermal numerical modeling. Our results indicate that Devils Tower is a remnant of a coulée or low lava dome that was emplaced into a broad phreatomagmatic crater at the top of a maar-diatreme volcano.
- Received 5 August 2014.
- Revision received 18 November 2014.
- Accepted 13 January 2015.
- © 2015 Geological Society of America