Fumarole Butte
Background
Fumarole Butte is located in the area once dominated by Lake Bonneville, a massive body of water nearly 19,750 square miles (51,152 km) in area. The lake was created more than 800,000 years ago by extensive precipitation and glacier melting, and has dried up and re-emerged at least 28 times since. The cycles have been matched almost exactly to periods of glaciation by drilling and stratigraphic studies.
Description
Fumarole Butte lies north of the Sevier Desert. It is located in the scoria-rich valley of a basaltic lava field, on top of Tertiary-aged structures of rhyolitic lava. Made of red and gray material, its composition ranges from dark basalt to reddish scoria.
Fumarole Butte formed during the Jaramillo normal event, approximately one million years ago. It is a shield volcano with a volcanic neck protruding from the center. On the edges of the volcano, lacustrine deposits can be found where the volcano was once covered by Lake Bonneville.
Crater Bench Formation
Eruptions from Fumarole Butte created the basaltic Crater Bench Formation, which lies beneath the neck. It is around 900,000 years of age, dated to the Pleistocene. The area is divided by faults and ranges in thickness from 6 meters (20 ft) to 180 meters (591 ft). The primary component of the lava is aphyric basaltic andesite in which tiny crystalline structures are visible.
References
- ^ U.S. Geological Survey Geographic Names Information System: Fumarole Butte
- ^ Topinka, Lyn (11 Jun 2003). "America's Volcanic Past: Utah". vulcan.wr.usgs.gov. United States Geological Survey. Archived from the original on 19 June 2010. Retrieved 12 Nov 2010 – via Wayback Machine.
- ^ "Lake Bonneville's cycles: Climate clues". Science News. 108 (19): 296. November 8, 1975. doi:10.2307/3960485.
- ^ Gilbert, Karl Grove (1890). Lake Bonneville. United States Geological Survey. p. 332. Retrieved 17 Mar 2020 – via Internet Archive.
- ^ Hecker, Suzanne (1993). Quaternary tectonics of Utah with emphasis on earthquake-hazard characterization. Salt Lake City: Utah Geological Survey. p. 21.
- ^ Hintze, Lehi F.; David, Fitzhugh D.; Utah Geological Survey (2003). Geology of Millard County, Utah. Salt Lake City: Utah Geological Survey. p. 168.
External links
- "Fumarole Butte". Global Volcanism Program. Smithsonian Institution. Retrieved 2021-06-28.