Hot Spring

Defined as “forming when water deep below the Earth’s surface is heated by rocks or other means, and rises to the Earth’s surface,” or “when rain water flows into the ground and is heated by the radioactive decay of elements present in the rocks and soils that it flows through” [1].

Hot springs differ from many other waterbodies with their extreme water temperatures. The National Park Services (NPS) says that hot spring water temperature averages at “143 degrees Fahrenheit,” with “the temperature of earth’s crust increasing with depth, average—3 to 5 degrees F for every 300 feet down” [2]. However, a more general definition of a hot springs’ temperature has been said to be anything over 98 degrees Fahrenheit [3].

Hot springs also set themselves apart from other waterbodies with their vibrant colors. This color is caused by a “living species called thermophiles. Thermophiles are microorganisms that live in extremely high temperatures, and it is estimated that trillions of thermophiles are grouped together and create the color seen in hot springs." The differences in color, or “color boundaries” within hot springs are due to “specific temperature limits for thermophiles to live in” [2].

References

[1] World of Phenomena. (2020, October 20). Hot Spring. Retrieved (2021, July 21), from http://www.phenomena.org/geological/hotspring/

[2] National Park Service (NPS). (2017, October 26). Hot Springs Retrieved (2021, July 21), from https://www.nps.gov/yell/learn/nature/hot-springs.htm

[3] National Park Service (NPS), (2006). The Natural Systems in Hot Springs National Park or "Follow the Water". Retrieved (2021, July 21), from https://www.nps.gov/hosp/learn/education/upload/followthewater_final.pdf