Black Pool

---

title: "Black Pool" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["geothermal-features-of-yellowstone-national-park", "hot-springs-of-wyoming", "geothermal-features-of-teton-county,-wyoming", "hot-springs-of-teton-county,-wyoming"] description: "Hot spring in Yellowstone park, United States" topic_path: "general/geothermal-features-of-yellowstone-national-park" source: "https://en.wikipedia.org/wiki/Black_Pool" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Hot spring in Yellowstone park, United States ::

::data[format=table title="Infobox hot spring"]

Field	Value
name	Black Pool
photo	Black pool.jpg
photo_caption	Black Pool prior to
the 1991 thermophile die-off
location	West Thumb Geyser Basin, Yellowstone National Park, Teton County, Wyoming
coordinates
elevation	7756 ft
hot_spring_type	Hot Spring
temperature	72.9 C
map_image	WestThumbGeyserBasin-BlackPool.jpg
map_caption	West Thumb Geyser Basin
::

| name = Black Pool | photo = Black pool.jpg | photo_width = | photo_caption = Black Pool prior to the 1991 thermophile die-off | name_origin = | location = West Thumb Geyser Basin, Yellowstone National Park, Teton County, Wyoming | coordinates = | elevation = 7756 ft | hot_spring_type = Hot Spring | height = | duration = | frequency = | discharge = | temperature = 72.9 C | depth = | map_image = WestThumbGeyserBasin-BlackPool.jpg | map_caption = West Thumb Geyser Basin | map_width =

Black Pool is a hot spring in the West Thumb Geyser Basin of Yellowstone National Park in the United States.

The pool was cool enough up until 1991 for dark orange-brown cyanobacteria to grow throughout the pool. When combined with the blue of the water, the pool appeared to be an exceptionally dark green to almost black, hence the name.

An exchange of function took place in 1991, shifting thermal energy to Black Pool and nearby Abyss Pool, causing them to heat up. Black Pool's temperature became hot enough to kill all the cyanobacteria in the pool, turning the pool a rich teal blue color. The pool also had frequent boiling eruptions on August 15, 1991, doming the water to 3 feet and causing heavy runoff. Black Pool remains extremely hot, and is now one of Yellowstone's most beautiful and intensely blue pools. The name of the pool remains "Black Pool."

|title=Images of Black Pool |footer= |width=150 |File:Black Pool hot spring in West Thumb Geyser Basin.JPG|Black Pool, 2006 |File:Black Pool and Yellowstone Lake.JPG|Black Pool, 2003 |File:Black Pool in West Thumb Geyser Basin.jpg|Black Pool, 2013

References

References

1. {{cite gnis. 1848501. Black Pool
2. {{cite rcn
3. Scott, Bryan T.. (1995). "The Geysers of Yellowstone". University of Colorado Press.

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::