Unnamed hydrothermal features in the Rainbow Pool area @jsj1771

Uploaded January 2026 | Updated September 2026, 2 weeks ago

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Unnamed hydrothermal features in & near Rainbow Pool

Geysers are hot springs that episodically erupt columns of water. They occur in few places on Earth. The highest concentration of geysers anywhere is at the Yellowstone Hotspot Volcano in northwestern Wyoming, USA.

Rainbow Pool is a large hot spring in the Black Sand Basin of Yellowstone’s Upper Geyser Basin. From 2013 to 2017, overflow ran off to the south and southeast toward Iron Spring Creek. From 2020 to 2025 (at least), some overflow has drained to the west and southwest, eventually percolating downward into weathered gravel. This video shows an unnamed active spouter in the southwestern part of Rainbow Pool, plus some small active features in the mouth of a southwestward-draining Rainbow Pool runoff channel & between Rainbow Pool and the boardwalk. 38 active features were observed in this area on 5 August 2025. Activity ranged from perpetual spouting to low splashing to slight bubbling.

Black Sand Basin videos:
youtube.com/playlist?list=PL8dL6UmmXTBVwmCwqDQXjddb1pn82Whbf

All clips - Unnamed hydrothermal features in & around Rainbow Pool in the late afternoon of 5 August 2025.

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Unnamed hydrothermal features in the Rainbow Pool area

$Seismic Geyser (2021) (HD) Seismic Geyser (2021) Geysers are hot springs that episodically erupt columns of water. They occur in few places on Earth. The highest concentration of geysers anywhere is at the Yellowstone Hotspot Volcano in northwestern Wyoming, USA. Seismic Geyser is located in the northwestern Cascade Group of Yellowstone’s Upper Geyser Basin. Its earliest manifestation appeared in August 1959, when the half minute-long Hebgen Lake Earthquake (R = 7.3 to 7.5) struck the Yellowstone area. The quake significantly affected Yellowstone’s hydrothermal features. In the Cascade Group, two new fractures appeared in the siliceous sinter buildup on the eastern side of the Firehole River, about 40 meters south of the pre-existing Hillside Geyser. Both were oriented subparallel to the river (striking near-north); the western fracture was in the steep river embankment and the eastern fracture was in the flats above it, in a lodgepole pine forest next to a very old wagon road. The ground heated up and killed a section of the conifer forest. Both fractures became energetic fumaroles (steam vents). The fumaroles were active from 1959 to late 1962 or early 1963. During the 1962-1963 winter, one or more explosive events enlarged the eastern fracture into a crater, surrounded by siliceous sinter rubble. The crater acted as a geyser from 1963-onward and the western fracture gradually ceased fumarolic activity. The new geyser was eventually called “Seismic Geyser”. The energy of its geyser eruptions increased in the mid-1960s and the crater also changed shape, due to explosive activity. Eruptive bursts reached up to ~15 to 20 meters high. In early 1971, another geyser appeared on the southeastern side of Seismic Geyser - it became known as Seismic’s Satellite Geyser. Initially, they erupted together, but Seismic’s activity decreased and geyser eruptions eventually occurred only at Seismic’s Satellite. The last known sizable Seismic eruption was in 1974; smaller eruptions were reported in summer 1997. Seismic’s Satellite has been mostly quiet since the 1980s. Modern activity at Seismic Geyser consists of boiling and heavy overflow events every half-hour or so. Mostly synthesized from: Marler & White (1975) - Seismic Geyser and its bearing on the origin and evolution of geysers and hot springs of Yellowstone National Park. Geological Society of America Bulletin 86: 749-759. Bryan (2008) - The Geysers of Yellowstone, Fourth Edition. 462 pp. Filmed from the Daisy Trail. Still photos 1-5 - Seismic Geyser erupting in 1965, 1967, 1969, and 1970 (public domain photos provided by the American National Park Service). Clips 1-14 - Seismic Geyser in the early evening of 29 May 2021.$

Fountain Geyser (4:16-4:42 PM, 8 August 2025)