GIBBON
GEYSER BASIN (YELLOWSTONE
HOTSPOT) HYDROTHERMAL FEATURES
Gibbon Geyser Basin consists of nine
scattered hydrothermal areas in and around the Gibbon Meadows and northern
Gibbon Canyon areas of Yellowstone Park.
Beryl Spring (above & below), western side of
Gibbon River Canyon, southern Gibbon Geyser Basin, Yellowstone Hotspot,
northwestern Wyoming, USA.
Beryl Spring is a boiling-hot, overflowing
hot spring that has only erupted after the 1959 Hebgen Lake Earthquake. Its pool has transparent, bluish water
reminiscent of aquamarine, a gem-variety of the mineral beryl. Immediately uphill & west of Beryl Spring
is a fumarole (steam vent).
Above: July 2012 (looking ~NW).
Below: August 2010 (looking ~SW).
Beryl Spring (above & below) in July 2012.
Beryl Spring (above & below) in August 2010.
Beryl Spring in August 2010 (above) and July 2012
(below).
Beryl Spring is surrounded by geyserite (siliceous
sinter), a chemical sedimentary rock composed of opal (SiO2·nH2O). The silica in geyserite is precipitated from
the spring’s hot water. The dissolved
silica in the water is ultimately derived from hydrothermal leaching of
late-Cenozoic aged rhyolites in the subsurface.
(August 2010)
Beryl Spring’s outflow channel, walled by geyserite
(siliceous sinter). (August 2010)
Paintpot Hill (above & below), southeast-central
Gibbon Geyser Basin, Yellowstone Hotspot, northwestern Wyoming, USA in August
2011. Above: looking ~S. Below: looking ~NW.
Paintpot Hill is located just north of
Yellowstone’s 640 ka caldera. The hill
is one of several rhyolite domes of varying ages in the Obsidian Creek Member
of the Plateau Rhyolite (upper Middle Pleistocene). Zircons from Paintpot Hill rhyolite have ages
of 205 to 225 ka. Rhyolitic obsidian
from the summit of Paintpot Hill gives dates of 171 and 183 ka.
The active and recently-active
hydrothermal areas on the northern slope of Paintpot Hill and on the flats
adjacent to the northern base of the hill are pastel- to
intensely-multicolored, giving rise to the name. Geysers, perpetual spouters, fumaroles,
sizzlers, bubbling mud pools, and mud pots are present at Paintpot Hill.
“Dog Bone Pool” (above &
below), just north of Paintpot Hill, Artists’ Paintpots Group,
southeast-central Gibbon Geyser Basin, Yellowstone National Park, northwestern
Wyoming, USA in August 2011.
This pool is unnamed, but its shape
inspired the name “Dog Bone Pool” with at least one Yellowstone geyser
gazer. The multicolored ground
surrounding “Dog Bone Pool” is weathered and altered rhyolite and geyserite,
stained pinkish, orangish, and reddish by iron oxides (principally hematite).
Blood Geyser (above & below), northern base of
Paintpot Hill, Artists’ Paintpots Group, southeast-central Gibbon Geyser Basin,
Yellowstone Hotspot, northwestern Wyoming, USA.
Above: July 2012. Below: August 2011.
Blood Geyser is a perpetual spouter at the
base of Paintpot Hill. Water eruptions
here are low, but can reach up to 6 feet high.
Blood Geyser is surrounded by rubble and hematite (reddish) &
limonite (yellowish) stained geyserite.
The staining comes from precipitation of iron oxides directly from the
erupted water as it cools.
Blood Geyser in August 2011.
Flash Spring (above & below), base of Paintpot
Hill, Artists’ Paintpots Group, southeast-central Gibbon Geyser Basin,
Yellowstone Hotspot, northwestern Wyoming, USA.
Above: July 2012. Below: August 2011.
Flash Spring’s behavior is similar to that
of Firehole Spring in the Lower Geyser Basin.
Activity here consists of the flame-like appearance of gas bubbles from
the vent at the bottom of the pool. Many
of the bubbles immediately cool and condense and only minimally disturb the
pool’s surface. Other bubble masses
result in small splashing bursts. Flash
Spring’s vent is reported to emit gas bubbles dominated by carbon dioxide (CO2).
Flash Spring in August 2011.
Hematite-rich pools, base of Paintpot Hills, Artists’
Paintpots Group, southeast-central Gibbon Geyser Basin, Yellowstone Hotspot,
northwestern Wyoming, USA in August 2011.
The water erupted at nearby Blood Geyser
(see above) has a relatively high dissolved iron oxide content. The small pools and channels shown above also
have water that is precipitating reddish hematite (Fe2O3)
and yellowish limonite (FeO·OH·nH2O).
Hot spring pools on the northern slopes of Paintpot Hill,
Artists’ Paintpots Group, southeast-central Gibbon Geyser Basin, Yellowstone
Hotspot, northwestern Wyoming, USA in August 2011.
Mud cones (above & below), northern slopes of
Paintpot Hill, Artists’ Paintpots Group, southeast-central Gibbon Geyser Basin,
Yellowstone Hotspot, northwestern Wyoming, USA in July 2012.
The yellowish material encrusting the
dried mud appears to be elemental sulfur.
Mud pits and mud cone on the northern slopes of Painpot
Hill. (July 2012)
Artists’ Paintpots (above & below), Artists’ Paintpots
Group, southeast-central Gibbon Geyser Basin, Yellowstone Hotspot, northwestern
Wyoming, USA in August 2011 and July 2012.
This site is one of my top favorite
geology localities. Artists’ Paintpots
on Yellowstone’s Paintpot Hill are a classic example of mud pots. Mud pots are scarce hydrothermal features
where gases rise through “mud” - viscous slurries of fine-grained sediments and
water. From boreal spring to boreal
summer, the viscosity of the mud pots increases. Gases reaching the top surface energetically
push hot blobs of mud into the air, sometimes up to 20 feet high.
The mud itself is the result of chemical
weathering and breakdown by hot, acidic groundwater of Paintpot Hill Dome
rhyolite (205-225 ka, upper Middle Pleistocene).
Artists’ Paintpots (above & below)
Artists’ Paintpots (above & below)
Artists’ Paintpots (above & below)
Artists’ Paintpots (above & below)
Artists’ Paintpots (above) - irregularly pustlose surface of
friable, dried mud surrounding active crater of mud pots. Each nodule is a dried blob of mud that was
spit from the central crater area.
Artists’ Paintpots (above & below) - active mud pot on
Paintpot Hill.
Artists’ Paintpots (above & below) - active mud pot on
Paintpot Hill.
Artists’ Paintpots (above & below) - active mud pot on
Paintpot Hill.
Artists’ Paintpots (above) - active mud pot on Paintpot
Hill.
Info. mostly synthesized from:
Bindeman, I.N. & J.W. Valley. 2001. Low-δ18O
rhyolite from Yellowstone: magmatic evolution based on analyses of zircons and
individual phenocrysts. Journal of Petrology 42: 1491-1517.
Bryan, T.S. 2008. The Geysers of Yellowstone, Fourth Edition. Boulder, Colorado. University Press of Colorado. 462 pp.
Christiansen, R.L. 2001.
The Quaternary and Pliocene Yellowstone Plateau Volcanic Field of
Wyoming, Idaho, and Montana. United States Geological Survey Professional
Paper 729-G. 145 pp. 3 pls.
Christiansen, R.L. & H.R. Blank. 1972.
Volcanic stratigraphy of the Quaternary Rhyolite Plateau in Yellowstone
National Park. United States Geological Survey Professional Paper 729-B. 18 pp.
Fritz, W.J. 1985. Roadside Geology of the Yellowstone Country. Missoula, Montana. Mountain Press Publishing Company. 149 pp.
Schreier, C. 1987. A Field Guide to Yellowstone’s Geysers, Hot
Springs and Fumaroles. Moose,
Wyoming. Homestead Publishing. 96 pp.
Spell, T.L. 2004.
Ion microprobe 206Pb/238U and 230Th/238U
zircon ages from extracaldera rhyolites at Yellowstone: constraints on magma
residence times and evolution. Geological Society of America Abstracts with
Programs 36(5): 431.