YELLOWSTONE (Day 4 - part 2)

I next stopped at Artist Paint Pots with its 1/3 mile trail.

Mud pots

Terrace Springs, as the name implies, was a couple hot pools on a hill.

Fountain Paint Pots was a 1/2 mile boardwalk loop.

Eruption of Clepsydra Geyser

The Fountain Paint Pot was a pool of bubbling mud. Thermophiles consume some of the gases and convert them into sulfuric acid, which breaks the rhyolite (volcanic rock) down into clay. This mixes with water and forms these mud pots.

Silex Spring

Midway Geyser Basin was home to Yellowstone's largest hot spring... and many other incredible hydrothermal wonders along a 1/2 mile trail.

Map of the basin

The Firehole River... gets lots of hot water flowing into it.

Some very hot ground... with elk prints right in the middle of it!

The Turquoise Pool

The Opal Pool

Approaching Grand Prismatic Spring, Yellowstone's largest spring ... with a sign showing what it looks like from above

Grand Prismatic Spring stretches up to 200 feet across. With a temperature of 160 degrees F, it is often covered with steam. Deep below us, magma from an active volcano heats water that rises to the surface through fissures in the rocks. The result is a hot spring that pours almost 500 gallons of hot water each minute into the Firehole River.

The brilliant blue comes from sunlight being scattered by fine particles suspended in the water. The yellow, orange and brown are from thermophiles.

Minerals dissolved in the hot water are deposited and gradually build the terraced features of the pool.

Excelsior Geyser

Biscuit Basin was a 1/4 mile loop. This thermal basin is particularly volatile, with shifting runoff patterns that kill forests. Its name comes from biscuit-shaped mineral formations.

Firehole River again... and stripes of metal cars, blue river, aqua pools and red earth

Black Diamond Pool

Rivers of color

Sapphire Pool

Mustard Spring... and plants that didn't make it

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