Dusty Jeans & Genes - Part 21 - Yellowstone National Park - Geology (Mostly)

Friday, 4 May 2018

We're spending two days in Yellowstone National Park. Today is "geology day"; tomorrow is "wildlife day".

It might be "geology day", but this is Yellowstone. Even before getting to any thermal features, we couldn't avoid wildlife!

Although you can't see it in the first photo, a young calf was following its mother on the road. Bison calves can walk and follow the herd within an hour of birth.

Even though I've seen Old Faithful erupt a number of times, it never fails to impress. While fairly tall, Old Faithful is not the tallest geyser, but it is the tallest regularly erupting geyser (about every 70 minutes).

Grand Prismatic Spring in the Midway Geyser Basin. You're really too close to get the full effect of the colors. The colors in Yellowstone are due to bacteria in the water. Different bacteria tolerate different temperatures, so you can tell the temperature of the water from the color of the bacteria.

It's that pesky wildlife interfering with geology again. The bacterial mats around the hot pools are easily (and permanently) marred by scrapes - intentional or otherwise. Here passing bison left tracks.

It doesn't take the mass of a bison to leave a track in a bacterial mat. These are wolf tracks.

Silex Spring in the Lower Geyser Basin. The dark blue center shows that the water is too hot for bacteria to grow.

Fountain Paint Pots. Paint pots are made when hot gases and steam bubble up through thick mud.

Spatter cones next to the paint pots, where the mud has dried to a near-solid consistency.

Nearby is Red Spouter that flings red mud around. The red is due to arsenic (not iron) in the mud (but I can't find any confirmation of that online).

Spasm Geyser erupts continuously in the Lower Geyser Basin.

Wildlife sign again. We had to ask a ranger to identify these strange structures on top of the ground. They are pocket gopher "eskers". During the winter, pocket gophers excavate burrows and fill snow tunnels with the mud. After the snow melts, the mud remains, similar to the way eskers form in glaciers.

The "Golden Gate" pass from the Mammoth area to the interior of the park. In horse-drawn coaches over a timber trestle it much have been quite a challenge. Even today it's intimidating.

At the top of Golden Gate canyon, Glen Creek flows over Rustic Falls, swollen by spring melt water.

And to complete the day, we had a magnificent rainbow as we approached Mammoth Hot Springs.