Mammoth Hot Springs, Yellowstone National Park, chunks of calcium carbonate sticking out

 Mammoth Hot Springs is sometimes called a mountain turning itself inside out. Hot water deep underground dissolves calcium where it combines with carbon dioxide to make calcium carbonate. Once that solution comes to the surface, the water evaporates and the remaining water cools, resulting in the mineral being deposited into flowing shapes. Calcium carbonate is also the mineral that cave features like stalagmites and stalactites are made of and the white powdery substance you can see in your kitchen sink.

In this photo, you can see some of the flowing shapes have broken off and are lying across the terraces at odd angles. One of the chunks at the upper left appears to be almost completely upside down, with "fingers" of calcium carbonate sticking up. The colors in the white calcium carbonate come from bacteria and algae growing in the warm water. A reddish tinge can also be a sign that iron is mixed in. We were on a boardwalk that leads down from the top of a hill to get in position for this shot. f/8, 1/800 sec, 55 mm, Canon Powershot SX530 HS.

Remember, it's not just a picture, it's a story!

Yellowstone's Mammoth Hot Springs with hot water spilling over the edge of the terrace

View of Mammoth Hot Springs in Yellowstone National Park from the trail with hot water flowing from underground and spilling over the edge of a terrace that's constantly building up from the minerals, calcium carbonate, the water deposits. Steam rises from the water as it emerges from underground. The minerals form where the stream of water drips down, leaving an "icicle" of minerals. A couple of the chunks of mineral having broken off in the past and you can see the "icicles" point upward near the left-center of the screen. Another chunk is lying on its side with orange bacterial growth at the center.

This feature is in a state constant, gradual change and can engulf trees, and even parts of the terrace that are older, or the flow can shift and leave a section of the terrace dry and subject to erosion. This picture was taken with an ISO of 100, f/8, and 1/800 sec. The shutter speed helped to capture the drops of water spilling over the edge of the upper terrace.

Remember, it's not just a picture, it's a story!

Minerva Terrace in Yellowstone NP, at Mammoth Hot Springs

Minerva Terrace is located at Mammoth Hot Springs, at the northern end of Yellowstone National Park.  This photo was taken in the mid-1980s and these terraces have changed over time so they no longer look like this.  Over the years, shifting water flows can cause some terraces to dry out and crumble and new terraces to form elsewhere.  This view is looking northward toward the Gardiner River Canyon where storm clouds threatened rain.

 This picture, taken during a previous trip, shows the terrace engulfing trees that used to grow on this hillside and are now dead and nearly buried.

This image, taken on the same trip as the one above, shows a sign placed on the terrace by the Park Service being gradually covered over by the minerals of the hot spring.

March 1st is Yellowstone National Park's anniversary.

Happy 144th Birthday Yellowstone!

Remember, it's not just a picture, it's a story.