Above is the famous geyser, Old Faithful. Also you see here “mud holes,” the Opal Pool and the Grand Prismatic Spring. Near the bottom, there are a couple photos of how the landscape in general is percolating due to magma very close to the surface. Sometimes the steam makes visibility difficult!
The yellow, orange and brown colors lining the runoff channels are caused by thermophiles, which are heat loving organisms. These microbes contain colorful pigments that allow them to make energy from the sunlight and thrive in the harsh conditions of water heated to 160 degrees F. The largest of these pools measures 200 feet across. I loved the spectrum!