Today, let's take a look at the "Morning Glory Pool", a hot spring in the Upper Geyser Basin of Yellowstone National Park in the United States. The odd hot spring was named by Mrs. E. N. McGowan, wife of Assistant Park Superintendent, Charles McGowan in 1883. She called it Convolutus, the latin name for the morning glory flower of which the springs resemble. The distinct color of the Morning Glory Pool is due to bacteria which inhabit the water. On a few rare occasions the Morning Glory Pool has erupted as a geyser, usually following an earthquake or other nearby seismic activity.
Some more pictures below. Plus one nice video in the end.
Also, watch the video on the Morning Glory Pool: