West Thumb Geyser Basin, Yellowstone National Park: West Thumb Geyser Basin stands out because it is on the edge of, and partially submerged by, Yellowstone Lake, which creates a dramatic backdrop for the dynamic geysers, pools, and springs.
Punch Bowl Spring, Yellowstone National Park: Punchbowl Spring is an accurately-named spring at Yellowstone. It is about 3.5 meters in diameter and is contained by a "punch bowl" of scalloped sinter about 1 meter high. The spring is deceptively deep (more than 6 meters) and constantly boils away as seen in this image, with water running off through several channels
Travertine Terrace, Mammoth Hot Springs, Yellowstone National Park: At Mammoth Hot Springs water rises through the limestone, carrying high amounts of dissolved calcium carbonate. At the surface, carbon dioxide is released and calcium carbonate is deposited, forming travertine, the chalky white rock of the terraces
Upper River Basin, Morning Glory Pool, Yellowstone National Park: Morning Glory Pool was named by the wife of an Assistant Park Superintendent, in 1883, after she called it "Convolutus", the Latin name for the morning glory flower, which the spring resembles. By 1889, the name Morning Glory Pool had become common usage in the park
Castle Geyser, Yellowstone National Park: Castle Geyser is a cone geyser in the Upper Geyser Basin. It is noted for the large geyserite sinter deposits, which form its cone. These deposits have been likened in appearance to a castle. It has a 10 to 12 hour eruption cycle. The geyser erupts hot water for about 20 minutes in a vertical column that reaches a height of 90 feet (27 m) before changing to a noisy steam phase that issues for 30 to 40 minutes.
Old Faithful, Yellowstone National Park: Old Faithful was named by the first official expedition to Yellowstone, the Washburn Expedition of 1870. They were impressed by its size and frequency. The eruption heights vary from 106 feet to 184 feet, with an average of 130 feet, and discharges of up to 8,400 gallons of water per eruption.
Norris Geyser Basin, Yellowstone National Park: The Norris Geyser Basin is the hottest, oldest, and most dynamic of Yellowstone's thermal areas. The highest temperature yet recorded in any geothermal area in Yellowstone was measured in a scientific drill hole at Norris: 459°F (237°C) just 1,087 feet (326 meters) below the surface.
Upper River Basin, Morning Glory Pool, Yellowstone National Park: The distinct color of the 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.
Daisy Geyser, Yellowstone National Park: An eruption of Daisy Geyser starts with boiling water splashing from one of several vents in the thick sinter ledge partially surrounding the geyser’s crater. This eruption indicator means that a full eruption is about to occur. Boiling water soon pours over the crater’s edge, and the splashing increases until the eruption starts.
Anemone Geyser, Yellowstone National Park: The Anemone Geyser is actually two related geyers in the Upper Geyser Basin of Yellowstone National Park, The larger of the two is known as Big or North Anemone while the smaller is known as Little or South Anemone. The two geysers were named after the anemone flower by the Hague Party in 1904.
Grand Geyser, Yellowstone National Park: Grand's fountain reaches a height of as much as 200 feet (61 m), with a duration of 9 to 12 minutes. Its eruptions normally occur in a series of 1 to 4 bursts. The forecasted window of opportunity for an eruption of Grand Geyser is four hours which means that patience is required.
Daisy Geyser, Yellowstone National Park: Daisy Geyser is part of the Daisy Group. It was named prior to 1890 by the Hague Party. It erupts every 110 to 240 minutes for a period of 3 to 5 minutes and is one of the most predictable geysers in the park. Its fountain erupts at an angle to the ground and reaches a height of 75 feet (23 m).
Grand Geyser, Yellowstone National Park: The Grand Geyser, which erupts every 7 to 15 hours, belongs to the Grand Group (or Grand Geyser Complex), and its eruption is connected to those of the other geysers in the group, especially the adjacent Vent Geyser and Turban Geyser.
Liberty Cap, Mammoth Hot Springs, Yellowstone National Park: Estimated to be 2,500 years old the 12 meter high Liberty Cap, which was created by a hot spring that was active in one location for a long time. Its internal pressure was sufficient to raise the water to a great height, allowing mineral deposits to build slowly and continuously for perhaps hundreds of years.
West Thumb Geyser Basin, Blue Funnel Spring: Blue Funnel Spring is one of the larger pools and one of the most striking because of its circular rim and pastel blue color which intensifies as the pool deepens towards its central vent. The hottest pools are the bluest since colorful cyanobacteria that live in cooler springs change the color of those springs.