Grand Geyser

Grand Geyser
File:Yellowstone Grand Geysir 02.jpg Grand Geyser
Name origin	Named during 1871 Hayden Geological Survey
Location	Upper Geyser Basin, Yellowstone National Park, Teton County, Wyoming
Coordinates
Elevation	7,329 feet (2,234 m)
Type	Fountain geyser
Eruption height	200 feet (61 m)
Frequency	7 to 15 hours
Duration	9 to 12 minutes
Southern section of Upper Geyser Basin Southern section of Upper Geyser Basin

Grand Geyser is a fountain geyser in the Upper Geyser Basin of Yellowstone National Park in the United States. It is the tallest predictable geyser known. It was named by Dr. F.V. Hayden in 1871.

Eruptions

Grand's fountain reaches a height of as much as 200 feet (61 m), with a duration of 9 to 12 minutes. Its eruptions occur in a series of 1 to 4 (rarely as many as 5) bursts.

Sequence

Grand erupts every 7 to 15 hours. It 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.

For a few hours before an eruption by Grand, Turban Geyser erupts for a duration of five minutes about every 17 to 22 minutes. Grand's eruption begins within 1 to 2 minutes of the start of one of Turban's eruptions, with Vent Geyser erupting shortly after Grand starts erupting. On occasion, Grand will stop erupting after 7 to 9 minutes, only to restart with a usually taller fountain a minute or two later. Grand has been known to rarely experience over half a dozen restarts in a single eruption period. After Grand ceases its eruption, Vent and Turban can continue to erupt for another hour.

Upon the finish of an eruption, Grand's pool is empty and takes about five hours to refill.

Images of Grand Geyser
Grand Geyser. The small geyser on the left is Vent Geyser Grand Geyser. The small geyser on the left is Vent Geyser  Grand Geyser  Grand Geyser in 2009 Grand Geyser in 2009