What is Geyser?

A geyser is a vent in Earth's surface that periodically ejects a column of hot water and steam. Even a small geyser is an amazing phenomenon; however some geysers have eruptions that blast thousands of gallons of boiling hot water up to a few hundred feet in the air.

Old Faithful is the world's best known geyser. It is located in Yellowstone National Park (USA). Old Faithful erupts every 60 to 90 minutes and blasts a few thousand gallons of boiling hot water between 100 and 200 feet into the air.

Conditions Required for a Geyser

Geysers are extremely rare features. They occur only where there is a coincidence of unusual conditions. Worldwide there are only about 1000 geysers and most of those are located in Yellowstone National Park (USA).

Conditions Required for Geysers

1) hot rocks below

2) an ample ground water source

3) a subsurface water reservoir

4) fissures to deliver water to the surface

Where are Geysers Found?

Most of the world's geysers occur in just five countries: 1) the United States, 2) Russia, 3) Chile, 4) New Zealand and 5) Iceland. All of these locations are where there is geologically recent volcanic activity and a source of hot rock below.

Countries With Many Active Geysers

1) United States - Yellowstone National Park

2) Russia - Dolina Geiserov

3) Chile - El Tatio

4) New Zealand - Taupo Volcanic Zone

5) Iceland - Many locations

How Often Do Geysers Erupt?

Most geysers erupt irregularly and infrequently. However, a few are known for regular eruptions. The most famous, named "Old Faithful" in recognition of its regular eruptions, is located in Yellowstone National Park (USA) and erupts about every 60 to 90 minutes. More details on the eruption intervals of Yellowstone geysers is given in the table below.

Old Faithful is Getting Slower

Research done at the United States Geological Survey suggests that long-term drought conditions in the Yellowstone area have lenghtened the time interval between Old Faithful's eruptions. The delay is thought to be caused by a smaller water supply.

Yellowstone Geysers Eruption Intervals, Duration, Heights
Location	Average Interval	Duration	Height (ft)
Old Faithful	65 or 92 min	1.5-5 min	106-184
Artemisia	irregular	5-25 sec	30
Aurum	2-4 hours	70 sec	20
Baby Daisy	35-55 min	3 min	25
Beehive	12-18 hours	5 min	150+
"Boardwalk"	irregular	5-10 min	20
Castle	12.5 hours	15-20 min	75
Daisy	2.5 hours	3.5 min	75
Depression	5-9 hours	6 min	10
Echinus	irregular	3-5 min	30+
Fan & Mortar	6-10 days?	45 min	100+
Fountain	5.5 hours	9 min	78
Giant	last eruption 12/24/03	1 hour	200+
Giantess	last eruption 4/21/04	4-48 hours	150+
Grand	8.5 hours	8-12 min	160+
Great Fountain	12.5 hours	45 min	70-200+
Lion - initial to intitial	about 8 hours	1-7 min	60
Lion - within series	about 90 min	3-5 min	30
Little Cub	about 55 min	10 min	5
Plate	3.5-4 min	4 min	5
Plume	recent periods of dormancy	1 min	25
Riverside	6.25 hours	20 min	75
Steamboat	last eruptions 4/27/03 and 5/23/05	10+ min	300+
Riverside	6.25 hours	20 min	75
Data from National Park Service (Measurements done in 2002)