Geysir and Strokkur
Southland, Iceland
Earth's Natural Wonders in Europe & Middle East
Height of Geysir eruptions: 200 feet (60 m)
Height of Strokkur eruptions: 100 feet (30 m)
Frequency of Strokkur eruptions: every 10 minutes	Strokkur geyser in Iceland[1]

 

Geysir (sometimes known as The Great Geysir), in the Haukadalur valley, Iceland, is the oldest known geyser and one of the world's most impressive examples of the phenomenon. The English word geyser to describe a spouting hot spring derives from Geysir (which itself is derived from the Icelandic verb gjósa meaning to erupt. The English verb gush is probably related to that word). Geysir lies on the slopes of Laugarfjall hill , which is also the home to Strokkur geyser about 400 metres south. [4]

Geysir at rest [2]

 

In a geothermal valley of more than 50 hot springs and multicolored mudpots in southwest Iceland are two geysers, which are called Geysir and Strokkur. Geysir was first recognized in 1294, after an earthquake hit the area during the devastating eruption of Mount Hekla. This seismic activity created a number of hot new springs, as well as those two impressive geysers. Geysir's smaller neighbor Strokkur geyser, meaning "the churn," gives a show every ten minutes blasting boiling water 65 to 100 feet in the air. [3]

The oldest accounts of a geyser at Haukadalur date back to 1294. Earthquakes in the area caused significant changes in local neighbouring landscape creating several new hot springs. Changes in the activity of the Geysir and the surrounding geysers are strongly related to earthquake activity. In records dated 1630 the geysers erupted so violently that the valley around them trembled.

In recent times earthquakes have tended to revive the activity of Geysir which then subsides again in the following years. Before 1896, Geysir was almost dormant before an earthquake that year caused eruptions to begin again, occurring several times a day, lasting up to an hour and causing spouts of up to 60 metres in height. In 1910, it was active every 30 minutes; five years later the time between the eruptions was as much as six hours, and in 1916, the eruptions all but ceased. In 1935 a manmade channel was dug through the silica rim around the edge of the geyser vent. This ditch caused a lowering of the water table and a revival in activity. Gradually this channel too clogged with silica and eruptions again became rare. In 1981 the ditch was cleared again and eruptions could be stimulated, on special occasions, by the addition of soap. Following environmental concerns the practice of adding soap was seldom employed during the 1990s. During that time Geysir seldom erupted. When it did erupt, it was spectacular, sending boiling water sometimes up to 70 metres into the air. On the Icelandic National Day authorized government geologists would force an eruption. A further earthquake in 2000 revived the geyser again. Initially eruptions were taking place on average eight times a day. By July 2003 this activity had again decreased to around three times per day.

The nearby geyser Strokkur erupts much more frequently than Geysir, erupting to heights of up to 20 metres every five minutes or so. Strokkur's activity has also been affected by earthquakes, although to a lesser extent than the Great Geysir. There are around thirty much smaller geysers and hot pools in the area, including one called Litli Geysir ('Little Geysir').[3]

Litli Geysir, Haukadalur, IcelandDescriptions of the Great Geysir and Strokkur have been given in every travel guide to Iceland published from the 18th century onwards. Today the geyser remains an essential element of almost every tourist's itinerary. The place is, together with Þingvellir and the Gullfoss waterfall, part of the most famous sights of Iceland, the Golden Circle.[4]