Page "Geysir" Paragraph 7

History of recent centuries shows that 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 became 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 and it reaches 122 meters for two days, thus becoming one the highest known geysers in history ( Waimangu Geyser in New Zealand has been erupting up to 460 m high ).

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.