The Geysir geothermal area in Iceland is a natural wonder, drawing visitors worldwide. This landscape, sculpted by geothermal forces, displays the Earth’s power. The region features steaming vents, bubbling hot springs, and erupting geysers.
The Famous Geysir Versus Its Active Neighbor
Many visitors to the geothermal field in Iceland seek to witness an eruption from “Geysir” itself, often referring to the entire area. However, visitors should distinguish between the Great Geysir, which lent its name to all other geysers worldwide, and Strokkur, its highly active neighbor. While the entire Haukadalur valley is known for its geothermal activity, the Great Geysir erupts very infrequently today.
Strokkur, located just a short distance from the Great Geysir, is the main attraction for those wishing to see regular eruptions. It provides a consistent and powerful display of superheated water and steam. This distinction helps visitors manage expectations about what they will experience at this site.
Geysir’s Eruption History and Current Status
The Great Geysir has a long and varied history of activity, marked by periods of intense eruptions and extended dormancy. Historical accounts suggest it became active around 1150 CE, with early descriptions noting its power. Before 1896, the Great Geysir was largely dormant, but an earthquake that year revived its activity, causing it to erupt multiple times a day, sometimes reaching heights of 70 to 80 meters.
Its activity began to decline again in the early 20th century, becoming almost entirely dormant by 1916. While human intervention, such as digging channels and adding soap, temporarily stimulated eruptions in the past, these practices are now discouraged due to environmental concerns. Earthquakes have historically triggered Geysir’s reawakening, with the most recent major revival occurring after seismic activity in 2000. However, large eruptions of the Great Geysir have become very rare, with a notable event occurring in 2016 due to its infrequency.
Factors Affecting Geysir’s Activity
The behavior of geysers like the Great Geysir is linked to geological processes beneath the Earth’s surface. Geysers require a combination of heat, water, and an underground plumbing system with constrictions. In Iceland, the heat source comes from magma close to the surface, as the island sits on the Mid-Atlantic Ridge where tectonic plates are moving apart. Groundwater seeps down through cracks and fissures, where it contacts these hot rocks and becomes superheated.
Pressure builds within these conduits until the superheated water and steam are forcefully ejected. Changes in seismic activity can impact a geyser’s plumbing system by altering underground channels, either opening them to increase activity or closing them to induce dormancy. Historically, human interventions, like clearing the silica rim or adding soap, temporarily affected eruption frequency by altering water levels or surface tension within the geyser’s vent.
The Eruptions You Will Likely See
For visitors to the Geysir geothermal area, the most reliable eruptions come from Strokkur. This geyser is known for its consistent activity, typically erupting every 5 to 10 minutes. Strokkur’s powerful bursts can send columns of boiling water and steam to heights ranging from 15 to 40 meters (approximately 49 to 131 feet).
This frequent and predictable display makes Strokkur a highlight, ensuring most observers will witness its spectacle. While the Great Geysir remains a historical icon, its current dormant state means seeing it erupt is an exceptionally rare occurrence.