2014-11-20

Silfra Crack | The rift between two Continents

The Silfra crack or fissure is a rift that is part of a divergent tectonic boundary located between the North American and Eurasian tectonic plates. Diving down the Silfra crack allows divers to be able to swim between continents and actually touch two tectonic plates at the same time. These two tectonic plates drift apart roughly 2cm per year. The Silfra crack is located at the rim of Þingvallavatn Lake located within the Thingvellir (Þingvellir) National Park, South Iceland.

Image credit Frank Schäfer

Thingvellir National Park is recognized as a UNESCO WOLRD HERITAGE SITE for its cultural and historical significance as well as natural and geological uniqueness (a feature that we are quite fond of here at UTF). Þingvallavatn Lake is the largest natural lake in Iceland at 114m or 374ft at its greatest depth. The Silfra crack is the only place where one can dive or snorkel directly between two continental plates. The lake has a reputation as the “clearest waters on Earth” allowing for amazing visibility. The water collects as glacier melt from the Langjökull Glacier, the second largest ice cap in Iceland, roughly 20 miles away. The waters remain cold in temperatures all year round between -4°C – 2°C or 24°F – 35°F. Although trout fishing is popular here along with an abundance of other fish species, the fish usually do not venture far into the Silfra crack. The marine life in the Silfra consists of mostly “bright green “troll hair” and different types of algae that provide a “colorscape” unlike anything that occurs naturally above the surface” (Dive.IS). Some divers describe the experience as a feeling of flight and weightlessness and “as close to a space walk as one can get without being in space”. source