In the northern part of Iceland, far from the coastline, the lava plains stretch around Lake Myvatn. Quite and blue, the lake marks an unexpected contrast in the middle of Krafla‘s lava fields and hot springs. Krafla is among Iceland’s most active volcanoes and has a 10-kilometre wide caldera. Between 1724 and 1729, during a volcanic paroxysm phase known as “Myvatn Fire”, the volcano caused a fissure over 90 kilometres long, 10 kilometres wide and 2 kilometres deep.
These fissures are deep cracks in the earth crust provoked by the ajar movement of two tectonic plates. For some time – centuries, but that’s just a blink of an eye in geological therms – this movement deforms the earth crust, until a breach opens and the magma rises on the surface, creating a flood basalt.
Myvatn is an eutrophic lake: its waters are rich of nutrients, phosphates are double as much as in average lakes, but the eutrophic condition may produce negative consequences over the whole ecosystem. For example, the strong concentration of nutrients may lead to an excessive growth of seaweeds, which feed on oxygen and may cause oxygen-free water coves. The paradox is that too many nutrients remove the life inhabiting the lake.
On the other side there is plenty of oxygen in the air, where birds and insects live, especially mosquitos! After all, Myvatn means “insect lake”.
The lake and the swamps surrounding it are a green and blue oasis in the middle of brown lava fields. Myvatn is there from time immemorial, but it has not always been like that. The previous water pound has been swallowed by lava and the picturesque rock formations all over the shore are small craters originated by the contact of water and lava.
Climbing from the lake towards Krafla’s peak, you can meet with Kröflustöd geothermal station, which uses eleven hot springs and generates up to 60 Megawatt. The road ends with Viti, the “hell’s crater”. Viti’s diameter is 320 metres and it dates back to 1724, at the beginning of Myvatn Fire age. Now it’s extinguished and filled with water, and the hellish landscape left room to an harmonic view of water and colours.