In the area around Myvatn there are large, geological cracks in the earth that have formed between the Eurasian and North American tectonic plates.

Nearly 11% of Iceland is covered with glaciers: thick packs of snow are compressed into ice by weight and slowly but surely slide off the mountainside. Icelandic glaciers flow fairly quickly, namely more than 1 meter per day. The large amounts of debris and sharps that have been carried along are best visible on the end (terminal moraine) and on the sides (lateral moraine).