Iceland is a young country from a geological viewpoint or around 20-35 million years old. The buildup of the counry has taken place during the latter part of the Cenozoic. Iceland´s crust is almost entirely made of lava flows with sedimentary layers in between. The lava flows have piled up during volcanic eruptions as Iceland is located on a so-called hot spot with a mantle plume where volcanic eruptions take place every 4 years on average.
The geological formations of Iceland can be divided roughly into four parts. The oldest is the dark basaltic formation from late Tertiary. This formation is located on the most western parts of the Westfjords and the most eastern part of the Eastern fjords. Next in line comes the grey basalt formation which was formed during the former part of the last Ice Age. Then comes the hyaloclastite formation which was formed during the latter part of the last Ice Age.
These three formations constitute, to a large extent, the crustal rock formation of the country. On top of the solid rock, the fourth and youngest formation can be found. It mainly constitutes loose sediments such as riverbeds, volcanic soils, ash and young lavas.
Ingibjörg Elsa Björnsdóttir „Landslagið“, Náttúran.is: June 26, 2007 URL: http://natturan.is/d/2007/06/26/landslagi/ [Skoðað:Feb. 22, 2020]Efni má nota eða vitna í samkvæmt almennum venjum sé heimilda getið með slóð eða fullri tilvitnun hér að ofan.
breytt: May 20, 2014