Daily Earth Science Geosphere Repost

The Icelandic Plume

Imagine a column of molten rock that is over 400 kilometers tall and 100 kilometers wide. Temperatures in the column reach 1,600 degrees Celsius. This molten rock then forms a plume that rises from the depths below us and pushes its liquid core to the surface of the earth.  At the surface, magma from the plume then pours out over the sea bottom, forming a massive plateau of rock rising 3000 meters above the seafloor and covering an area of 350,000 square kilometers. Eventually, the top of this feature extends above sea level, thus creating a massive island covered with volcanoes and bubbling hot springs. This island is Iceland, and the molten rock is the Icelandic Plume.

This plume of molten rock forms the Iceland hotspot. The magma from the plume makes Iceland one of the most volcanically active regions on earth with over 200 volcanos. However, the hotspot is not new. The original formation of the Icelandic Plume is believed to be related to the opening of the North Atlantic about 60 million years ago. But its activity building Iceland occurred over the past 16 – 20 million years. So, island-building is a dynamic process, and in 1963 one of the world’s youngest islands (Surtsey) popped up off the coast of Iceland in a series of volcanic eruptions. Geology in action is the only way to describe this event.

The big picture

Iceland is part of the Mid-Atlantic Ridge that separates the Eurasian and North American tectonic plates. The rift between the two plates runs through the middle of Iceland, causing east Iceland and west Iceland to move apart at a rate of 2.5 centimeters (1 inch) per year. So, you can visit the Thingvellir valley and straddle the plate boundary with one foot in Europe and the other in North America.

Other hotspots around the world, like the one under Hawaii, produce large islands, but if you look at a map, you will see a distinct difference between the relatively smooth edges of the Hawaiian Islands and the jagged edges of Iceland. The coastline of Iceland reflects glacial action during the last ice. Fjords that incise the coast separate the fingerlike promontories giving a rugged look to the Iceland map. 

Sustainable Energy

Massive glaciers formed over Iceland during the last ice age, and they carved out large valleys that turn into fjords as they pass from land to sea. Some of these glaciers remain even today. The largest one, Vatnajokull, is located on the SE side of the island. The water resources encompassed by these glaciers also provide massive amounts of hydroelectric power to the country. So, about 73% of the electric power for the country is generated via waterpower. 

Iceland runs on almost 100% sustainable energy. The hot, fiery reservoirs of magma beneath the island also provide power in the form of geothermal energy. About 27% of Iceland’s electricity comes from geothermal generation, and geothermal energy heats 85% of all the homes in the country. Therefore, the Icelandic Plume that created the island also serves as a modern-day natural resource, enhancing the lives of those who live there.

Iceland is a stunning example of the intersection between geology, hydrology, technology, and civilization. The combination of volcanic heat below the surface and polar glaciers above confirms Iceland’s status as the land of “ice and fire.”


The Axial Seamount: a very active volcano (Source: ArcheanWeb) – https://archeanweb.com/2020/03/20/the-axial-seamount-a-very-active-volcano/ Also:

Yellowstone National Park, part of a living earth (Source: ArcheanWeb) – https://archeanweb.com/2020/03/26/yellowstone-national-park-part-of-a-living-earth/ Also:


Origin of the Iceland hotspot and the North Atlantic Igneous Province: http://www.mantleplumes.org/WebpagePDFs/Iceland3.pdf Also:

ICELAND IS A LEADER IN RENEWABLE ENERGY (Source: InspiredByIceland) – http://inspiredbyiceland.com/article/renewable-energy Also:

VATNAJÖKULL (Source: InspiredByIceland) – http://inspiredbyiceland.com/article/vatnajokull Also:

Feature Image: Brennisteinsalda volcano at Landmannalaugar in Iceland (By: Mélissa) (Modified) –  https://commons.wikimedia.org/wiki/File:Brennisteinsalda_volcano_at_Landmannalaugar_in_Iceland.jpg  – This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. –  https://creativecommons.org/licenses/by-sa/3.0/deed.en

William House
William is an earth scientist and writer with an interest in providing the science "backstory" for breaking environmental, earth science, and climate change news.