New Zealand is a great island country, but where would it be without Zealandia propping it up? Zealandia is the submerged microcontinent broken off of the supercontinent Gondwanaland around 80 million years ago that disappeared except for New Zealand and New Caledonia about 23 million years ago. New Zealand seems to have dealt well with its status as ‘just the tip of Zealandia’ and it may want to share how it copes with Iceland. Why? An international team of geologists has proposed that Iceland is just the exposed tip of Icelandia – a sunken continent stretching from Greenland to Europe which may be evidence that Pangaea, the giant supercontinent Gondwanaland was once part of, never fully broke apart. If this is true, it changes not only the geological history of Iceland, but of the entire North Atlantic region. Take that, Zealandia!
The accepted progression of the breakup of Pangaea (public domain)
“It may comprise blocks of full-thickness continental lithosphere or extended, magma-inflated continental layers that form hybrid continental-oceanic lithosphere. It underlies the Greenland-Iceland-Faroe Ridge and the Jan Mayen microplate complex, covering an area of ~600,000 km2. It is contiguous with the Faroe Plateau and known parts of the submarine continental rifted margin offshore Britain. If these are included in a “Greater Icelandia,” the entire area is ~1,000,000 km2 in size.”
The Geological Society of America recently published a chapter of a new book, “In the Footsteps of Warren B. Hamilton: New Ideas in Earth Science,” in which Dr. Gillian Foulger, Emeritus Professor of Geophysics in the Department of Earth Sciences at Durham University (UK), Dr. Laurent Gernigon of the Geological Survey of Norway and Professor Laurent Geoffroy of the Ocean Geosciences Laboratory, University of Brest (France), lay out their arguments in support of the existence of Icelandia – their name for the one million square kilometer area (400,000 square miles) that is big enough to be called Greater Icelandia and is actually bigger than Australia. Why hasn’t anyone proposed this before?
“Until now Iceland has puzzled geologists as existing theories that it is built of, and surrounded by, oceanic crust are not supported by multiple geological data. For example, the crust under Iceland is over 40 km thick – seven times thicker than normal oceanic crust. This simply could not be explained.”
In a press release, Dr. Foulger explains that many geologists have suspected a sunken continent because the oceanic crust around Iceland is far thicker than those in other areas. Lacking any other explanation, she and her team plugged ‘continental crust’ into their models and the starfish suddenly lined up and spelled out ‘submerged continent’. However, this then scrambled the accepted history of Pangaea, which was supposed to have broken up around 50 million years ago. While this is important to geologists looking at the history of the planet, it creates a big problem for lawyers. Lawyers?
“Countries around the world are spending enormous resources conducting subsea geologic research in order to identify their continental shelves and claim exclusive mineral rights there. Research like Professor Foulger’s, which forces us to rethink the relationship between seabed and continental geology can have far-reaching impact for countries trying to determine what area of the seabed are their exclusive preserve and what areas are to be governed by the International Seabed Authority as the ‘common heritage of humankind’.”
Who owns what’s under the ocean around Iceland?
It’s nice to know that someone is concerned about the ‘common heritage of humankind’, but Professor Philip Steinberg from Durham University’s Centre for Borders Research warns that this could be a big fight for mineral rights — perhaps even bigger than the one currently going on around the North Pole as the Arctic Ocean loses its ice and becomes navigable year-round by the oil-drilling nations that border it. Professor Foulger and her co-authors are more concerned about what steps are next to prove the existence of Greater Icelandia — magnetotelluric surveying in Iceland; ultralong, full-crust-penetrating reflection profiling along the length of the Greenland-Iceland-Faroe Ridge; dating zircons collected in Iceland; deep drilling; and reappraisal of the geology of Iceland.
If there indeed is a Greater Icelandia, it’s a bigger deal than Zealandia. Let’s hope the ‘common heritage of humankind’ can survive.
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