According to new theories by geophysicists, Iceland could be the last remaining remnant of Icelandia, a continent of almost Texas size that submerged beneath the North Atlantic Ocean around 10 million years ago.Although the theory is contrary to long-held ideas about Iceland's formation and the North Atlantic, the researchers claim it explains the ocean floor's geological features and why the Earth's crust below Iceland is thicker than necessary. Live Science was told by outside experts that they doubt Icelandia is possible based on the evidence so far.However, even if geological research supports the theory, this radical new idea of an unexplored continent could have implications regarding the ownership of fuels beneath the seafloor. These fuels, according to international law, belong to any country that can prove that their continental crust extends beyond the seafloor.Gillian Foulger, the lead author of " Icelandia," said that the region with continental material beneath it stretched from Greenland and Scandinavia to describe the new theory. This chapter is part of the book "In The Footsteps of Warren B. Hamilton : New Ideas in Earth Science" (Geological Society of America 2021). It is still higher than it should, although some of it has sunk below water's surface in the east and west. Foulger, an emeritus professor in geophysics at Durham University, said that if the sea level fell 600m [2,000 feet], then there would be a lot more land on the ocean's surface." Live Science was informed by Foulger."Icelandia" was a continent that existed between Greenland, Scandinavia and Ireland up to 10 million years ago. A submerged area west of Britain and Ireland made up "Greater Icelandia." (Image credit: Gillian Foulger/Google Maps)Lost continentFoulger stated that the North Atlantic region was once completely dry and made up the supercontinent Pangaea between 335 million and 175 million years ago. Geologists have known for a long time that the North Atlantic Ocean basin formed when Pangaea broke apart 200 million years ago. They also believe that Iceland was formed 60 million years ago, above a volcanic plume at the center.Related: Photo timeline: How Earth was formedFoulger and her coauthors propose a different theory. They believe that the oceans formed roughly south and north, but not west or east of Iceland when Pangaea collapsed. The geologists stated that the regions to the east and west were still connected to Greenland and Scandinavia.Foulger stated that people have a very simplistic view of tectonic plates. They think they are like a dinner plate. It splits in half and then moves apart. It's more like a pie, or piece of art made from different materials, such as fabric and ceramic, so different parts have different strengths.Foulger stated that Pangaea did not split up cleanly and that the island of Icelandia, which was about 200 miles (300 km) in width, remained intact above the waves until approximately 10 million years ago. She said that Iceland was the only remaining island after the western and eastern ends of Icelandia fell.According to geologists, this theory would explain why Iceland's crustal rocks are only about 25 miles (40km) thick rather than about 5 miles (8km) thick if Iceland was formed over a volcanic plume.Foulger stated in a statement that "when we considered the possibility of this thick crust being continental, all our data suddenly made sense." "This made us realize that the continent was larger than Iceland and that there is an underground continent."Continental shelfFoulger and her coworkers estimated that Icelandia once covered more than 230,000 sq mi (600,000 km) of land between Greenland & Scandinavia. This area is slightly smaller than Texas. Iceland today measures approximately 40,000 square miles (103,000 km).Similar: Photos: The strangest geological formations in the worldThey also suggested that there was another similar-sized region to the west of Britain and Ireland, which they called "Greater Icelandia". They said that the same region has also fallen under the waves.Fossil evidence has shown that certain plants that spread by dropping seed are identical in Greenland as well as Scandinavia. The authors stated that this finding supports the theory that the two regions were once connected by a large strip of dry land. The geologists don't know of any fossil evidence that animals once lived on this continent.Director of Durham University's Centre for Borders Research Philip Steinberg said that the new theory of Icelandia could impact the ownership of fossil fuels below the seafloor. According to international law, countries are allowed to claim fossil fuels if evidence shows that the resources lie beneath their continental shelf, which is a relatively shallow area of the seafloor that can stretch hundreds of miles beyond the coast.Related: Canada claims the North PoleSteinberg, who wasn't involved in the Icelandia research noted that many countries spend large sums of money on geoological research that could enable them to claim exclusive mineral rights below their continental shelves.Steinberg stated in the statement that "research like Professor Foulger's can force us to rethink how seabed and continental geoology relate"The idea of Icelandia is contrary to the prevailing theories about the formation of North Atlantic regions. This is why prominent geophysicists and geologists are against it.Ian Dalziel, a geologist from the University of Texas of Austin who won the Penrose Medal last month for his work on past supercontinents and ancient geography, stated that he couldn't see any reason to support the proposal.Dalziel explained to Live Science via email that Icelandia was not formed from continental crust material, unlike the sunken continent of Zealandia which, according to geologists, was made of continental crust that had separated from Antarctica.Live Science was informed by Alexander Minakov of University of Oslo and Carmen Gaina, Director of Centre for Earth Evolution and Dynamics, that the proposal was "bold" and had many problems. They also said that Icelandia is unlikely.They said that magnetic surveys of the North Atlantic seafloor show "stripes", which indicate when successive layers molten crust were laid on the North Atlantic seafloor. This is a clear indication of oceanic crust, also found in large oceanic plateaus of the Pacific Ocean.However, "their conceptual perspective is a good point for discussions and, more importantly for more and more relevant data collection," Gaina and Minakov stated. They also suggested further geological drilling of the seafloor and seismic surveys to measure the crust based on its seismic echoes from calibrated explosions conducted by research ships.Original publication on Live Science