A submerged tropical island the size of Iceland has been discovered deep under the water off the coast of Brazil.
A sunken volcanic island, approximately the size of Iceland, thought to have once been covered in lush vegetation, rivers and waterfalls and fringed by beaches and wave-cut platforms, has been discovered off the coast of Brazil, according to new research.
The island sounds like it could once have been a superb scuba diving destination, but unfortunately, we will never know, as it now lies some 600m below the surface of the Atlantic Ocean.
The remarkable discovery of the sunken island was made by a team of British and Brazilian scientists surveying the seafloor around an enormous mid-ocean volcanic plateau called the Rio Grande Rise. As their underwater remotely operated vehicle (ROV) beamed images back to the scientists on a boat, the team spotted some unusual-looking red clay layers.
‘You just don’t find red clay sand on the seabed. The deposits looked like tropical soils’, said Bramley Murton, a marine geologist from the National Oceanographic Centre in Southampton and co-author of the study, which revealed the presence of the island
Using the ROV, the team was able to gather samples of the red clay and bring it to the surface. When the samples were taken back to the laboratory to be assessed, the team discovered their hunch was correct. The unusual make-up of the rock could only have been created in an open-air environment and with exposure to tropical heat and humidity. And, even more intriguingly, the chemical and mineral make-up of the sample was the same as the red earth found in various parts of Brazil.
‘Imagine a lush tropical island slipping beneath the waves and lying frozen in time,’ said Murton, ‘that’s what we’ve uncovered’.
The island’s slide to the bottom of the ocean occurred long ago. The Rio Grande Rise is an 80-million-year-old mantle of volcanic plume born out of the mid-Atlantic Ridge. Over millions of years, it moved slowly westward, closer and closer to Brazil until, around 40 million years ago its western edge gave one final burst of volcanic activity which led to the creation of the island, after which it sunk slowly back under the water again.
However, this sunken island, which lies far out in international waters, is more than just an interesting geological story. The minerals contained within it and the rest of the Rio Grande Rise are potentially valuable and that has governments interested – so much so that the Brazilian government has applied to the UN to have its maritime borders extended out to encompass the Rio Grande Rise.
To do so, the Brazilian authorities must prove that both the Rio Grande Rise and the sunken island have the same geological characteristics as those found in Brazil, and the recent findings help to bolster this claim.
