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  The wreck of the Titanic lies in two parts at the bottom of the North Atlantic Ocean, slowly decaying nearly 4,000 meters (13,000 feet) below the surface, but it is not alone.  A sonar detection some 26 years ago has now revealed that there is much more to this underwater area than previously thought.   

  PH Nargeolet, a veteran Nautile submarine pilot and Titanic diver, originally picked up the echo equipment in 1996, but its provenance remained unknown.   

  On an expedition to the wreck of the Titanic earlier this year, Nargeolet and four other researchers went to the previously recorded location of the blip to search for the mysterious object it represented.  Because of its size, Nargeolet thought he was looking for another wreck — instead he found a rocky reef, made up of various volcanic formations and thriving with lobsters, deep-sea fish, sponges and many types of coral that may be thousands of years old.   

  “It’s biologically fascinating.  The animals that live there are very different from the animals that live in the deep ocean,” said Murray Roberts, a professor of applied marine biology and ecology at the University of Edinburgh in Scotland and one of the researchers on the expedition.  “(Nargeolet) did a really important scientific work.  He thought it was a wreck and it turned out, in my mind, even more amazing than a wreck.”   

  The abyssal plain is a term used to describe the ocean floor at a water depth of 3,000 to 4,000 meters (about 12,000 feet), which makes up 60 percent of the Earth’s surface, according to Roberts.  It is thought to be a featureless, muddy bottom with no particular structure.  On a few occasions, divers have observed rock formations on the plain.  Since the recent discovery near the Titanic, Roberts now believes that such features may be more common than previously thought.   

  Rocky areas may also explain the distances sponges and corals travel on the ocean floor, which has always been a mystery to scientists.  Within the muddy environment where they are usually found, there are few hard surfaces that these species can attach to in order to grow and reproduce.   

  “Sometimes they show up in places where we think, ‘Well, how did they get there?’  They don’t live long enough to get there,” Roberts said.  “But if there are more of these rocky places, these stepping stones, than we ever thought, I think it could help us understand the distribution of these species throughout the ocean.”   

  The researchers are currently working on analyzing images and videos taken from the reef during their dive and plan to share their findings to improve the scientific community’s collective knowledge of life in the deep sea.  Roberts also hopes to link this discovery to a wider Atlantic Ocean ecosystem project he is leading, called iAtlantic, which will enable further study and protection of the fragile ecosystem within the reef.   

  There is another sonar blip near the Titanic that Nargeolet hopes to detect on a future mission.  It was recorded in the same survey he carried out years ago, between the Titanic wreck and the newly discovered reef – now named the Nargeolet-Fanning Ridge in honor of him and 2022 mission specialist Oisín Fanning.  Nargeolet expects whatever it is to be bigger than this reef.   

  OceanGate Expeditions and their foundation – which, along with Fanning, provided the financial support for Nargeolet’s dive this year – will continue their long-standing research project of the Titanic and its surroundings in 2023.   

  “The marine life… was so beautiful.  It was really incredible, because I never expected to see this in my life,” said Nargeolet.  “I’ll be more than happy to keep looking at Titanic.”