A series of preliminary scientific campaigns carried out from 2011 to 2014: Cap Coral, Coral Corse and MedAtolls, to the north-east of Cap Corse, have revealed new circular formation structures called “coralligenous atolls”, unique bio constructed structures, generally made up of a coralligenous central core and surrounded by a crown of rodholites, blocky formations of organic concretions, mainly calcareous algae. More than a thousand atolls were identified between 110 and 130 m depth during these surveys. These deep coral rings had never been described before and are genuine natural monuments.
In July 2020, during a twenty-eight-minute dive at a depth of 120 metres, Laurent Ballesta observed exceptional biodiversity in these deep atolls, in a remarkable state of conservation.