DALLAS (April 09, 2020) – After making the first manned dive to the deepest point in the Red Sea, investor and explorer Victor Vescovo’s Caladan Oceanic team conducted the first-ever mapping of the Amirante Trench near Seychelles. The Amirante Trench is approximately 610 km long and 30 km wide. The oceanography of the trench has been highly debated among geologists and geophysicists since the late 1970s. While early theories suggested the trench formed through traditional subduction methods, more modern assessments argue that the evolution of the Amirante Trench is more complicated and tied to the separation of India and the Seychelles.
“Over 90% of the seafloor remains unexplored, and with our unique sonar and submersible assets, we are trying to help map the deepest areas that remain a mystery,” Vescovo commented. “We are doing all of this mapping pro bono for the greater scientific good, and we will be donating this and other data to the GEBCO 2030 mapping initiative.”
The Amirante Trench was mapped over three days from March 26 to March 29, 2020. Two passes about five kilometers apart were collected along the full shape of the trench to produce a full-coverage map. These data sets, along with 14,830 square kilometers of transit data (to and from the trench), were collected within the Seychelles EEZ in collaboration with the Government of Seychelles, represented by the Ministry of Environment, Energy and Climate Change. Except for a large – and previously undocumented – seamount on the southern end, the trench is wide and featureless with a very small, gentle slope (less than one degree) running north to south.
“These data have shown the previously unknown topography of the Amirante Trench in surprising detail,” said marine geologist Heather Stewart. “A previously unknown seamount was discovered in the southernmost part of the trench. [It’s] unbelievable that this underwater mountain was previously undiscovered, considering it is over 1000 meters high. The newly discovered ‘Amirante Seamount’ adds to this global database of knowledge, and further study will reveal the geodiversity and biodiversity it hosts.”
“The Amirante Trench is a really interesting deep-sea topographic depression. It has all the hallmarks of a deep subduction trench, but is not,” said lead scientist Dr. Alan Jamieson. “As the deep Indian Ocean is often lacking in very high-resolution mapping, work like what has just been done on the Pressure Drop is incredibly important in understanding what the seafloor looks like now, how it got to be like that, and the geological processes that are underpinning it. Any new maps of the deep Indian Ocean are great and long overdue. Compared to the satellite-derived maps, our new echosounder’s 3D digital renderings are like Caravaggio going back to redraw a Monet.”
For the next – and last – phase of the 2020 expeditions, Caladan Oceanic will travel to Guam for multiple dives around the western edge of the famed “Ring of Fire” in the Pacific Ocean. The Caladan crew plans to revisit the bottom of Challenger Deep up to six times for scientific mapping purposes, as well as dive in never-before-visited deep areas in the northern part of the Mariana Trench. In July, they hope to explore the seafloor off Samar Island, Philippines, and execute what could become the deepest wreck dive in history.