29 March 2019
The MD19-3581 core – 69.73 m long – sets the world record for core length on board the Marion Dufresne, a ship of the French Oceanographic Fleet operated by Ifremer. This result obtained with the giant corer Calypso is the result of a collaboration between Ifremer, CNRS and the French Polar Institute.
On Tuesday, March 5, 2019, north of the Crozet Archipelago, in rather bad weather, the Calypso corer was deployed at a depth of more than 2,300 metres, with a 70.2 metre long tube. After 9 hours of operation, it came back perfectly straight and completely filled, with a recovery rate of 99.3%. The last record for core length was a 64-metre core in a 65-metre tube in the Gulf of California, a record also held by Marion Dufresne since 2002, when it was operated by the French Polar Institute for its oceanographic activity.
Sediments dating back a million years
The core was obtained during the Crotale* campaign, coordinated by the CNRS, on the circum-antarctic current, its evolution on a geological scale, and its role in atmospheric CO2 variations. Preliminary measurements on board suggest that the core covers the last million years. It would therefore allow studies on the latest climate cycles at very high resolution.
This performance is the result of a series of technical improvements to the core drilling system, carried out by Ifremer, CNRS and the French Polar Institute. The ship’s renovation carried out by the Polar Institute in 2015, and initiated thanks to EquipEx CLIMCOR, has also made it possible to promote this type of coring, with in particular a better equipped gantry crane and a clearer corridor space.
Details on the French Oceanographic Fleet website.
The Marion Dufresne is now part of the French Oceanographic Fleet, a very large research infrastructure that was unified in 2018 and operated by Ifremer on behalf of the entire French scientific community.
It is a multi-purpose vessel that performs two main functions, oceanographic research, on all non-ice oceans, under the responsibility of Ifremer, and logistics of the French sub-Antarctic islands: the Crozet and Kerguelen archipelagos, and the Amsterdam and Saint-Paul islands, under the responsibility of the French Southern and Antarctic Lands (TAAF).
It is one of the largest oceanographic vessels in the world fleet (120 m long) and covers almost all areas of oceanography. Its giant Calypso corer has enabled it to reach records for core length since the late 1990s. For more than 20 years, scientific teams from the major countries of the major industrialized countries (United States, Germany, United Kingdom, China and Japan in particular) have benefited from Marion Dufresne’s performance during international cooperation campaigns in all the seas of the world.