ABYSSA's magic trick for detecting Seafloor Massive Sulphide

The So Magical fleet is specifically designed for detecting Seafloor Massive Sulphide deposits at the sea floor.

Comprising several autonomous underwater vehicles able to cover vast tracts of the ocean floor, the So Magical fleet will be able to detect this rare and valuable mineral more efficiently and more rapidly than any other detection technique currently available.

So-Magical : Seafloor-Ore MAgnetic and Geosciences Investigation with Communication by Acoustic Link !

Seafloor Massive Sulphide deposits

Seafloor Massive Sulphide deposits are small geological bodies (usually around 10 to 500 m across) found at depths of around 2500 m, and formed as a result of deep-sea hydrothermal activity. These sulphide deposits are rich in metals, making them a much sought-after mineral resource. The problem is that these geological deposits are not easy to find – it really is like looking for a needle in a haystack!

It is also a challenge to find inactive geological sites where the biodiversity is not so rich and the environment is not so sensitive. In addition, they are not associated with thermal or chemical anomalies, making them hard to detect using conventional methods that look for such anomalies in the water column.

© Ifremer/CNRS, MOMARSAT, 2020 – https://doi.org/10.18142/130

How, then, can we possibly detect active and inactive Seafloor Massive Sulphide deposits in the immense expanses of the oceans?

This is the question that we started to address in our R&D work back in 2014-2015, leading to the concept of the So Magical fleet.
Our So Magical fleet will deploy two types of AUVs: a ‘leader’ AUV and a group of ‘follower’ AUVs guided by the information transmitted by the leader AUV over an acoustic link.

The Leader AUV

The leader AUV is a tried-and-tested deep-sea AUV equipped with multiple sensors and a dual acoustic communications system: the first is a long-range link designed to communicate with the surface vessel, while the second is a short-range link used to communicate with the squad of follower vehicles.

The follower AUV

The follower AUVs innovate with a simplified system of navigation and positioning sensors as well as onboard scientific sensors. This simplified sensor platform makes the vehicles much lighter, significantly reducing unit costs per AUV. To detect Seafloor Massive Sulphide deposits, we use the specific magnetic signature of sulphide bodies, an efficient technique for identifying active and inactive sites. All our So Magical AUVs will therefore be equipped with 3-component magnetometers.

The fleet is designed for the deployment of up to seven AUVs working as a coordinated pack to map a target area at depths of as much as 3000 m below the surface. Our fleet will thus provide an extremely efficient and effective approach for systematically surveying the deep ocean floor and detecting Seafloor Massive Sulphide deposits.

Our key partners

RTSys for the development of the follower AUVs and their short-range acoustic link platform
IPGP for the use of deep-sea magnetic data to detect mining sites