The operation began on October 21, when the company in charge of the installation of the water supply system requested, through the General Water Directorate of the Ministry for the Ecological Transition and the Demographic Challenge (MITERD), the urgent intervention of the Institute. Oceanography Spanish to locate the anchor and connection of the submarine pipeline of the tanker.
Thanks to the ROV Liropus underwater vehicle, the area where the anchor was lost was visually inspected, according to the information provided by the company, in addition to the slope, up to a depth of 240 meters. After six hours of tracking, it was concluded that the anchorage could destabilize and fall through a small underwater canyon and reach another area. For this reason, the IEO marine geology team aboard Ángeles Alvariño chose to carry out a bathymetry Very high resolution with which to try to locate the anchor or at least limit the possible search areas.
Search and location of the anchorage under the sea
Once the data were processed, three possible points where the anchor could be found were defined based on the mapped morphologies, the acoustic impedance and the possible trajectories that the structure would have followed according to the slope.
In the first of the sampled points, the structure was located and its recovery was carried out, a complex operation to tie the anchor, located more than 130 meters deep, with the underwater vehicle and thanks to the work on the deck of the crew by Ángeles Alvariño.
After two days of operation, the scientific team resumed their work in front of the lava delta for the physical-chemical and biological characterization of the water column and the daily mapping of the advance of the lava in depth carried out by the Spanish Institute of Oceanography within the framework of the Vulcana (Canary Submarine Volcanology) project.
The IEO-CSIC ship Ángeles Alvariño arrived in La Palma on October 17 to continue the work carried out in a previous campaign by the ‘Ramón Margalef’ in the framework of the volcanic eruption. A team of oceanographers, geologists and microbiologists is studying how the marine ecosystem can be affected by the arrival of lava into the ocean, both in the benthic habitat (the one linked to the bottom), and in the pelagic (linked to the water column).
To do this, they perform new cartographies of the advance of the lava delta in the ocean; and they take water samples at different depths -both outside the exclusion perimeter, and a few meters from the wash thanks to the drones of the Seadrons team of the Andalusian Institute of Marine Sciences (ICMAN-CSIC). The ROV Liropus 2000 underwater vehicle allows them to take rock, gas, fauna and water samples and high definition images with which to characterize not only the advance of lava in the sea, but its impact on benthic habitats.