A dashed “drawn” at the bottom of the ocean, in the Azores, is making the rounds on social media. The US Oceans and Atmosphere Administration (NOAA) shared on Twitter photographs that were captured during the “Voyage to the Ridge 2022” expedition – trip to the mountain range, in Portuguese – and opened doors to the imagination of internet users.
“On the dive of the ‘Okeanos [Explorer]’ Saturday, we saw several sublinear sets of holes in the sea floor. The origin of the holes has left scientists baffled. The holes look man-made, but the small piles of sediment around them suggest they were dug by… something. What is your hypothesis?”, can be read in the publication of the 25th of July.
These marks, identified more than 2,500 meters underground, are known as “Lebensspuren” – a German term meaning “traces of life”. “These are structures that we find in the sediments, usually at a depth of more than a thousand meters”, explains Telmo Morato, a researcher at the Research Institute in Marine Sciences of the University of the Azores – Okeanos, to SIC Notícias. “They are relatively common in abyssal plains and in areas with a sedimentary bottom (sand or mud)”, he continues.
There are several theories about the origin and functionality of these holes, but so far, there are no certainties. According to one theory, these holes are created by fossils of living beings, eggs or marine animal waste. There is another one where it is said that these holes are sources of oxygen.
“They are thought to be made by marine organisms, but still no one in the international scientific community has managed to understand who makes these structures in the middle of the sea and why this exists”, adds the researcher.
Once explained, the mystery of the holes can become less interesting than the investigation of the ocean floor, which is taking place in the archipelago and which has the participation of Portuguese researchers.
A mission with Portuguese researchers
The shared photos were captured during the second part of the “Voyage to the Ridge”, which takes place off the Azores archipelago. The US ship “Okeanos Explorer” is docked in Faial and is preparing to return to sea this Saturday with a Portuguese specialist on board: Joana Xavier, a researcher at the Interdisciplinary Center for Marine and Environmental Research at the University of Porto.
However, since it began to be planned, the mission has had the participation of a group from the Okeanos research institute. In the buildings of the University of Aveiro, in Faial, an expedition control center was developed from which the mission planning of the ship “Okeanos Explorer” and all dives carried out by the remotely operated vehicle (ROV) is carried out. ) that are performed.
“Okeanos from the University of the Azores has several roles in this mission of the [navio] ‘Okeanos Explorer’: one of the objectives of our research line is to map the biological communities, the species, the natural capital of the Azores region with an emphasis on the Mid-Atlantic Ridge [a cordilheira que existe no fundo do oceano Atlântico e que atravessa o arquipélago]. As there are no large research vessels in the Azores, we do not have ROVs and the Portuguese ROV is rarely available to come to the Azores, it is difficult to put this line of investigation into practice. The partnership with NOAA and ‘Okeanos Explorer’ is not only good for the global scientific community, but also fits into our line of research”, explains Telmo Morato.
The project began to be thought in 2017, but only this year came to fruition. The researchers “sent several notes of interest to ‘Okeanos Explorer’ and NOAA for a campaign dedicated to the Mid-Atlantic Ridge” and the mission received a positive opinion from the North American institution, having been scheduled for 2019. shutdown to the US budget, during the Trump Administration, and the covid-19 pandemic delayed the project several years.
The mission, which is made up of three parts, started in March 2022 and runs until September. The objective is to study the deep ocean, in particular the Mid-Atlantic Ridge, its ridges and seamounts and the existing biodiversity in this region of the Atlantic Ocean.
Other missions at the same time to discover the ocean floor
In addition to the partnership with NOAA and the mission on the ship “Okeanos Explorer”, the researchers from the University of the Azores also have other exploration missions underway in the Mid-Atlantic Ridge.
One of these missions resulted from a partnership with the European Alliance of Infrastructures for Marine Research – Eurofleets, through which the Dutch ship “Pelagia” was assigned to a team led by researchers from Okeanos – University of the Azores. The two missions are taking place simultaneously and complement each other: “We were in permanent contact with “Okeanos Explorer” to coordinate the sites where we were going to work in “Pelagia” so that there would be no overlap, but to complement each other and have more visited sites”, says the researcher.
Also with the vessel “Arquipelago”, equipped with a camera system developed by the Institute for Research in Marine Sciences – Okeanos, expeditions are being carried out, at lower depths, to create “an idea of what exists in the deep sea of the Azores and of the distribution of the different species” by the region.
“We ended up dividing the work into visiting different places and depths”, explains Telmo Morato, adding that this mapping of the deep ocean and biodiversity will also contribute to increasing the network of marine protected areas in the Azores. The initiative is from the regional government and the information is being transferred to the Executive “almost in real time to inform the decision of which areas to choose these decisions”.