In the past, transatlantic submarine cable systems have often taken a route across the North Atlantic from Europe to Canada, New Jersey, New York and more recently Virginia Beach. The primary focus of the EllaLink system is to offer a new low latency path for those wishing to reach Latin America directly from Europe, and vice versa. The most direct route between Europe and Brazil crosses a particularly challenging area of the seabed, around 1,100 km off the North East coast of Brazil, called the Mid Atlantic Ridge. The Mid Atlantic Ridge is a vast undersea mountain range running down the center of the Atlantic Ocean, from the Arctic in the North to the southern tip of Africa in the South. Due to the movement of the tectonic plates, the ocean floor is slowly spreading apart at a rate of 2 to 5cm a year. The ridge has a deep rift valley along its crest between 1,000m and 3,000m deep, which for perspective, is similar in size to the Grand Canyon.
The Mid Atlantic ridge is roughly equidistant from the continents of Europe, Africa and the Americas. Its peaks range between 2,000m and 4,000m above the ocean floor, it sits in water depths in excess of 5,000m. Some of the peaks of this huge underwater mountain range protrude from the ocean surface to form islands such as the Azores In the North Atlantic and St. Helena in the South Atlantic. With a length of around 18,000 km, hidden under the turbulent waters of the mighty Atlantic oceans, the Mid Atlantic Ridge can be considered to be one of the largest and longest continuous mountain ranges on the planet.
Anyone who has ever been involved with subsea activities such as designing, building and installing submarine cable systems knows that the ocean offers a variety of different challenges, from those we can anticipate, to those we cannot. With challenges such as seismic activity, harsh seabed environments, bad weather, piracy, the subsea industry has seen it all. That is why we rely heavily on the skill, technology and experience of specialist subsea cable manufacturers like ASN, and professional hydrographic survey companies such as Elettra, to assist us by first accurately mapping the ocean floor and then by designing and installing a robust, resilient, and reliable submarine cable system.
Knowing that our system takes a unique path, the EllaLink team, together with ASN and Elettra, have taken great care to design the system by planning a route that will not only enable ease of installation and maintenance but also reduce the risk of external aggression.
The steep seabed slopes and extreme depths coupled with potential seismic activity and an ever-expanding seafloor present a unique set of challenges for marine operations. As part of the route development process our team of marine specialists have assessed the seismic activity over the last 25 years in detail. Interestingly, as part of the pre-survey study analysis has been conducted using the IRIS database [http://ds.iris.edu/ieb/index.html] which demonstrates that the specific route selected for EllaLink to cross the Mid Atlantic Ridge shows less risk of seismic activity than the popular traditional routes across the North Atlantic.
With this data to comfort us, the EllaLink Marine Working Group completed the route design and prepared the survey Route Position List. The hydrographic research vessel, the RV OGS Explora, commenced survey activities for EllaLink at the end of April and by mid-May she had reached the Mid Atlantic Ridge. With the use of a Reson Seabat 7150 Full ocean depth Multibeam Echosounder (MBES), capable of collecting a swath of data up to 10km wide, the survey of this massive underwater geological feature commenced.
The amazing images gathered from this survey footage show us the immense scale and ruggedness of the Mid Atlantic Ridge and gives us an impressive perspective of the engineering challenges that lie ahead. Our unique system design has many great advantages in terms of diversity, latency and security, but the survey has shown us that the EllaLink route is also truly beautiful.