New insights into earthquakes off the Irish coast, the potential for enhanced tsunami warning systems, and the migration patterns of North Atlantic whales are among the topics on which key information will be obtained in the coming weeks, thanks to data collected by one of the boldest deep-ocean research projects ever undertaken in Europe.

The SEA-SEIS project, led by scientists from the Dublin Institute for Advanced Studies (DIAS), deployed a network of state-of-the-art ocean bottom seismometers across the entire Irish offshore area in 2018. An expedition to retrieve the seismometers will depart from Galway Port this evening (25.04.20).

The expedition is proceeding during the current Covid-19 crisis because of its time-sensitive nature and the high value of the equipment and data involved.

Commenting today, Professor Chris Bean, Head of Geophysics at DIAS, said: “As the expedition gets ready to set sail, we are conscious that people in Ireland and around the world find themselves in isolation, confined to their houses. The SEA-SEIS scientists, having already been in home isolation, will join the confines of the ship with a skeleton crew in an effort to recover this sophisticated equipment that is currently on the sea floor, and the valuable scientific data that has been recorded.

“When the seismometers were deployed in 2018, they were programmed to run until this time period. Unfortunately, that means this expedition is now time-critical: if we don’t retrieve the equipment in the coming weeks, we risk losing the valuable seismometers – and the even more valuable data they have collected.”

The expedition will be comprised of six researchers and a small crew, who will spend the next three weeks on board the RV Celtic Explorer.

Commenting in advance of their departure, Dr. Sergei Lebedev, a seismologist at DIAS and the leader of the SEA-SEIS project, said: “Eighteen seismometers were deployed in 2018, across an area spanning over 1,500 kilometres from North to South and over 1,000 kilometres from East to West, with some sensors placed in the UK and Iceland’s waters, as well as in Ireland’s offshore territory. 

“Our mission with this current expedition is to retrieve these hugely valuable seismometers and the unique data they have recorded. Our plan is to go south from Galway to the southernmost station first, which is about 400 kilometres off the southern Irish coast. We will then make our way back up along the western coast, retrieving the seismometers as we go, heading towards Iceland and circling back around with the aim of returning to Galway in about three weeks’ time.”

Recordings of earthquakes and the songs of the great whales

Dr. Lebedev said the data captured by the seismometers over the past 18 months will shed light on the nature, occurrence and frequency of earthquakes off our coast, and be fundamental to further work on this topic.

“The current nature and history of the ocean floor along Ireland’s coast is key to our understanding of how the Atlantic evolved and is evolving, and this is important for better understanding both the natural hazards and natural resources offshore,” he said. “For example, slope failures triggered by earthquakes can generate tsunamis in the Irish offshore territory – the data will give us new insights into this hazard.

“From the seismometers, we will be able to obtain recordings of earthquakes off the coast of Ireland. To date, these have been poorly understood, but we know they are generally larger than the ones Ireland has onshore. The new data will give us much greater insights into earthquake mechanisms and, also, into the structure of the Earth’s interior.

“The capturing of information on the life and movements of the great baleen whales of the North Atlantic is also important in terms of understanding the lives of these creatures and the dangers they face. The instruments have made continuous, 18-month-long recordings of the songs of the great baleen whales, including the Blue, Fin, Humpback and North Atlantic Right whales. These unique recordings will build our understanding of the migration patterns of the Earth’s largest animals and their acoustic environment, known to be crucially important for them.”

Vast offshore territory

Professor Chris Bean said: “Many people do not realise how vast Ireland’s offshore territory is. In fact, 90 per cent of Ireland’s territory is offshore, most of it to the west of the country.

“Far beneath the ocean waves, there are spectacular mountains and deep valleys, with steep slopes and elevation drops of up to four kilometres. There are also many extinct volcanoes, similar to those that formed the Giant’s Causeway.

“The SEA-SEIS project aims to uncover new insights about this territory. It is the first project ever to deploy a network of seismometers across such a large area of the North Atlantic. The results of the expedition setting out today will play a crucial role in furthering our understanding of the structure, evolution and seismicity of Ireland’s offshore territory.”

Engagement with schools

The ocean bottom seismometers being collected over the coming weeks will be familiar to many secondary-school students throughout Ireland. Before the seismometers were deployed in 2018, DIAS ran a competition inviting students to name each one. As a result, the seismometers placed across the North Atlantic seabed bear names ranging from ‘The Dude’ to ‘Gráinne’, ‘Luigi’ and ‘The Loch Ness Mometer’.

“When we deployed the seismometers back in 2018, we provided video links from the ship, so school students could watch as the seismometers they named entered into the depths of the Atlantic Ocean,” said Dr. Sergei Lebedev.

“For this year’s expedition, students and anyone with an interest in the SEA-SEIS project can follow our progress from the time we set sail this evening. Through social media and blogs from the research team on board, people at home can track the journey of the RV Celtic Explorer and the retrieval of the seismometers over the next three weeks.”

A video preview of the expedition is available at: https://dias.ie/SEA_SEIS_Expedition_2020 

FAQs – SEA-SEIS Expedition 2020