Maps SEA-SEIS seismic stations, named by students from schools across Ireland. SEA-SEIS seismic stations cover a large area in the North Atlantic. Seismic stations deployed offshore Ireland (red circles) and the ship track of the deployment expedition. Blue square: cruise start, Cobh, near Cork (17 September, 2018). Green square: cruise completion, Galway (4 October, 2018). Ireland’s offshore area is nearly 10 times greater than its onshore territory. Red line: the border offshore. Under the water offshore Ireland, there are spectacular mountains and deep valleys, with steep slopes and elevation drops of 3-4 km. The ocean-bottom seismometer array deployed by the SEA-SEIS Expedition. The ocean-bottom seismometer array deployed by the SEA-SEIS Expedition.