Mapping the Landscape of the Seabed
Oceans cover 71% of the Earth's surface yet only 5% of the seafloor is mapped. Over 85% of Ireland's designated shelf area has been mapped to date, resulting in one of the largest resources of multi-beam bathymetric data in the world. INFOMAR is considered the best role model for seabed mapping all over the world.
The Atlantic Transect
The first collaborative trans-Atlantic seabed mapping survey happened in 2015 by the Atlantic Ocean Research Alliance on the RV Celtic Explorer. The survey mapped some significant topographic features on the bottom of the North Atlantic seafloor from Newfoundland, Canada to Galway Bay, Ireland. These features include a 3.5 km high underwater mountain (seamount), the Charlie Gibbs Fracture Zone, footprints of icebergs moving across the seabed and an ancient glacial moraine.
The following resources provide a real world case study of plate tectonics, sea-floor spreading and the mid-ocean ridges in action. Teachers could also use the resources to show the effects of glaciation on the North Atlantic sea floor and to examine the human interaction with the sea floor by looking at the laying of the Trans-Atlantic Cable in 1866.
The Seabed around Ireland
Since 1999, the vast seabed off the Irish coast has been mapped using high resolution multi-beam sonar, measuring gravity and magnetic variation, and recovering grab samples for biological, chemical and geological analysis. The resulting, freely available, bathymetric imagery provides the means to view and explore a range of seabed features from sandbanks in the shallower waters to deep-water canyons, seamounts and trenches offshore.
The following resources examine physical geographical features that occur under the seas around the Irish coast. Students can examine the geographical data when studying the plate tectonics, glaciation and rivers of the geography course. Teachers could use the worksheets at the end of the lesson to recap physical features or use the Mahon river quiz to recap the main river terms.
INFOMAR has an interactive online story map to accompany the following worksheets.
The Geology around Ireland
INFOMAR have increased our understanding of the geology of areas of the Irish coastline. The following worksheets are based on the story maps created by INFOMAR. The story maps examine the bedrock and tectonic features such as fault lines beneath the waves of Galway Bay, Kerry, Louth and Meath. The resources would be particularly useful with senior classes to further examine the plate tectonics and rock types section of their Geography course. The accompanying fill in the blank worksheets could be used to revise material covered in classes on plate tectonics and rock types. They are also useful for improving student's literacy and geographical skills of data analysis and computer-generated map interpretation.
Junior Cycle:
Strand 1
Exploring the physical world
1. Describe the formation and global distribution of physical features in the context of tectonic plates and structure of the Earth.
5. Explain how the process of erosion, deposition and transportation shape our fluvial, marine and glacial landscapes.
Leaving Certificate:
Core Unit 1
Patterns and processes in the physical environment
1. The tectonic cycle
2. The rock cycle
Landform development
