tectonic activity in Ireland

Laurentia and Avalonia

850 Million Years ago, Ireland existed on two continents called Laurentia and Avalonia.

These continents were separated by an ocean called Lapetus

Northern Part of Ireland and southern part of the islan

The northern part of Ireland was located on Laurentia - would go on to form large parts of today’s North American plate.

southern part of the island was located on Avalonia.

470 MYA

the lapetus ocean began getting smaller and evenutally disappeared.

This happened because the Laurentia and Avalonia plates were colliding.

Effects of the Colliding

The effects of the colliding of Laurentia and Avalonia can still be seen today.

Running down the middle of the country from Clogerhead in Louth, to the Shannon Estuary in the west is the Lapetus Suture.

Lapetus Suture is..

a scar on the landscape that shows the line where the plates crashed and the lapetus ocean disappeared.

Some marine sedimentary rocks formed on the lapetus ocean can now be found on Howth Head, Bray head and the Sugarloaf mountains".

Irelands mountain and rocks - Tectonic activity

most of Ireland’s rocks are formed as a result of tectonic activity.

After the Lapetus ocean closed, various plates continued to collide, resulting in the Caledonian Orogeny (490-390 MYA)

This tectonic movement resulted in the Bluestack and Wicklow fold mountains occurring in Ireland.

400 MYA - continental drift

400 MYA continental drift continued to move Ireland closer to the equator.

During this Carboniferous period Ireland sank beneath tropical sea → formation of majority of the sedimentary rocks

e.g sandstone and limestone that now covers Ireland.

Example of this is The Burren in Co. Clare

250 MYA

about 250 MYA, the Eurasian and African plates collided. This armorican Orogeny resulted in the mountains and valleys of Munster.