Volcanic Activity and the Irish Landscape

Volcanic activity has had various effects on the Irish landscape. Extrusive landforms like the Antrim-Derry plateau and intrusive landforms like the Leinster Batholith have been formed.

Antrim-Derry plateau

This is an extrusive landform that occurs when tectonic plates separate due to convection currents. Magma is released onto the surface. It spreads across the plateau and the lava cools quickly due to the cold air. This is called a fissure eruption, which forms a lava plateau.

The quick cooling forms extrusive igneous rock like basalt. This rock has no crystals as it cools quickly and has a black texture.

The Antrim-Derry Plateau is a lava plateau in Ireland. It includes the Giant's causeway, which has 60,000 hexagonal basalt columns.

Leinster Batholith

This is an example of a pluton. This type of landform is intrusive and forms under the Earth's surface.

Magma seeps into the bedding planes of rock. It cools slowly as it is kept warm by the surrounding rock.

Plutons consist of intrusive igneous rock like granite, with many crystals and a grainy texture.

Plutons are designated by their shape and size. The largest is the batholith (see diagram).

The Leinster Batholith in Wicklow is an example of a pluton. It can be seen from the surface due to weathering.

Plutons:

[Image showing different types of plutons]

[Second image showing pluton formations]