The Giant’s Causeway, located in Country Antrim, Northern Ireland, is one of the UK’s most instantly recognisable natural landmarks. The distinctive columnar landscape was formed during intense volcanic activity which forced molten rock up through cracks in the earth. Thick lava flows then cooled, contracted and cracked, creating around 40 000 basalt columns that are renowned for across the world.

Research by the Geological Survey of Northern Ireland (GSNI) and the British Geological Survey (BGS), has changed our scientific understanding of Northern Ireland’s volcanic past including the Giant’s Causeway, revealing that that volcanic rocks of the region formed in just 5.5 million years – this is 8 million years less than previous estimates.

Using state of the art techniques, scientists have been able to reconstruct a new timeline for volcanic activity across Northern Ireland. It now firmly connects the Earth processes that caused the development of the Giant’s Causeway and the broader Antrim Plateau area, along with the Mourne Mountains and Slieve Gullion, to a globally significant volcanic event seen in rocks as far away as Greenland and known as the North Atlantic Igneous Province around 60 million years ago.

The Giant’s Causeway is one of the world’s most instantly recognisable landmarks. For decades, it was believed the region’s volcanic activity, responsible for the Giant’s Causeway, stretched over 13.5 million years during a time period we refer to as the Paleogene. Our research shows that this activity was far more concentrated, with geological processes acting much faster than previously thought. These findings have completely changed how we understand the Northern Ireland’s place in the wider North Atlantic volcanic story.

Prof Mark Cooper, GSNI Chief Geologist.

Cutting-edge analysis has allowed us, for the first time, to place the volcanic activity that led to the formation of the Giant’s Causeway within a much more precise global context. It’s a remarkable reminder that the iconic 40 000 basalt columns that we can still see today in Northern Ireland can also help us to understand the globally impacting geological transformations during the Paleogene period.

Dr Simon Tapster, Geochronologist at the British Geological Survey.

This work is part of a wider initiative at the British Geological Survey to improve the understanding of the UK’s geology through better quantifying geological time in the rocks around us.

The research paper, , is now available to read.