The island of Ireland as we recognise it today is only 10,000 years old and was largely formed by retreating glaciers and falling sea levels, according to an exhibition marking 175 years of the Geological Survey Ireland.
It explains that the ground beneath our feet has rocks that are in some cases 1.7 billion years old, and while Ireland accounts for only a tiny proportion of the Earth’s surface the island has a highly diverse geological make-up.
The exhibition, entitled Down to Earth, will run at Collins Barracks in Dublin for the next 18 months.
It states that some of the rocks that make up Ireland were originally in the Ipathus Ocean, which was located near the South Pole. Volcanos and earthquakes then pushed them northwards to the mid-latitudes.
Ireland is, according to the exhibition, half made up of limestone rock, which developed in the tropics 330 million years ago.
The exhibition includes an artist's impression of an animal which looks like a cross between a crocodile and a salamander, known as a tetrapod. It crawled out of the primordial sea 385 million years ago to become the first animal on Irish ground, with its footprints discovered on rocks in Valentia Island in 1993.
Most of the rocks from the age of the dinosaurs (66 million to 245 million years ago) are located in modern-day Northern Ireland, it says.
Indeed long before the man-made partition there was a natural partition dividing the island diagonally from the Shannon Estuary to Clogherhead, Co Louth.
It was the fault line of two huge primordial continents, meaning the northern half of the island of Ireland belongs geologically to North America and the southern half to Europe.
Ireland settled into the north Atlantic and its youngest rocks are located in the Cooley Peninsula and on the Antrim coast, where the Giants Causeway was formed from basalt 60 million years ago.
Heritage
“This is part of our heritage, but it is not in the curriculum,” said geologist Dr Siobhán Power . “Part of the idea of this is to let people see it. They can run around and look at the beauty of that or they can read all the text and get to grips with it.”
The centrepiece of the exhibition is a huge map of Ireland on the floor detailing the different rock formations in each part of the island.
Minister for the Environment Eamon Ryan, who opened the exhibition, said geology was not ancient history.
“Our understanding of geology in how we manage our land is going to be central to how we manage the climate crisis, restoring biodiversity and protecting out people,” he said.
“That includes ensuring that we don’t have mica or pyrite in our building blocks. That is why this exhibition is important. It is understanding the very ground that we are walking upon.”
