As legend and Gaelic mythology has it, Giant’s Causeway in Ireland was created by the Irish giant Fionn MacCumhaill after accepting a challenge to fight his Scottish rival, Benandonner, but scientists had a different theory in mind and have now conclusively determined how the mysterious structure was actually formed.
With no danger from giants, scientists chose the lab as their working place so they could perfectly recreate the scientific process behind the creation of the Giant’s Causeway and its 40,000 geometric columns. While columns of volcanic rocks such as these are not at all unusual, scientists were not completely clear on the exact temperature needed for cooling magma to create a structure like this, as The Guardian report.
The University of Liverpool’s Yan Lavallée explained that geologists have long wondered what kind of temperatures were needed to create fractures such as those found on Giant’s Causeway, whether hot or cold.
“This is a question that has fascinated the world of geology for a very long time. We have been wanting to know whether the temperature of the lava that causes the fractures was hot, warm or cold.”
The University of Liverpool finally came up with the answer to this question, and found that in order to create fractures of this kind, temperatures of 1,544 to 1,634 degrees Fahrenheit are needed, according to ScienceAlert.
— Belfast Telegraph (@BelTel) April 14, 2018
To fully test how a structure like Giant’s Causeway was formed, scientists were able to take basaltic columns from Iceland’s Eyjafjallajökull volcano, which they heated until the temperature of the column samples finally reached a whopping 1,832 degrees Fahrenheit. Afterwards, scientists then cooled the columns into lava.
By this process, scientists were able to take a closer look to determine at just what point the rock began to fracture. As Anthony Lamur explained, while this experiment may have taken a lot of difficult work, scientists were finally able to learn how these kinds of sites are created.
“These experiments were technically very challenging, but they clearly demonstrate the power and significance of thermal contraction on the evolution of cooling rocks and the development of fractures.”
Along with the 50- to 60-million-year-old Giant’s Causeway, there are other structures of this kind that can be found in both Iceland as well as the United States, and scientists have even noticed geometric columns on Mars.
When it comes to practical use, scientist Jackie Kendrick noted that the recent study could help greatly when it comes to future research on geothermal and volcanic studies.
“Fluid flow controls heat transfer in volcanic systems, which can be harnessed for geothermal energy production. So the findings have tremendous applications for both volcanology and geothermal research.”
The new research conducted on the formation of Giant’s Causeway in Ireland can be read in Nature Communications.