Due to the movement of the tectonic plates of the Earth, the shell of our planet is constantly recycled, making rocks and minerals from their earliest days incredibly rare. This frustrates geologists, as surface-level Hadean rocks (rocks older than 4.03 billion years) could give a significant understanding of the first geological stages of the 4.5 billion years History.
In a study published today in Early landResearchers from Canada and France suggest that the Nuvvuagittuq Greenstone Belt (NGB) – rock formation in northeastern Canada – could contain Hadean rocks about 4.16 billion years ago. While this date differs from previous controversial investigations identifying NGB rocks as old as 4.3 billion years, it nevertheless increases the wider theory that the rock formation hosts remains of the earliest shell of the Earth. If the new study is shown to be true, it could hold important implications for our understanding of the most ancient history of the planet.
“There are many questions about the earliest crust of the Earth because of the rarity of Hadean (> 4.03 billion) rocks and minerals.
One of the most common ways to date rocks is by radiometric DatingWhich involves measuring the radioactive decay of isotopes – different versions of elements. The claim that some NGB rocks could be up to 4.3 billion years old is controversial, as some researchers maintain that the isotope data on which the estimate is based may actually be the result of “subsequent geological mixed processes” instead Statement.
In the new study, O’Neil and his colleagues explored ancient rocks in the NGB called metagabroic intrusions. Simply mentioned, these metagabre intrusions disrupt older basalt rocks, a feature that the researchers claim, enabled them to combine different isotopian analyzes to reveal lower age for this older material. Specifically, data involving the decay of Samaria isotopes in Neodymia isotopes consistently have shown a minimum age of 4.16 billion years.
It remains to see if the question of the true age of the NGB will ever be solved. The recent study comes by New research on prehistoric traces, also considered controversial for its dating technique. More widely, both articles emphasize the importance of critically evaluating date methods, especially those that could support important historical implications for both humanity and our planet.
