World’s Oldest Minerals Discovered in Argentine Patagonia
- Geologists have identified rock formations in northeast Canada that may contain the oldest known materials on Earth, potentially redefining the scientific understanding of the planet's earliest crust.
- The discovery is centered in the Nuvvuagittuq greenstone belt, a coastal outcrop located in Hudson Bay.
- The determination of the rocks' age relied on a specialized technical approach to isotopic dating.
Geologists have identified rock formations in northeast Canada that may contain the oldest known materials on Earth, potentially redefining the scientific understanding of the planet’s earliest crust. An announcement made on July 2, 2025, revealed that these samples date back at least 4.16 billion years, with some estimates suggesting they could be as old as 4.3 billion years.
The discovery is centered in the Nuvvuagittuq greenstone belt, a coastal outcrop located in Hudson Bay. The research team analyzed banded gray lavas and marine chemical rocks to determine the exact moment the ancestral magma cooled and crystallized.
Advanced Isotopic Dating Methods
The determination of the rocks’ age relied on a specialized technical approach to isotopic dating. Rather than using zircon, which is the most common and stable mineral used as a geological clock, the researchers employed two different samarium isotopic clocks that decay into neodymium.
The team specifically tracked the decay of samarium-146 into neodymium-142 and samarium-147 into neodymium-143. Because these two processes have radically different half-lives, comparing them allows geologists to control for biases in age estimation that typically occur in rocks that have undergone metamorphism.
Jonathan O’Neil
Las rocas volcánicas tienen al menos 4,16 mil millones de años; el valor más probable podría llegar a 4,3 mil millones. No hay rocas conocidas más antiguas
Implications for Early Earth History
This finding provides a rare window into the conditions of the Earth during its earliest stages. By analyzing these materials, scientists aim to better understand the origins of the terrestrial crust and the environmental conditions that may have allowed for the emergence of life.
The use of samarium-neodymium dating in the absence of zircon marks a significant technical application in geochronology, allowing for the dating of materials that were previously difficult to analyze with precision due to their metamorphic history.