Oldest Rock Discovery on Earth, Its Age is 4.16 Billion Years Old!
Complex Korean , Jakarta - A rock formation on the east coast of Hudson Bay, Canada, is suspected to contain the oldest rocks ever found. bumi In a recent study published in the journal Science on June 26, 2025, researchers referred to the rocks in the Nuvvuagittuq Greenstone Belt (NGB) area as being approximately 4.16 billion years old.
The research team used two methods of radiometric isotope decay dating to determine the age of primitive magma trapped within rocks. The results strengthen a controversial study previously published by the same scientific team in 2008.
"This volcanic rock is at least 4.16 billion years old or older; in my opinion, its best age is 4.3 billion years," said Jonathan O'Neil, an environmental science professor from the University of Ottawa, as quoted in the article report. Live Science on Saturday, June 28, 2025.
According to the professor who is also the author of the study, no other rock formations are known to be older than this discovery. Therefore, these rock formations are considered able to provide a unique insight into the early history of Earth and the chemical conditions where life first appeared.
As described in the article, the Earth initially formed as a hot ball of lava that gradually cooled over the first 600 million years, a period known as the Hadean eon. During this time, pockets of solid rock began to form, although the planet was frequently struck by asteroids and experienced major collisions, such as with the protoplanet Theia, which resulted in the formation of the Moon.
Around 3.8 billion years ago, the Earth's surface began to break up into tectonic plate Those that continue to move and create mountains and ocean trenches. The subduction process causes most of the rocks on the Earth's surface to have undergone chemical changes due to heat and pressure.
However, some regions far from tectonic plate boundaries—including northeastern Canada—still retain rocks that have remained relatively unchanged for billions of years. The NGB is part of this region, and scientists agree that the rocks at this location are at least 3.8 billion years old.
In 2008, O'Neil and her team claimed that the age of the rocks in NGB reached 4.3 billion years. However, this claim faced criticism because the volcanic rocks in NGB do not contain zircon minerals, which are commonly used for dating due to their long-term stability. Instead, at that time, the team used the samarium-to-neodymium decay method.
The method caused debate because samarium can decay through two paths: samarium-146 to neodymium-142, and samarium-147 to neodymium-143. These two paths have different half-lives, resulting in age estimates considered inconsistent.
However, O'Neil argued that any 'heating' or rock metamorphism after 4 billion years ago would not significantly affect short-term decaying clocks. "But it can reset the long-term decay clocks and cause differences in age between the two systems."
Nevertheless, to address this uncertainty, the team returned to the site and searched for sections of rock that had been intruded by magma from the Earth's mantle. Theoretically, this magma must be younger than the rock it penetrated, so this section can serve as a minimum age reference. The latest analysis shows that in this area, both samarium decay pathways provide consistent age results, which is 4.16 billion years.
"Some rocks from the Nuvvuagittuq Greenstone Belt were formed from seawater precipitation, and this could help us understand the composition of our first ocean, its temperature, possibly its atmosphere, and even where traces of the oldest life on Earth might be found," O'Neil said.
She added, "Understanding the environment where life first appeared on our planet also helps in our search for signs of life elsewhere, such as on Mars."
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