A groundbreaking discovery for science, as researchers uncovered 4.5-billion-year-old rocks. These ancient rocks date back to almost the time of Earth’s formation, some 4.5 billion years ago. The rocks are located in the mantle of the Earth and have formed during the primitive era.
The discovery was made by a team of researchers from the U.S. and Canada. The silicate material formed within two volcanic rocks, distant from each other. One layer was found in Ontong Java Plateau in the Pacific Ocean and the second layer remained in a rocky formation in the Baffin Bay in the North Atlantic.
These rocks are named flood basalts, as they were created through lava eruptions. The solidified lava is 60 to 120 million years old. Researchers, however, discovered that the molten material inside our planet owes its composition to events that have happened 4.5 billion years ago.
Scientists believe that the Earth grew to its current size through the accumulation of material from collisions with asteroids and other celestial bodies, over a period of millions of years. Scientists used to be skeptical of the idea that any vestiges from the earliest period of the Earth could have survived. This began to change in 2012 when researchers discovered clues that material from the mantle existed until almost 3 billion years ago.
The team’s findings were based on the detection of an overabundance of hafnium. Hafnium is an isotope of tungsten. Tungsten -182 was present during the formation of the solar system. However, it is no longer found on this planet. It was a real surprise for the team of experts to find that hafnium still exists in the mantle of our planet. It was previously believed that the residues of crust formation had mixed back into the mantle, and all evidence of the Earth’s oldest geological events had been lost.
Ratios of radioactive isotopes can provide a record of the events that took place a long time ago, at the birth of our planet. By finding such materials, researchers uncovered 4.5-billion-year-old rocks that no one believed to still exist. In the future, scientists will have to continue to search for areas high in tungsten-182 to unravel more of the Earth’s earliest history.
IMAGE SOURCE: Wikipedia