Oldest Rocks on Earth Found 4.28 Billion Years of Age
Scientists have discovered rocks that until now believed to be the oldest rocks on Earth. Age of 4.28 billion years old makes the stone more than the 250 million year old rocks were found previously.
According to scientific calculations, the Earth formed about 4.6 billion years ago from a disk of dust and gas that surrounds the sun. But the remnants of Earth's infancy are hard to find because most of the material is recycled by the Earth due to abdominal movement of tectonic plates that constantly change the Earth's surface.
In 2001, geologists found a stone slab known as Nuvvuagittuq green belt on the east coast of Hudson Bay in northern Quebec. Suspect that the rocks there may have originated from the early period of Earth's history, geologists took samples to determine their age.
They measure small variations of isotopes of rare earth elements, neodymium and samarium in the rocks and determined that the samples were from 3.8 to 4.28 billion years.
The age of the oldest, dating from the stone called "faux amphibolite", believed to be ancient volcanic sediment. This stone beat the previously oldest known rocks, with 4.03 billion years old and came from a formation called Acasta Gneiss, Northwest Territories Canada.
The only starting material older than Nuvvuagittuq stone is zircon from isolated mineral grains that are resistant to weathering and geological processes. The oldest zircons from the grains in Western Australia approximately 4.36 billion years old.
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