Scientists have discovered world’s second oldest grain of magmatic zircon (a mineral that contains traces of radioactive isotopes) from Champua from Singhbhum rock sample in Odisha’s Kendujhar district. It is an estimated 4,240 million years old, making it world’s second oldest rock ever to be discovered. It is oldest magmatic zircon on earth.
The isotopic analysis of Singhbhum rock sample with magmatic zircon was done used Sensitive High Resolution Ion Microprobe (SHRIMP) at the Chinese Academy of Geological Sciences, Beijing, China. The analyses confirmed the presence of two zircon grains that were 4,240 million and 4,030 million years old. The oldest zircon older than this discovery was found in Jack Hill, Western Australia. It is 4,400 million years old and is the oldest known rock sample. It is metamorphosed sedimentary rock.
This rock sample was recovered nearly eight years ago and has put India at the forefront of geological research in the world. This discovery of great promise to study the earth’s early years. It will also add valuable information about presence of water in the first few hundred million years of Earth’s history. It will also give us clues to when plate tectonics began.