The world is a mysterious oyster that holds within itself unimaginable secrets. Scientists and researchers hold the key to many of our planet’s evolutionary enigmas. Of all this, how beaches and landmasses began to take shape, has always been an evolving puzzle. Now, a study published in the Proceedings of the National Academy of Sciences by a team of Indian, Australian and South African scientists has discovered that the first continents on Earth were formed about 3.2 billion years ago. This is in contradiction to earlier studies which revealed proof of continents emerging 2.5 billion years back. And the most fascinating part? Researchers claim that evidence points towards the world’s first beach arising out of Jharkhand’s Singhbhum district. Priyadarshi Chowdhury, the lead scientist of the research, from Australia’s Monash University, studied the sedimentary rocks of Singhbhum ‘craton’ (continent). The team also dated Earth’s most ancient rocks thought to have risen from the first-ever beaches, by analysing fragments of India, Australia, and South Africa.
From the chemical structure of zircon grains in the ancient rocks, the scientists realised that it was 3.1 billion years old and emerged from rivers and oceans. The water bodies can exist only in the presence of continental land. They concluded that the Singhbhum craton of Jharkhand had first come above sea level approximately 3.3 billion to 3.2 billion years ago, assigning it the tag of possibly one of the most ancient beaches on Earth.
According to an Indian Express report, conclusive evidence was found in the form of sandstones at the Singhbhum region which had the geological bearings of ancient beaches dating back to 3.2 billion years. According to the study, the widely held belief that plate tectonics led to landmass formation is negated in this particular region as it is believed that the injection of magma from the depths of the Earth led to the creation of the first continents.
The scientists wrote in the study, “Although debated, the broad consensus is that the subaerial rise of continents began nearly 2.5 billion years ago and was driven by plate tectonics. Here, we integrate the igneous and sedimentary history of Archean cratons to demonstrate that stable continental landmasses started to emerge above sea level 3.3 to 3.2 billion years ago (i.e., over 700 million years earlier than most models predict).”
The revolutionary study shows that continents came into being 700 million years earlier than believed, giving more context to the relation of Earth to the atmosphere and oceans, which is especially important in the age of critical climate change.