NEW DELHI: An international team of researchers has found a “lost” river that flowed through the central Thar desert, near Bikaner, 1.72,000 years ago. The river likely served as a lifeline for Stone Age populations, helping them thrive in what is now an arid region, while also serving as an important corridor for human migration, according to research representing the oldest phase. of river activity dated directly in the Thar. region.
The new findings, published online in the journal ‘Quaternary Science Reviews’ ahead of print, set back previous evidence for river activity at Thar by as much as 80,000 years. Researchers from Germany’s Max Planck Institute for the Science of Human History (MPI-SHH), Anna University (Chennai) and the Indian Institute of Science, Education and Research (IISER) in Kolkata studied sand and gravel deposits from rivers exposed by mining activity near Nal village, outside of Bikaner, in 2014 and 2019.
“The key method we use is luminescence dating that allows us to calculate the age at which the grains of quartz in the river sands they were last exposed to light, ”MPI-SHH’s James Blinkhorn told TOI.
“The oldest and well-dated evidence of river activity in the Thar comes from the luni valley, which was active 80,00090,000 years ago, with comparable evidence farther south in the Mahi, Sabarmati and Orsang valleys, where similar evidence of river activity dates back 100,000 years, ”said Blinkhorn.
According to Hema Achyuthan, professor at Anna University Institute of Ocean Management: “Thar may be a desert now, but there are several paleo channels, where rivers would have flown once, in the region that are buried by sand dunes. In certain places, like Nal, the gravel deposits are exposed and that helped us directly date one of those river systems for the first time. ”
.
