This is the first time this behaviour has been observed in an actual descending tectonic plate.
India, the world’s seventh-largest country, is undergoing a profound physical transformation. A recent study reveals that the Indian Continental Plate is in the process of splitting horizontally into layers, much like a flaky pastry coming apart.
Throughout history, scientists have debated the origins of the majestic Tibetan Plateau. At a December conference of the American Geophysical Union, a novel theory emerged: the Indian Plate is ‘delaminating.’ This means that the upper layer of the plate is pushing upwards, contributing to Tibet’s soaring elevation, while the lower layer is gradually descending into the Earth’s mantle.
Simon Klemperer and his team at Stanford University made this discovery by analyzing helium levels in Tibet’s natural springs. Their research identified patterns suggesting that the Earth’s mantle is closer to the surface than previously thought, allowing rare helium-3 to escape through these springs in northern Tibet.
The study elaborates: ‘Our SRFs objectively map depths to distinct Indian and Tibetan lithosphere-asthenosphere boundaries across a substantial region of southeastern Tibet. The inferred boundary between the two lithospheres is corroborated by more subjective mapping of changing SWS parameters and independent interpretations of mantle suture patterns and sub-Moho earthquakes.’ Essentially, this means that the Indian Plate is not splitting but rather peeling into layers.
Interestingly, the research indicates that southern Tibet shows higher levels of helium-4, suggesting the plate has not yet split in that region.
Professor Douwe van Hinsbergen from Utrecht University, who did not participate in the study, mentioned to Science Magazine, ‘We didn’t know continents could behave this way, and for solid earth science, this is pretty fundamental.’
The study has not yet undergone peer review, but Fabio Capitanio, a geodynamicist at Monash University, emphasized that this research serves merely as a starting point: ‘It’s just a snapshot. It’s definitely the type of work that we need to move forward.’
While scientists have previously studied and simulated such phenomena with computer models, this study marks the first observation of this behavior in an actual descending tectonic plate.