Indian tectonic plate is breaking into two. It’s happening beneath Tibet

In a new discovery that could reshape our understanding of the forces shaping the Earth’s highest mountains, researchers have unveiled new seismic data indicating that the Indian tectonic plate is splitting in two beneath the Tibetan plateau.

This revelation was presented at the American Geophysical Union conference in San Francisco and offers a fresh perspective on the colossal Himalayan mountain range’s formation.

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For decades, geologists have known that the Himalayas owe their towering presence to the collision of the Indian and Eurasian continental plates. This process, which began around 60 million years ago, has been likened to the crumpling of a car’s hood in a head-on collision, with the Indian plate being driven beneath its northern neighbor by the currents of molten rock within the Earth’s mantle.

Over time, this tectonic interaction has thrust the Eurasian land mass skyward, creating the planet’s highest elevations.

However, the latest analysis challenges previous assumptions about the subduction of the buoyant Indian plate. Rather than sinking smoothly into the mantle’s depths, the seismic data suggests a more complex scenario where the plate is delaminating.

The dense base of the Indian plate is peeling away and descending into the mantle, while its lighter top portion continues to scrape just beneath the Eurasian plate.

This new model of tectonic activity was pieced together by a team led by Ocean University of China geophysicist Lin Liu. By combining ‘up-and-down’ S-wave and shear-wave splitting data from 94 broadband seismic stations across southern Tibet with ‘back-and-forth’ P-wave data, the researchers have provided a nuanced view of the subterranean dynamics at play.

The findings indicate that the Indian slab is neither gliding along nor crumpling uniformly but is undergoing a dramatic structural separation. Some sections of the plate appear relatively intact, while others are fragmenting approximately 100 kilometers below the surface, allowing the base to deform into the Earth’s fiery core.

This seismic investigation aligns with geological models based on helium-3 enriched spring water and patterns of fractures and earthquakes near the surface. Together, these pieces of evidence paint a picture of tectonic turmoil deep beneath the Himalayas.

The implications of this study are profound, not only for our understanding of mountain formation but also for earthquake prediction methods. With a clearer three-dimensional image of how tectonic plates interact, scientists can better comprehend the Earth’s surface evolution and potentially forecast seismic events with greater accuracy.