There is hardly a mountain as majestic as the Himalayas, which rise so high in the sky that man feels like a dot standing in front of him. However, what is less known is that the Himalayas are not only picturesque but also an area considered significant for the study of geology. A 2023 study in this region suggested that the Indian tectonic plate, which makes up part of the Himalayan floor, could break into two parts. The reason for this is that the plates beneath the Himalayas undergo a bizarre process.
The Great Himalayan mountain range stretches upward in steep, jagged formations and consists of hundreds of peaks, with Mount Everest reaching a height of 29,035 feet. It was first formed 40 to 50 million years ago when the Indian Plate collided with the Eurasian Plate, deforming the surface and creating the world’s tallest mountain. Since both plates were the same thickness, they did not collide but clumped together, creating colossal rock structures.
A geologist from Stanford University, Simon L. Klemperer, and some of his geodynamics colleagues went to the Himalayan zone in Bhutan to investigate. There they examined the helium content of Tibetan springs. Although the Himalayas are a treasure trove of elements such as gold and silver, the presence of helium, especially in inappropriate quantities, suggested the possibility of a dormant volcano hiding somewhere beneath.
The study was conducted taking into account two previous theories. One theory suggested that the Indian plate collided horizontally with the Eurasian plate, while the second theory suggested that the Indian plate submerged beneath the Eurasian plate, melted into magma and spewed out helium. The study found that helium levels were higher in southern Tibet than in northern Tibet. From this, Klemperer concluded that the Indian tectonic plate split into two fragments beneath the Tibetan Plateau in a process known as “delamination.”
Klemperer considered both theories and proposed a third theory, saying that the processes mentioned in the first two theories occurred simultaneously. While the upper part of the Indian plate rubbed against the Eurasian plate, the lower part of the Indian plate diverged (subducted) into the Earth’s mantle. The researchers originally presented their findings at the American Geophysical Union conference in December 2023. “We didn’t know that continents could behave like this, and that’s pretty fundamental to solid geology,” Douwe van Hinsbergen, a geodynamicist at Utrecht University, told Science.
For his study, Klemperer used a series of isotope instruments to measure helium bubble formation in the mountain springs. They collected samples from about 200 springs over a 621-mile stretch and found the sharp line where mantle rocks join crustal rocks. They discovered a group of three springs where the Indian Plate appeared to be peeling off like the two yellow peels of a banana.
The layers of a tectonic plate are built like a layer cake. The bottom layer is denser and thicker than the upper layers. However, when two plates collide, there is a chance that the weaker layers will give way and start to break. So scientists were aware before this research that tectonic plates can break apart in this way. However, this process has mainly been observed in thick continental plates and simulated in computer models. “This is the first time that … it has been caught red-handed in a down-sloping plate,” said van Hinsbergen.
This fluctuating configuration of tectonic plates poses a threat to the great mountain range and also poses the risk of unexpected earthquakes and tremors. Although the study provided valuable data, the results showed the dance of contradictory natural forces with each other.