If we only focus on what is seemingly visible, the Himalayas stand as an immutable, intact, majestic figure with millions of years of history. However, if we look a little further, science tells us that something is happening beneath its surface, as research indicates that the Indian plate located under Tibet is tearing apart. To understand the origin of the Himalayas, we have to go back 60 million years, when India was just an island that collided with the Eurasian plate.
The interesting thing about all this is that the plate has not stopped moving, so scientists are faced with two hypotheses: either the plate will only slide horizontally beneath Tibet, or the denser part of it is sinking into the Earth’s mantle. However, reality shows that the Indian plate is splitting into two.While the upper layer continues sliding beneath Tibet, the lower layer is delaminating: it is separating and sinking into the mantle.
This conclusion was made possible thanks to the research of Dan Klemperer and his team, the study of seismic waves, and the history of the plate. Anne Meltzer, a seismologist at Lehigh University, explains that it is important to understand how continents collide, as this is the origin of all the Earth’s landmasses. An example of tearing is the fault known as the Cona-Sangri rift, and although there is still no evidence, geologists believe that this continental collision and tectonic fracturing could trigger earthquakes.
Himalayas
What at first glance seems like an invincible, static, and majestic structure is nothing more than the perception we get of the Himalayas when we look at them. The truth is that if we look more closely, geology explains what is happening beneath Tibet, which has nothing to do with what it appears. To understand the origin of the Himalayas, we must go back 60 million years when India was just an island.
It was then that it collided with the Eurasian plate, causing the crust to fold and creating the highest mountains on the planet. The curious thing about this process is that this movement has not yet stopped. There are two main hypotheses on which geologists base the direction the plate is taking:
- One argued that the plate simply slid horizontally beneath Tibet, like a rug being pushed under a sofa.
- The other argued that the denser part was sinking directly into the mantle, the Earth’s deepest layer.
What is really happening beneath Tibet?
Despite these hypotheses, a new study has revealed that none of them explains what is happening. According to the data, the Indian plate is splitting into two layers: the lighter, less dense upper layer continues its path sliding beneath Tibet, while the lower one is separating and sinking into the Earth’s mantle, that is, it is delaminating. In addition, they have been able to show that the portion that is separating as a vertical fracture remains intact.
How did they reach this new conclusion?
The scientists tested this new theory in three aspects: Klemperer and his team found the presence of helium-3 in more than 200 natural springs. This drew attention because it is an isotope that can only come from the Earth’s mantle. The separation of the lower part of the plate has also been demonstrated thanks to data collected from the seismic Honda, which has shown images of underground blocks.
Based on the history of the plate, scientists claim that it could occur, producing a real-time division, since the Indian plate has regions with different thicknesses, so it behaves differently when coming into contact with Eurasia.
Possible earthquakes
According to seismologist Anne Meltzer from Lehigh University, “Almost all of Earth’s landmasses were built from a series of collisions like the Himalayas. Therefore, understanding how continents collide sheds light not only on our modern landscape but also on the hazards posed by earthquakes that may occur along the ancient scars of continental collisions.” That is why geology suggests the possibility that these ruptures could trigger seismic movements, although there is still no evidence of this.