A NEW STUDY PRESENTED DURING THEAMERICAN GEOGPHYSICAL UNION IN SAN FRANCISCO HE REVEALED THE MYSTERY OF THE HIDDEN FORCES THAT CONTINUE TO SHAP OUR PLANET
According to the results of the research, the Indian plate, unlike others, such as the East African plate (which divides on a fault line), is on the verge of splitting in two.
One part is heading to Eurasia, the other is sinking beneath the Earth’s mantle.
If confirmed, this phenomenon could offer a fascinating key to understanding the formation of the Tibetan plateau and the majestic mountain range ofHimalaya. It could also help seismologists in forecasting earthquakes.
Orogeny, plate collision and delamination
The origin of the Alpine-Himalayan chain was a process of orogenic formation that began in the late Mesozoic (251 million years ago) and continued into the Cenozoic (over 65 million years ago).
L’orogeny, that is, the set of processes and phenomena of the formation of a mountainous relief, was caused by the closure of the Tethys Ocean, following the northward rise of Africa, Arabia and the Indian Subcontinent towards Eurasia. In practice, a collision between the Indian and Eurasian plates.
So far, nothing new. A new study conducted by scientists atOcean University of China in Qingdao, Shandong, adds interesting details.
The research results were explained during the last conference of theAmerican Geophysical Union in San Francisco last December.
For the occasion, the team presented new seismic data collected in Tibet southern and showed the rift of the Indian continental plate.
The detailed description, supported by advanced geological models, has painted a striking picture of the war between worlds underground.
But let’s get to the interesting demonstration and find out which theories were compared.
Three theories compared on the plaque
The starting point of the research suggests that theIndia is moving north at a speed of 1-2 millimeters per year, putting pressure on Eurasia that contributes to mountain uplift. A phenomenon that has lasted for 60 million years. But beyond these known data, the underground world of tectonic plates suggests something else.
Let’s see what scenarios the three different theories examined during the conference propose
The first suggests that, the plate indianaperhaps too light to sink into the cloak, could slip under the plate Eurasianlifting Tibet.
The second hypothesizes that the Indian plate could instead fold in on itself.
A third option, supported precisely by scientists from China University and the National Center for Environmental Forecasting Stanford UniversityCalifornia, instead proposes the thesis of “delamination”.
What are we talking about?
Delamination is a horizontal separation of the plate, a seismic event in all respects, with a denser part sinking into the mantle and another lighter one floating above.
The phenomenon occurs in practice when the lower continental crust and the lithosphere of the mantle detach from the upper continental crust.
But there’s more. The delamination offers a unique perspective on the complex seismic dance that shaped the Tibetan Plateau and the Himalayas.
According to the researchers, the secret of the continuous growth in height of the mountains depends precisely on these seismic forces which act as “invisible architects” underground.
The three-dimensional vision of the boundaries, the edges of the plates and the clash between them confirmed the suspicion. Clues that not only provide a clear understanding of the evolution of our Earth’s surface and seismic dynamics, but which could help seismology in earthquake prediction. Further evidence revealed very intriguing details.
Fundamental clues to support the research
One of the key clues that emerged from the research is the presence of bubbles elio-3 that emerge from the sources of Tibet.
It is useful to point out that theeliothe most abundant and widespread chemical element in the universe is very rare on Earth.
Helium-3, even rarer, originates only from the residues of the formation of our planet. It is rarely found in natural deposits. Which is why it is produced artificially.
Well, measuring the helium isotope ratios of 200 Tibetan springs showed a pattern of helium-3 leakage.
Simply put, the high concentration of this substance on the surface indicates a possible mantle origin.
Continuing south, it was found predominantly instead elio-4a light, non-radioactive isotope of helium.
According to scholars, its presence proves that in this area the plate has not yet split. In short, it would form a sort of barrier that prevents helium-3 from being released.
Another fascinating clue then emerged fromearthquake analysisi in the region.
The results suggested that the mantle is rising east of the Tibetan Plateau, causing the plates to continue to rise.
The litmus test
To explain the phenomenon, scientists compared the plates to the layers of a cake: the densest ones are at the bottom, thus preventing the intermediate layers from crushing. Likewise, the lower parts of the plates are made up of solidified igneous rock, denser than the upper parts.
Now, the fact that the Indian plate is thicker in the north and thinner on the sides supports the above theory, since the denser central part would sink faster even with a small pressure difference.
The research results were published in the journal ESS Open AQrchive