Researchers Discuss Implications of Pacific Ocean Tectonic Plate Changes
Tectonic plates are the thinnest outer layer of the planet, they float on magma, are divided into oceanic and continental crust and fit together like a puzzle. They are related to the formation of continents and oceans and their movements are responsible for generating volcanoes, earthquakes and tsunamis.
Researchers at the University of Toronto discovered geological faults in the Pacific Ocean Plate, which together are thousands of meters deep and hundreds of kilometers long and are fragmenting the plate — it was known that there was only one below the Pacific. However, more studies are needed to prove this thesis that the plates are less solid than was understood by the scientific community, since the presence of these fissures was only proven at the edges of the crusts, not inside them.
What is this failure and what are the risks?
The faults found by the researchers are aspects in the rocks, generated by tectonic efforts, which appear as marks, sometimes visible, and can be associated with the deformation or movement of large blocks of earth. In this sense, Professor Marcelo Bianchi, from the Department of Geophysics at the Institute of Astronomy, Geophysics and Atmospheric Sciences (IAG) at USP, says that its length, depth and orientation can say a lot about the environment it finds itself in and the types of forces that act on the ground: “ The discoveries presented are part of the evolution of our planet, which, unlike other bodies, has active plate tectonics and should contribute to increasing knowledge of the dynamics of the ocean floor”.
The article deals with a relatively small zone of intense seismic activity — consumption, generation and shock of plates and volcanism — in which a part of the plate is being consumed by a subduction process, in which the entire plateau is being dragged back and the blocks “go down and up”. In this way, a series of failures are generated, the plate heats up, making it thinner and, consequently, the speed at which it is consumed increases.
However, the professor at the Institute of Oceanography (IO) at the University of São Paulo (USP), Felipe Toledo, highlights: “All this is happening in terms of geological times, that is, if you think ‘what will happen in human terms ?’ Anything. What we can feel are earthquakes or some volcanic activity, but we will not witness major changes or geological deformations.” From this, he guarantees that, knowing the current configuration of the continents and their history, it is possible to simulate what the new continental configuration will be like .
He also addresses that the greatest risk caused by the emergence of these faults is linked to the thinning of the crust at the traction point, as it will allow magma to rise to the ocean floor — the “ocean floor”, around four thousand meters below the water. — and, consequently, increase the separation speed, which will be resisted at the ends by areas of plate consumption.
From another point of view, Luigi Jovane, professor at IOUSP, comments: “These areas have no population or buildings, so the risk is very low. But the problem is that they will probably generate large tsunamis, which will spread across the entire oceans, and certainly across the Pacific, generating gigantic waves.”
Changes in the panorama of the scientific community
In view of this, Toledo states that this new discovery will provide a movement of countries with greater conditions to invest in research on this scale of importance and proportion, after all, these are very extensive areas. On the contrary, according to him, Brazil is far from having funding for studies of this size.
On the other hand, Jovane explains that the scientific community was already aware of the fact that the oceanic crust ages and sinks — as it becomes heavier — and, from the moment it submerges, its surface part is loaded. “ This is a fundamentally new process in plate theory, which has been known for several years. Now, they have detected that this force allows for an extension in this plateau area, which is more fragile, and which generates these faults”, he explains.
Furthermore, Bianchi adds that, currently, there is a distinction between the processes that take place in the oceanic and continental lithosphere and that this recent discovery, of deformation in the maritime crust far from the edges, was difficult to explain. He comments: “ Once we have a model for such deformations, this will allow us to better understand processes such as tectonism, seismicity and other oceanic features not yet fully explained by plate tectonics.”