A group of Canadian scientists is redefining the centuries-old theory of plate tectonics. Until now it was believed that the plates covering the ocean floors are rigid as they move across the Earth's command. However, researchers from the University of Toronto have discovered that the plate is marked by large underwater faults that separate it, as described in an article published by the journal Geophysical Research Letters.
Some of these faults would be thousands of kilometers deep and hundreds of kilometers long, the result of enormous forces within the plate that are pushing it westward. “We knew that geological deformations such as faults occur inside continental plates, but we did not know that the same thing was happening with oceanic plates,” says Erkan Gün, postdoctoral researcher, in a statement released by the University of Toronto.
The researchers studied four plateaus in the western Pacific Ocean—Ontong Java, Shatsky, Hess and Manihiki—between Hawaii, Japan, Australia and New Zealand based on supercomputing models and literature data from some research conducted in the 1970s and 1980s. From observing seismic activity, they concluded that oceanic plateaus are the weakest part of the plates, with a tendency to tear, forming faults. This fact has caused the plate at the bottom of the Pacific Ocean to move westward for millions of years until it sank into the Earth's mantle or along underwater trenches or subduction zones.
On the other hand, there is evidence that volcanism occurred at these sites in the past as a result of this type of plate damage, sporadically or continuously, but it is not clear that it is happening now. Scientists hope that this article will draw attention to the plateaus and continue research, since, Gün argues, “the plateaus are thousands of meters below the ocean surface and sending ships to collect data is an important economic inversion".
Although it is not the first time that research provides new insights into the theory of plate tectonics, professor of the Department of Earth Sciences, Russell Pysklywec, states that this finding confirms that the functioning of our planet still hides many mysteries to discover. “The theory is not written in stone and we now know that the damage from this fault is tearing the center of an oceanic plate, and this could be related to seismic activity and volcanism,” concludes the researcher.
