An international team of researchers has identified what they claim could correspond to the first evidence of the detachment of the lower part of a tectonic plate, a phenomenon specified in theory but never previously detected by geology.
Earth’s Crust Peeling into Two
Tragically, in 1969, a massive earthquake off the coast of Portugal gave rise to a massive tsunami that created chaos and destruction. Some 200 years before that, on the 1st of November 1755, a giant 8.7 magnitude earthquake struck off the coast of Portugal, destroying the city of Lisbon.
Two Earthquakes occurring in around 200 years is not something alarming, but it is worrying when seismologist found that the earthquakes occurred in a relatively flat abyssal region, far from any known tectonic faults with significant length and surface expression.
The idea is that the Earth’s crust could be peeling into two. In other words, the top part of the crust may be peeling off the bottom layer.
And while this phenomenon has never before been observed, a group of researchers reported in April at the European Geosciences Union General Assembly held in Vienna how the peeling of the crus may give rise to a new subduction zone, an area in which one tectonic plate is driven beneath a different one.
The Atlantic Ocean Could Disappear
João C. Duarte, from the University of Lisbon, had previously concluded together with other experts that an anomaly in that same area could cause the European continent to move towards Canada reducing the size of the Atlantic Ocean.
Now, Duarte leads a study that has been given the task of studying data collected in recent years to clarify what happens at the site.
Duarte and his team analyzed a previous scan of the Eurasian tectonic plate.
The data had suggested that one part of the lithosphere began to sink under another in what was suspected to be the birth of a subduction zone, something never before witnessed in geology.
Duarte and his team linked these results with other results obtained int he past, which pointed to the fact that ocean water currently seeps to the bottom of the plate through a network of fractures in it, and while doing so, it softens the minerals of the lithosphere in a process known as serpentinization.
Now, this modified layer might be inducing enough weakness in the plate for the lower layer to peel away from the top layer.
That peeling could lead to deep cracks that trigger a tiny subduction zone, the National Geographic reported.
And while this paper isn’t the first to propose such an idea, it is the first time we actually see the theory backed up by solid data.
It is noteworthy to mention that the study has still not been published in a peer-reviewed journal.