Researcher says Earth's crust could take off at two coasts of Portugal

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Scientists have discovered that a tectonic plate off the Portuguese coast could split into two layers.

In 1969, an earthquake caused a tsunami. 200 years ago, an earthquake of magnitude 8.7 had struck the region, destroying the capital, Lisbon and killing 100,000, according to Joao Duarte, marine geologist of the Lu Lu Institute. At the University of Lisbon .

Because of these two earthquakes, scientists have trouble understanding why, because they did not occur near any cracks or fissures in the earth's crust.

Some scientists have speculated that the crust in this zone could break down into two layers, creating a new zone of subduction, that is, when one tectonic plate is sunk under another, according to a summary of their results.

"If they are confirmed, the new work would be the first takeover of an ocean plate being peeled off – and could mark one of the first steps in the contraction of the Atlantic Ocean. , projecting Europe to Canada, as predicted by some models of tectonic activity, "said National Geographic.

Fabio Crameri, from the University of Oslo, said that although "it's certainly an interesting story," the hypothesis has yet to be verified.

"It's a big statement," said Duarte. "Maybe that's not the solution to all the problems. But I think we have something new here. He added that it was not clear how the subduction zones were starting, it's an unresolved problem.

About 90% of earthquakes worldwide occur in the Pacific Fire Belt, which extends from New Zealand to the southern tip of South America and encompasses Indonesia, Japan, Alaska, the west coast of the United States. United States and more.

Around the Atlantic Ocean, however, the tectonic plates separate and form a new crust.

National Geographic noted that the 1969 earthquake hit a relatively flat area below the surface of the ocean.

"It's like a Kansas plain less than 3 miles [three miles] Marc-André Gutscher, geologist at the French University of Western Brittany, said at the exit.

In 2018, a researcher from the Instituto Dom Luiz of the University of Lisbon published a high resolution image of the region, showing signs of activity.

"Now we are 100% sure that it is there," Duarte told the branch.

Live Science pointed out that Duarte and his team were not the first to propose this idea, adding that it had not yet been published in a peer-reviewed journal.

Earthquake of 1755

In 1755, an earthquake known as the "Great Lisbon Earthquake" occurred off the coast of the city, causing a series of fires and a tsunami that killed tens of thousands of people.

The location of the earthquake (USGS)

"This earthquake took place on All Saints' Day when many of Lisbon's 250,000 people were in church. The stone buildings swayed violently and collapsed on the population. Many of the people who sought safety on the river were drowned in a tsunami. The fire ravaged the city. A quarter of the population of Lisbon perished. This earthquake has had a profound impact on the intellectual prospects of Europe, "said the US Geological Survey.

At the time, a number of Enlightenment philosophers discussed the event, according to the New World Encyclopedia.

"Thanks to a stroke of luck, the royal family escaped unscathed from the disaster. King Joseph I of Portugal and the court had left the city after attending mass at sunrise, thus fulfilling the wish of one of the king's daughters to spend their holidays away from Lisbon. After the disaster, Joseph I was afraid to live inside the walls and the courtyard was installed in a vast set of tents and pavilions on the hills of Ajuda, then on the outskirts of Lisbon. explains the statement.

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