The Earth tilted on its side to compensate for a volcanic eruption

The Earth turned on its side to maintain balance * This is what scientists from several universities from Princeton, MIT, Caltech, and Harvard claim.

Avi Blizovsky

Imagine such a strong displacement in the depth of the Earth that could cause the entire planet to lie on its side after a few million years, until Alaska would lie on the equator. Princeton University scientists have provided the first evidence that such large-scale shifts have occurred in the distant history of the world.

By analyzing the magnetic composition of ancient sediments found in the remote Svalbard archipelago in Norway. Prof. Adam Maloof of Princeton reinforced a 140-year-old theory, much older than the theory of plate tectonics, according to which the Earth regains its balance, if an unequal distribution of weight develops within it or on its surface.

The theory known as true pole shift assumes that if an object of sufficient weight - such as a huge volcano - is formed far from the equator, the force of the Earth's rotation will cause the object to be pushed by changing the direction of the Earth's axis of rotation around itself. If volcanoes, continents, and other masses within the axis of rotation upset the balance, the planet will tilt on its side and rotate until the excess weight settles at a point on the equator.

"The findings we discovered in Norway provided us with the first good evidence that a real shift of the poles occurred about 800 million years ago," said Maloof, an assistant professor in the Department of Earth Sciences. "If we can get supporting evidence from other places on Earth, we'll have a good idea of ​​our planet's ability to make these kinds of dramatic changes."

Maloof's team, which includes researchers from Harvard, Caltech, MIT, and of course Princeton, published the study in the Journal of the Geological Society of America on Friday, August 25.

A real shift of the poles differs from the familiar idea of ​​"continental drift", a shift of a few centimeters per year of the Earth's continents relative to the other continents. The shift of the poles can turn the entire earth on its side at a rate of a few meters per year, between 10 and 100 times faster than the shift of the tectonic plates. Although the poles will continue to point in the same directions relative to the rest of the solar system, the process can move all the continents from the tropical region to the arctic region or vice versa, within a very short geological time.

While the idea that the continents move slowly relative to each other is familiar and known, the lesser known theory of polar drift was developed in the mid-19th century, several decades before the theory of continental drift was proposed.

However, when it was proven in the sixties of the 20th century that the continents move in accordance with the theory of plate tectonics, this provided proof for most of the dynamic processes on the surface of the earth, until the theory of polar shifts became an archaic and obscure subject.

Planetary scientists still talk about pole shift on other planets like Mars, where a huge mass of volcanic rocks has accumulated at sites called Tarsis on the Martian equator. "Since the Earth's surface changes frequently due to the movement of the tectonic plates on which the continents and oceans lie and these are pushed under each other, it is difficult to find evidence of the changes that our planet underwent hundreds of millions of years ago, as happened on Mars when it was geologically active.

However, the sediments that the team members studied in Svalbard from 1999 to 2005 may have provided evidence of this. It is known that when rock particles sink into the ocean they form layers of new sediment. Tiny magnetic cores inside the halo particles align themselves with the Earth's magnetic field lines. When the rock hardens, it becomes a reliable recorder of the direction of the magnetic field at the time of its formation. Thus if a rock has rotated due to a dramatic geological event, its magnetic field will point in an anomalous direction. Maloof's team looked for such rocks.

"We found several such anomalies in the sediments from Svalbard". Maloof said. "We made every effort to find another cause for these anomalies, such as a rapid rotation of the plate on which the island stands, but none of the alternatives made as much sense as true polar migration, even when the measurements were taken in the context of geochemical data and sea level data from the same rock.

According to him, the findings can also explain a rare change in the chemical composition of the oceans about 800 million years ago. Similar changes in the oceans occurred in ancient times, but in these cases scientists knew that ice ages were to blame.

Scientists have found no evidence of an ice age 800 million years ago, and the changes in the composition of the oceans during that time remain one of the greatest mysteries in the ancient history of our planet." said. However, if all the continents suddenly turned and their rivers started to flow water and nutrients to the tropical areas instead of the arctic areas for example, this could provide an explanation for these mysterious geochemical changes."

Since the researchers have acquired all their knowledge only from the Svarbard islands, Maloof says that the next high-priority step will be to find additional evidence in sediments of a similar age from other places on Earth. This is complicated, Maloof says, because most of the 800-million-year-old rocks are long gone. Because the tectonic plates move beneath each other, most of the geologic history is buried at great depth. However, according to him, his team found a promising area in Australia that contains rocks from that period.

"We cannot be sure of the validity of the findings until we find similar patterns in the chemistry and magnetism of rocks from other continents," said Maloof. "Rocks of the same age have been preserved in inland Australia. We will be able to visit the site over the next two years to look for more evidence. If we find such evidence, we will be more confident about the validity of the theory.

Maloof said that a true pole shift occurs when huge land masses converge to form a single supercontinent, something that has happened at least twice in the distant past. However, he says that there is no fear that such a shift will occur in the near future.

"If such an event occurred in the history of our planet, it was almost certainly when the continents were concentrated together on one side of the Earth. said. "We do not expect such an event in the foreseeable future. The surface of the earth is quite balanced today.

Maloof's research is funded in part by the National Science Foundation.

For information on the Princeton University website