In 2002, Maximiliano Rocca learned that near the Falkland Islands there was a circular anomaly with large underwater proportions. One day that year, he came across a paper published by geologist Michael Rampino, a researcher at New York University, who in the early 1990s suggested the possibility that this anomaly was actually an impact crater. .
Rocca is a systems analyst and dedicates part of his free time to his love of geology, a career that began but never ended. When he read the article he was very impressed. He was more surprised when he searched the internet and found nothing about the problem. Rampino’s work was very interesting, but short, he did not study this basin in depth. “No one seemed to have repeated this work. I decided that I would be the one who would properly investigate this place,” Rocca said in dialogue with infobae.
The first thing he found was a Malvinas gravity anomaly map from the Argentine Mining Geological Service (SEGEMAR) dating back to 1997. It showed a tremendous circular structure in the northwest of the Great Malvinas, near the islands.
As a second step, he contacted British geologists who are experts in the Falklands. At first, he found tension, little willingness to cooperate. Until now, the English had hardly paid attention to the underwater geology surrounding the islands. In one of the few papers, the authors acknowledged that there was something mysterious, unexplained, in the northwest. That’s where they located the basin and that’s where they added a question mark.
After a few months, they agreed to share data from the area. By 2004, Rocca had so-called gravity anomaly maps showing a large crater 250 kilometers in diameter. He had a first clue that confirmed his assumption, but he needed more information, he asked for other types of maps, the magnetic ones, which he could not find until ten years had passed.
In 2015 he met Paraguayan geologist Jaime Báez Presser, an expert in impact craters, and asked him if he could map the magnetic anomalies of the Malvinas. In just a few days, it gave him access to a global database of magnetic maps, which he didn’t even know existed. Again, on these maps there was a positive anomaly now in magnetic values, consistent with his theory.
-I remember when I saw Jaime’s cards I thought: “I can’t believe it…this fits the bill for a colossal impact crater” he commented. The northwestern Malvinas structure is almost a replica of the Chicxulub crater in Yucatan, Mexico, 200 kilometers in diameter and also covered by smaller sediments. It was the impact that killed the dinosaurs 66 million years ago.
With this information in hand, he wrote his first scientific article on the subject, with Báez Presser as co-author. It was published in Maimonides University’s Natural History in 2015. After that first paper, he contacted Rampino, the original discoverer of the basin, and updated him on the progress of the research. They worked together and in 2017 published a new report in the Oxford journal Terra Nova.
“It was very important because we published in one of the best geology journals in the world and in England, no less,” Rocca remembers. The publication brought consequences in the scientific community, including in the press. Penguin News, the only newspaper published in the Falkland Islands, echoed the finding.
At this time, infobae told the story of what could be a discovery that would rewrite part of geological history: a large crater was created about 250 million years ago whose impact could have caused a mass extinction.
A few years passed, and since then, there have been some advances in research. Rocca met another geologist, Dietmar Müller, from the University of Sydney, who shared with him the best map of gravity anomalies in the area. “This map is for geology as x-rays are for doctors,” said the Argentine researcher.
-What do you see there?
“It shows us what is hidden under the water and under the ground around the islands,” he replied. It is a large circular structure 250 km wide in the shape of a soup plate. What in geology is called a basin and has all the characteristics of an asteroid or a comet impact crater.
– Why did the British geologists not recognize it at the time?
-They realized that there was a strange “basin” in this place, but what they did not notice is that it could be what is technically called an “impact basin” in geology. That is, a basin formed by the impact of a cosmic object. This seems just a play on words, but it is reality.
– Let’s say it’s not just another bath…
– Not at all. This underwater basin, covered by smaller sediments, is not a common and wild basin, but something unique in the area and in the world … a large impact crater.
The crater is only visible on geophysical maps. There is no stone where it can be associated, which is logical given the age of the basin. The impact would have occurred about 250 million years ago.
As Rocca explains, the tub has Two features that fit well with an asteroid or comet impact crater:
1) It shows a ring of positive gravity values 250 kilometers in diameter, surrounding a center of negative values. This pattern is typical of impact craters of colossal size and is even repeated in craters on the Moon and Mars.
2) It shows a tremendous positive anomaly in the magnetic field, which the researcher called “Rosa de las Malvinas”, due to the color that is usually used on the maps to draw the maximum magnetic value.
“When we put these two things together in the same place and associate them with a crater-shaped basin, the logical conclusion we reach is an impact crater. It is the simplest explanation,” he added.
A few years ago, Rocca considered the impact of an asteroid as the leading hypothesis. Today he chooses instead to commit. Asteroids are made of rock, mostly silicates and iron. They have neither ice nor gas. Instead, comet nuclei are rich in helium-3 gas, composed of ice and carbon dioxide.
A recent investigation by Japanese scientists reported the discovery of the extraterrestrial gas helium-3 252 million years ago, around the end of the geological period called the Permian, in Japan. “It tells us that something put all this foreign gas at this time in history. And the easiest way to explain it is that a comet hit the Earth.” warned Rocca, who clarified that for now the hypothesis is speculative, with more work needed to prove it.
His hypothesis establishes that a comet nucleus more than 10 kilometers wide could have impacted 252 million years ago in the Malvinas, which would have coincided with the worst mass extinction in history, with the extinction of 90% of marine species and 70% in terrestrial species. of the planet, and the event is called “great death”.
To account for the magnitude of the event, he drew a comparison. The energy, in these cases, is measured in a unit called megatons of TNT. Each megaton is equivalent to one million tons of the explosive trinitrotoluene (TNT).
An atomic ballistic missile, which would be a nuclear weapon, has a power of 10 megatons of TNT. This value would be enough to devastate a city the size of Buenos Aires. Now, when it comes to the impact of a comet, in a cosmic object moving at 30 kilometers per second, like the one that formed the Chicxulub crater in Yucatan, it gives a total of 100 million megatons of TNT.
-Yes, a hundred million megatons of TNT Rocca repeated. This represents a magnitude 12 earthquake, the most powerful earthquake ever recorded in history. Well… the possible impact on the Malvinas would release a similar energy.
As soon as the article was published in the Oxford magazine, the basin that lies next to the Falkland Islands gained more notoriety. Although Maximiliano Rocca has made some progress since then, he has never received enough support from English geologists who, according to him, choose to remain silent because the only possible explanation, with the available data, is that of a crater impact.
The major obstacle he encountered was that, in order to make a detailed study of the site, he would need to drill where the crater is and, in this way, obtain rock samples. It just so happened that the procedure would cost millions of dollars.
“To study it well and in depth, you should go with an oil drilling ship. You should stop just above the crater and drill a few hundred meters to get rock samples from the crater site itself. The English don’t even want to talk about it. That’s why the problem is paralyzed,” Rocca warned.
Meanwhile, a find that could shed light on the end of the Paleozoic era, more than 250 million years ago, is kept in the dark, hidden under the sea.
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