“The changes and changes that have left the earth as we see it now, are not restricted to the beginning of the old levels” – Georges CuvierThe year 1831.
Our Earth has killed many parts of its population many times from the dawn of the beasts. And if science tells us anything, it’s definitely going to try to kill us all again. Working in the 19th century, the scientific pioneer science and technology) Georges Cuvier saw dramatic changes in life in the fossil record and compared them to the French Revolution, then still fresh in his memory.
Today, we refer to such events as “mass extinctions,” events in which many species of animals and plants die out. They are so deep and global that geological time is divided into periods—Permian, Triassic, Cretaceous—that are common. comment about these mass extinctions.
Debate on what caused these factory resets of the world has raged ever since Cuvier’s time. He considered them to be caused by environmental disaster that rearranges the oceans and continents. Since then, a host of explanations have been proposed, as well disease, galactic gamma rays, dark matterand also methane from microbes. But since the 1970s, many scientists have thought that the root cause may be either asteroid impactbig volcanic eruptionsor a total of both.
Those asteroid (or comet) impacts have captured everyone’s imagination ever since 1980, when Luis and Walter Alvarez found global traces of iridium, which they thought was extraterrestrial, at the edge of the earth that marked the extinction of the dinosaurs. Identification of the Chicxulub Crater impact in Mexico shortly after the deal was signed. Effects have been proposed to explain other large extinctions, but there is little real evidence to support those links. In the words of researchers David Bond and Stephen Grasby, who evidence review In 2016: “Despite many discoveries, there is only one confirmed example of a bolide impact that coincides with a nuclear event.”
Not just a random series of unfortunate events
Volcanism, on the other hand, has been associated with most, if not all, mass extinctions—it’s as suspicious as a serial killer, if you will.
This is not Vesuvius/St. Helens / Hawaii style volcanism. Not even big volcanoes like Yellowstone or Tambora. I’m talking about something far, far bigger: a rare, extraordinary volcano called a Great Igneous Zone or “LIP.”
LIPs are floods of basalt lava on an unimaginable scale: the Siberian Trap The LIP, which occurred in the end-Permian extinction, covered an area the size of Europe. You have decided that it is over 3 million cubic kilometers of rock they vomited onto the world’s surface, The end-Triassic Central Atlantic magmatic province, stretching from Canada to Brazil into Europe and West Africa, is as large. Others are equally gigantic.
In the words of Bond and Grasby, “Four of the ‘Big Five’ extinctions are associated with LIPs—most to be coincidental—implying that large volcanoes are the primary cause of mass extinctions.”
Also the extinction of the dinosaurs at the end of the Cretaceous is simultaneous with the Deccan Traps LIP in India. It is possible that total of the Chicxulub asteroid impact and the Deccan eruptions, rather than just impacting, pushed the planet over the edge. And soon the evidence points to it Reward trigger for the second phase of the end-Ordovician extinction, the one missing from Bond and Grasby’s quote. If confirmed, that would link LIPs to all five of the Big Five extinctions.
For decades, the sheer size of LIPs and the wide margin of error in attempts to put dates on rock formations led geologists to suspect that LIPs erupted slowly over millions of years; Any associated damage can easily be ignored. But four years ago, better rock dating techniques have reduced those error margins, revealing two important things: LIPs are bursting hard muscles that’s geologically fast (thousands of years), and they’re always consistent exactly with multiple extinctions.
Seth Burgess, a geochronologist from the US Geological Survey, told me about his observations while dating part of the Karoo-Ferrar LIP in Antarctica:
“Every single rock I want from Ferrar—and we’re talking up the mountain, down in the valley, from one side of the continent to the other along the Transantarctic Mountains—they’re all 182.6 years old. It’s all the same rock. It gave me a great sense of it all in one shot. It’s not a slow-moving event.”
Burgess used the latest dating techniques to show that the Siberian LIP Traps were still the way, and that happened exactly at the same time as the end-Permian mass extinction-Earth’s most severe. “We dated the first magmas to spread outside in the shallow Siberian crust and think these magmas are the culprit,” he said. “This spread happened very quickly and at exactly the same time as the extinction.”
As someone told me years ago, there is a lot of time in deep time. However, LIP and destruction occur exactly at the same time, although the gaps between these eruptions are millions or tens of millions of years. That seems to be enough to declare a LIP smoking gun scenes of destruction.
This is true for most LIP nuclear links. Regular matches confirmed for the mid-Cambrian, late-Triassic, Toarcian, and others. And it’s not just a date match. volcano nickel and mercury have been found in many destructive situations, including for those Ordovician we had Cretaceous incident.
So if the serial killer is the volcanism associated with the LIP eruption, when will it strike again?
To answer that, we need to find out what causes the world to bleed lava on such a scale. And for that, we need to look deep into the Earth’s fabric.
The chimney of the apocalypse
Scientists like Barbara Romanowicz and Scott French of UC Berkeley did just that—looked deep into the mantle. They use vibrations from large earthquakes around the world to illuminate the interior of our planet and take pictures, rather like a medical ultrasound.
Their pictures show fat coat of plumes, regions of hot rock as wide as France, rising like chimneys through the mantle. Today, they burn volcanoes in places like Hawaii and Iceland—tourist destinations instead of global apocalypses. But evidence in the opinion that LIPs are also about coat of plumes. The plumes responsible for LIPs must be very strong.
In their quest to understand what can turn these plumes into killers, scientists and mineralogists are looking for the driving force that produces the plumes. The Earth’s molten core provides that heat drive in motion of mantle materials, like a stove burning a pot of water, so it makes sense to focus on the roots of the plumes in the cross-section border. There, scientists have discovered blister-like patches with properties that indicate molten metal may have been leaking from the inside.
Earthquake waves traveling through those zones are unusually slow, giving them the name: “Lower Transgression Zones” or “ULVZs.” As a result, seismic waves are bent, like light through thick glass. The patches appear to be confined to the roots of the plumes and have been confirmed to reside below Iceland, Hawaii and Samoa so far. Their seismic activity suggests that they may contain molten rock. While the mantle behaves a bit like a fluid, the pressures there ensure that the rock remains firm until shallow depths.
“What’s special about these ULVZs is that they’re also very fat!” Romanowicz told Ars. “They seem to be 800km in diameter at the first border – we can’t say for sure. It is still a mystery what they are. I think that (it) is partially melted, but exactly what their effect is, how long they last, this is something we need to investigate further. “
Catherine McCammon, of the University of Bayreuth in Germany, and Razvan Caracas, a mineralogist from the University of Lyon, are investigating the properties of the ULVZ by looking at how rocks behave under conditions of we think it is at the base of the coat. “There aren’t many people who do this kind of testing,” McCammon explained. “You need a synchrotron, so this makes it an exceptional group of people.”
Them synchronization that he refers to is a particle accelerator three times the size of a football field, which produces X-rays 100 billion times stronger than those of a hospital X-ray machine. X-rays are beamed through mineral samples that are compressed and heated to recreate conditions at the core-mantle boundary. Data from X-rays track the vibrations of atoms of materials, which allows us to measure the speed of seismic waves through those samples. Razvan, in contrast, uses quantum mechanics to calculate the it is theorized Seismic wave velocity of the same material. The difference between theoretical and quantitative results suggest that there is molten material in the ULVZ. “We think it has some degree of melting,” said Catherine. “Either melt a part, or melt the metal from the center.”
Other scientists have found clues drinking water in ULVZs, and underlying melting may explain why some gems have microscopic traces of iron-nickel alloy– the materials that make up the core. If ULVZs are indeed patches where the molten core is leaking into the mantle, perhaps the Earth’s core has a role in turning the plumes into mass killers. But it’s core dancing not supported by hot-spot lava chemistry, and there it is and there is no evidence for any material from the core ever making it to Earth’s surface in a plume, so ULVZs remain an enigma for now.
Maybe the ‘special sauce’ that turns the plumes into a cloud is much closer to the Earth’s surface.