Mercury from 252 million years ago was discovered in rocks and contributes to the growing belief that the & # 39; Great Dying & # 39; was caused by volcanoes.
Researchers found strong mercury signals in rocks that date back to this time when 95 percent of all life had been swept away.
The signals were found at 10 different locations around the world and were dated by studying the teeth of petrified eel-like creatures.
Causes of the so-called & # 39; Great Dying & # 39; have been heavily discussed, but this study provides convincing evidence that volcanic eruptions were to blame.
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Instead of coming out of openings in stereotypical conical volcanoes, the eruptions from the Siberian traps mostly came from huge gorges in the earth's crust (stock photo)
Popularly known as & # 39; the Great Dying & # 39 ;, the massive extinction that occurred 252 million years ago killed a catastrophic 95 percent of life on Earth.
The event is marked in the geological record as the boundary between the Permian and Triassic periods.
Instead of coming out of openings in stereotypical conical volcanoes, the eruptions came from huge gorges in the earth's crust.
& # 39; Typically, when you have large explosive volcanic eruptions, a lot of mercury is released into the atmosphere & # 39 ;, explains author and geologist Thomas Algeo of the University of Cincinnati.
In addition, the eruptions are thought to cause huge coal deposits to ignite, releasing mercury vapor high into the atmosphere.
Ultimately, this mercury settled on the earth again and left an ecological signature in marine sediments around the world.
It is this signature that the researchers have discovered in 10 sites around the world.
The research locations were chosen to represent different marine environments, including shallow and deep settings, both near and far from the burst location.
In particular, the catastrophe has destroyed the living amphibians and reptile species of that time, and it is thought that they have created the environment that would eventually allow new groups – including the dinosaurs – to evolve.
Both land and marine species were affected by the catastrophe.
It has long been argued that mass extinction was activated due to massive volcanic activity in the so-called Siberian traps.
The pitfalls are in what has become central Russia today.
In total, the Siberian traps would have pumped up to 0.7 million cubic miles (3 million cubic kilometers) of ash into the atmosphere during volcanic activity.
In comparison: the violent eruption of Mount St Helens in Washington, USA, in 1980 sent only 0.2 cubic kilometers (1 cubic kilometer) of ash to the atmosphere.
This is even though ash from the mountain was recorded as far away as Oklahoma, 2,000 miles (3,218 kilometers) away.
& # 39; Mercury is a relatively new indicator for researchers. It has become a hot topic for investigating volcanic influences on major events in the history of the Earth, & # 39; said Professor Algeo.
The researchers used the sharp, petrified teeth of creatures called conodonts (pictured, stock image) to date the rocks in which they deposited mercury
Professor Algeo collaborated with colleagues from both Cincinnati and the China University of Geosciences,
The researchers used the sharp, petrified teeth of creatures called conodonts – which look like eels – to date the rocks in which they have deposited mercury.
Like the majority of creatures that lived on the planet 252 million years ago, conodonts were hit hard by the Permian Trias extinction event.
However, they survived 52 million years.
Like the majority of creatures that lived on the planet 252 million years ago, conodonts were hit hard by the Permian Trias extinction event. However, they survived 52 million years. (Pictured: an artist & # 39; s impression of a conodont, Promissum pulchrum, that lived around 232 million years before the Great Death)
According to Professor Algeo, the amount of material released by the traps – in particular greenhouse gases – is said to have warmed the planet by an average of 10 ° C.
This climate change would have been an important factor in the massive extinction.
& # 39; We often keep scratching about what exactly is the most harmful, & # 39 ;, Professor Algeo explained.
& # 39; Creatures that were adapted to colder environments were not lucky. So my guess is that temperature change is the number 1 killer, & he added.
In addition, acid rain would have destroyed water bodies, in addition to increasing the acidity of global oceans.
The warmer water could not have contained as much dissolved oxygen, creating dead zones that were inhospitable to life.
The enormous duration of the volcanic eruptions from the falls would have made it even more difficult for life to cope with environmental changes.
& # 39; It is not necessarily the intensity but the duration that matters. The longer this went on, the more pressure was put on the environment, & said Professor Algeo.
Researchers are now trying to determine the extent of the eruptions of the Siberian traps, alongside which of the resulting environmental effects were the most devastating.
The knowledge gained here can be of vital importance in the present time.
& # 39; Human carbon emissions are similar to the situation in the Late Permian, where excess carbon was released by the Siberian outbursts & # 39 ;, said author Jun Shen, researcher at China University of Geosciences, in Wuhan.
This is, according to Professor Algeo, cause for concern.
& # 39; A majority of biologists think we are on the point of a new mass extinction – the sixth major & # 39 ;, he added.
& # 39; What we need to learn is that this will be a serious matter that harms human interests, so we must work to minimize the damage. & # 39;
People who live in marginal environments, such as arid deserts, will suffer first. This will lead to more climate refugees around the world.
& # 39; We are likely to see more famine and mass migration in the worst affected areas & # 39 ;, Professor Algeo adds.
& # 39; It is a global problem and we must recognize and address it proactively; it is much easier to tackle these problems before they reach a crisis. & # 39;
Perm Trias extinction is not the only catastrophe that researchers have studied with basic signatures.
The massive extinction that killed the dinosaurs 65 million years ago is associated with a worldwide signature of concentrated iridium – an element rare on Earth.
Scientists believe the iridium came from a huge meteor that fired the planet from the Gulf of Mexico.
Iridium dust is said to have been blown over the earth and form a thin layer that can be stored in rocks today.
The full findings of the study were published in the journal Nature Communications.
WHAT WAS THE PERMIAN MASS OUTTINCTION?
248 million years ago, the Permian period ended and the Triassic period began.
The mass extinction in the Perm is the nickname & # 39; The Great Dying & # 39; because almost all life on earth has been eradicated.
No less than 96 percent of all life on earth was destroyed.
All life on earth today is descended from those existing four percent species & # 39 ;.
The cause of the massive extinction remains unclear to scientists, although it is thought that it took somewhere between 20,000 and millions of years.
Different events that cause the total collapse of different ecosystems.
It is thought that it was a period of high volcanic activity that may have contributed to extinction.
The eruptions may have affected the ozone layer – which protects the planet from harmful UV radiation.
This high-energy form of radiation can cause considerable damage to living things.