Consequences of the Permian impacts - Part 1

4. Events and consequences of the Permian impacts

4.1 Geological, meteorological, and paleontological effects of the Permian impacts

a) The thermal energy released by the impact can only be measured in multiples of Teratons of TNT. The mortality radius of Wegener's impact alone was able of eliminating life in most of an entire hemisphere. The thermal irradiation persisted for more than 30 hours.[1]

That is, just the energy of Wegener's impact alone was enough to cause a global extinction.

The thermal pulse resulted in an instantaneous global atmospheric mega-warming that would later be intensified in the long run by other greenhouse gases released.

b) The air blast shockwave caused by Wegener's impact alone[2] caused a momentary overpressure of 300 atmospheres in a large radius around the impact area. The poor inostrancevias[3] were vaporized from the South-American continent and their ashes landed on the other side of the Earth.

c) The pouring lava and the gases released in the area of Wegener Crater caused a mega-warm up and acidification of the oceans for a long period, resulting in anoxia and death of 95% of marine life.

d) The hyper-mega-earthquake[4] of magnitude greater than 13.6 – more than 1.5 million times more intense than the most destructive ever recorded – struck the planet liquefying and uplifting the soils, uprooting trees and throwing both animals and trees several tens of meters above the ground.[5]

Larger animals had their bones broken with the fall and/or were impaled by what was left of the broken trees.

e) The animals and plants that survived the irradiation heat and shock wave from the air blast were slaughtered by the ejecta thrown by the impact.

A significant part of that ejecta returned to Earth after reaching the space and came back as incandescent meteorites – the poor inostrancevias who got to survive until now were roast-smashed throughout the Pangeia.

f) Forest fires have swept the planet, destroying entire ecosystems.

Only the burrowing and small aquatic and terrestrial animals of the least affected environments survived, able to obtain refuge more easily, and relying on minimal amounts of food.

g) The megatsunamis generated by the impact and the ensuing mega-earthquakes annihilated an unquantifiable portion of life on the planet on the first day.

The receding waters washed away much of the fertile land – but in return, always look on the bright side of life,[6] – many forest fires were quickly put out.

h) The volume of dust and ash released into the atmosphere[7] was larger than 5 x 10⁸ km³.

Plants had a hard time surviving with the prolonged absence of sunlight – the global darkness persisted for many and many years.

i) A large part of the planet was buried with layers of tens and even hundreds of meters of stones and dust, making it impossible to renew the vegetation in short time.

The least worst, if we may call it that, was that the volcanic winter was offset by the heat accumulated in the oceans, continental lava spills, and greenhouse effect of the volcanic gases.

j) Rising ocean temperatures have released huge amounts of methane hydrates trapped on the bottom of the seas – and methane is the most potent of greenhouse gases.

k) The warming of the oceans has possibly caused mega-hurricanes occurring for thousands, if not millions of years.

This is a hypothesis that needs to be verified, because hurricanes arise from the difference of temperature between the warm waters and the cold air of the atmosphere.

The warming of the waters was remarkable, but in compensation it is estimated that global averages of atmospheric temperature increased by 15 to 20 degrees Celsius, so what was the gradient at the time? Was it enough to trigger megastorms?

l) The spill of lava in Siberia, the result of Wegener's antipodal impact, possibly intensified by the impacts of Arghanaty A and B, and Tarim, lasted for millions of years.

This enriched the atmosphere with unimaginable amounts of monoxide and carbon dioxide, as well as sulfur dioxide.

The carbon derivatives contributed significantly to the global warming, but sulfur dioxide had a controversial role — it can act both as a heating agent by absorbing solar radiation, as it can be a cooling agent reflecting heat out of the atmosphere.

There is a theory that animals developed biological mechanisms of resistance to sulfur dioxide because they were forced to live so long in absolutely abnormal atmospheric conditions.[8]

We may wonder whether this evolution occurred as a result of Permian trauma or caused by other events before the invasion of dry land by vertebrates.

m) Thousands of volcanoes around the planet erupted simultaneously – needless to mention again how this contributed to the process of extinction.

As a bonus, this triggered new forest fires, destruction of ecosystems and extinctions located nearby, probably on places that were not affected directly by the blast or by the Siberian magma.

n) At least two severe impact events at the end of the Permian – three considering the Bedout Crater – triggered fractures and the break-up of continental blocs, as well as other possible geological events.

We do not know at this time whether other Bedout or Tarim-sized events eventually happened simultaneously or in a short period of time on places where we cannot find those evidences – if there are already subducted craters, we will only discover them if we get to identify their remaining hotspots.

o) All of these combined effects caused 70% of continental life to be extinguished – and by then, there were no more inostrancevias to tell the story.

By comparison, 186 million years later dinosaurs faced better days during the Cretaceous extinction.

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[1] Earth Impact Effects Program

[2] Earth Impact Effects Program

[3] Predatory pre-mammals with an ecological role similar to that of lions and tigers, larger than bears and endowed with long skulls (60 centimeters), all extinct in the Permian crisis.

[4] Patent required.

[5] Earth Impact Effects Program

[6] Monty Python’s Life of Brian, Monty Python, 1979

[7] Earth Impact Effects Program

[8] Mass extinction: Mike Coffin at TEDxHobart video

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