[Rockhounds] Volcanism as a prime cause of mass extinctions

[Dora Smith]

I looked into this in great detail.

It seems that the impact happened during the Deccan eruptions. The bulk 
of hte eruptions had already happened.   The massive earthquakes caused 
by the impact changed the nature of the Deccan flows but did not make 
them more violent.  The evidence as to the state life on earth was in 
when the eruption occurred seems scanty and equivocal.

However, I think we should be less concerned about what DID cause the 
mass extinction, than about what COULD cause a mass extinction if it 
happened again, and exactly why that is.  Reasonably, our worry is for 
the future, not 65 million years in the past.  We pretty well know what 
happens when various sorts of volcanoes strike.

It did amaze me that the Toba volcano was larger than Yellowstone's 
largest eruption and humanity was living at the time, removing 
speculation on that, though, remarkably, I'm just not seeing clear 
evidence on what impact it had on Antarctica OR southern Africa.

I also don't know after all that looking into it how the Deccan traps 
eruption compared to the Siberian traps eruption that we know caused a 
major extinction.

But, I AM convinced that if a meteor that size were to strike similar 
geology again, a mass extinction would occur.  However, the evidence on 
how long the effects would last is hazy!   It makes a big difference for 
a world that should plan for major disasters whether we're talking about 
three years before we can plant crops and go on with our lives, or 
seven, or three hundred. What sorts of shelters would we need, what 
storage of food and livestock?  And the question about magnetic 
destruction of everything electronic and how to protect it - there seems 
to be little solid about it.  And it's crucial to the survival of 
civilization, and everything our civilization has achieved.  Or should 
we just bury an entire paper library under a mountain like the Mormons 
have done?

Yours,

Dora Smith

On 3/28/20 2:21 PM, Paul wrote:
> Racki, G., 2020, Volcanism as a prime cause of mass extinctions:
>
> Retrospectives and perspectives, in Adatte, T., Bond, D.P.G., and
>
> Keller, G., eds., Mass Extinctions, Volcanism, and Impacts: New
>
> Developments: Geological Society of America Special Paper 544, p. 1–34
>
> https://www.researchgate.net/publication/337951571_Volcanism_as_a_prime_cause_of_mass_extinctions_Retrospectives_and_perspectives 
>
>
> https://www.researchgate.net/profile/Grzegorz_Racki
>
> Racki, G., Rakociński, M., Marynowski, L. and Wignall, P.B., 2018.
>
> Mercury enrichments and the Frasnian-Famennian biotic crisis:
>
> A volcanic trigger proved?. Geology, 46(6), pp.543-546.
>
> https://www.researchgate.net/publication/326031821_Mercury_enrichments_and_the_Frasnian-Famennian_biotic_crisis_A_volcanic_trigger_proved 
>
>
> Let's be careful out there,
>
> Paul H.
>
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