Meteorite causing volcanic eruptions

[Bort]

I’m wondering if a large enough meteorite fell to earth to penetrate the crust, would there be additional material ejected into the atmosphere as there’s now an area for magma to be released?

I’m wondering mainly about the compounding effects of both the material ejected from the ground around the meteorite impact as well as additional ejecta resulting from the weakened crust.

[studiot]

32 minutes ago, Bort said:

I’m wondering if a large enough meteorite fell to earth to penetrate the crust, would there be additional material ejected into the atmosphere as there’s now an area for magma to be released?

I’m wondering mainly about the compounding effects of both the material ejected from the ground around the meteorite impact as well as additional ejecta resulting from the weakened crust.

The question is rather vague, don't you think?

The crust has a widely varying thickness and proximity to magama sources so it partly depends upon where the impact occurs and partly on wht you mean by 'penetrate'.

So can you tighten up the detail of the scenario please?

[joigus]

I suppose that would largely depend on where the meteorite landed, as well as its size (approach rapidities are round 10 km/s I think.) The granite continental crust is very hard, and floats on the basalt, acting like a cushion of sorts. If it landed on basaltic soil, it would probably be more likely to eject lavas to the atmosphere. Also, I think it would depend on the pressure tensions due to seismic activity building up around the landing area. Lines of seismic tension have a fractal dimension, but at a large scale they can be looked upon as..., well, just lines, thereby proportional to R (the Earth's radius.) While the total area that the Earth offers to collision-bound meteorites goes like R². So I surmise it would be unlikely but possible.

I'm not sure by any means of what I said above. There could be more factors involved.

2 minutes ago, studiot said:

The question is rather vague, don't you think?

The crust has a widely varying thickness and proximity to magama sources so it partly depends upon where the impact occurs and partly on wht you mean by 'penetrate'.

So can you tighten up the detail of the scenario please?

Edit: Almost xposted with @studiot. Yes, my answer goes in the direction of trying to guess the unknowns in what he's pointing out.

[MigL]

If I might 'steer' the OP in a slightly different direction...

During the last great extinction, 65 Million years ago, the theory is that, there was much increased volcanic activity already poisoning the environment, and the meteor that hit Chicxulub, in the Yucatan peninsula, only hastened the ongoing extinction of dominant Dinosaurs.

Could it have happened the other way around ?
The meteor hits the Yucatan, and causes not only the devastation of tsunamis, fires, windstorms and global winters for years to come, but also increased volcanic activity for thousands of years to come. And that was the 'nail in the coffin' for Dinosaurs.

IOW, do we have geological evidence of the volcanic activity/meteor timeline ?

[joigus]

21 hours ago, MigL said:

If I might 'steer' the OP in a slightly different direction...

During the last great extinction, 65 Million years ago, the theory is that, there was much increased volcanic activity already poisoning the environment, and the meteor that hit Chicxulub, in the Yucatan peninsula, only hastened the ongoing extinction of dominant Dinosaurs.

Could it have happened the other way around ?
The meteor hits the Yucatan, and causes not only the devastation of tsunamis, fires, windstorms and global winters for years to come, but also increased volcanic activity for thousands of years to come. And that was the 'nail in the coffin' for Dinosaurs.

IOW, do we have geological evidence of the volcanic activity/meteor timeline ?

Good point. +1

It is believed that the impact was so considerable that it actually sent ripples of seismic activity around the world. If the world was going through an especially traumatic seismic/volcanic episode or series of episodes, it would have been the last straw.

Some renowned paleontologists --although not many, I believe-- can't still bring themselves to believe the impact was the main trigger of the catastrophe. I cannot claim I've made any calculations, but a meteorite the size of Mount Everest hitting the ground at 10 Km/s in an oblique trajectory near a seismically active area on a shallow sea, sounds to me like could be enough to do it. The main suspect as to the seismic activity was the formation of the Deccan traps (very far from the impact) and also the mid-Atlantic ridge, pushing America and Eurasia/Africa apart.

I'm waiting for someone with expertise to tell us about what they think could have been the culprit. Plus a summary of the chain of events.

Edited June 8, 2020 by joigus
mistyped

[studiot]

1 hour ago, joigus said:

I'm waiting for someone with expertise to tell us about what they think could have been the culprit. Plus a summary of the chain of events.

For your specific mass extinction event you should read Micheal Benton's (professor of geology Bristol University) book

https://www.amazon.co.uk/When-Life-Nearly-Died-Extinction/dp/0500291934

This details all 5 of the great mass extinctions of the past.

 

But for the OP subject this is the book you want

https://www.google.co.uk/search?ei=a5reXsPpE8qJ1fAP1MSXuAM&q=clive+oppenheimer+eruptions+that+shook+the+world&oq=oppenheimer+eruptions&gs_lcp=CgZwc3ktYWIQARgAMgYIABAWEB46BAgAEEc6BQgAEJECOgUIABCDAToFCAAQsQM6AggAOgQIABBDOgcIABCxAxBDOg0IABCxAxCRAhBGEPkBOgcIABCDARBDOgQIABAKOgQIABANOgYIABANEB5QzgxYwD9gxFBoAHABeAGAAeAEiAGKG5IBCzguNy40LjEuMC4xmAEAoAEBqgEHZ3dzLXdpeg&sclient=psy-ab

 

Oppenheimer is reader in vulcanology University of Cambridge.

He tabulates all the largest known eruptive events.

[joigus]

18 minutes ago, studiot said:

For your specific mass extinction event you should read Micheal Benton's (professor of geology Bristol University) book

[...]

But for the OP subject this is the book you want

[...]

Thanks a lot. How can I ever respond in kind? Would you rather have a rep point or a recommended read?  I don't think I can recommend you a read that will surprise you...

@MigL tells me I hand out rep points like they're candy. I hope it's not me going at it again, @studiot. +1

I'm very loose with rep points. It's better than being loose with guns, I suppose.  

[Area54]

On 6/7/2020 at 10:36 PM, MigL said:

IOW, do we have geological evidence of the volcanic activity/meteor timeline ?

The data as of around 2015 was ambiguous. There are suprisingly few precise dates on the Deccan lavas. (The impact event is much more tightly dated, via the irdium rich layer.)  It remains an interesting problem. I'll have a look for something more recent.

[studiot]

16 minutes ago, Area54 said:

The data as of around 2015 was ambiguous. There are suprisingly few precise dates on the Deccan lavas. (The impact event is much more tightly dated, via the irdium rich layer.)  It remains an interesting problem. I'll have a look for something more recent.

The impact event was effectively instantaneous (though the effects lasted much longer), but the Large Igneous Provinces arise over a million or more years of intermittent outpouring.

You should read at least chapter 6 (p140 - 165) of the Oppenheimer book I recommended.

Here are a few pertinent pages including some data on the size and penetration depth of the Chixulub impactor.

[Area54]

14 minutes ago, studiot said:

The impact event was effectively instantaneous (though the effects lasted much longer), but the Large Igneous Provinces arise over a million or more years of intermittent outpouring.

You should read at least chapter 6 (p140 - 165) of the Oppenheimer book I recommended.

Here are a few pertinent pages including some data on the size and penetration depth of the Chixulub impactor.

Thank you. I am familiar with much of the data on the impact and on LIPs. As you are aware, while the impact was practically instantaneous there are error bars on the dating of that event. Coupl that with the spread of the Deccan  eruption ages and one arrives at uncertainty. My point was - and remains - if a larger number of age determinations, taken with greater precision across the full spread of activity are available, then we can more likely determine with confidence the relative ages of impact - eruptions - extinctions*. Such was not the case the last time I had occassion to look at the research literature. It may be the case now.

*Equally, the last time I looked, there was still debate as to the extent to which some extinctions of some genera preceded the impact and were related to the LIP vulcanicity. Tighter control on the LIP ages can help address this.