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Re: [dinosaur] Burning fossil field jackets + dinosaur greenhouse climate + Karoo mudstone + oceans after K-Pg impact






Van: dinosaur-l-request@mymaillists.usc.edu <dinosaur-l-request@mymaillists.usc.edu> namens Ben Creisler <bcreisler@gmail.com>
Verzonden: donderdag 10 juni 2021 23:14
Aan: dinosaur-l@usc.edu <dinosaur-l@usc.edu>
Onderwerp: [dinosaur] Burning fossil field jackets + dinosaur greenhouse climate + Karoo mudstone + oceans after K-Pg impact
 
This makes me wonder whether all those nutrients being released through mass destruction of living and dead creatures worldwide, may not have resulted in extremely rich soils worldwide during the first years/decades/centuries of the Paleocene, perhaps mitigating the effects of sunlight being blocked, acid rains and so on to some extent, at least locally and soon creating a bonanza for any surviving terrestrial creatures able to make the least do with such conditions. Is this anywhere close to likely?
Also, how likely is the possibility that some small terrestrial enclaves survived the whole ordeal more or less unscathed and served as loci for subsequent recolonisation for the rest of the world?

Regards,

Brian
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Julia Brugger, Georg Feulner, Matthias Hofmann & Stefan Petri (2021)
A pronounced spike in ocean productivity triggered by the Chicxulub impact.
Geophysical Research Letters (advance online publication)
doi: https://doi.org/10.1029/2020GL092260
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020GL092260


There is increasing evidence linking the mass-extinction event at the Cretaceous-Paleogene boundary to an asteroid impact near Chicxulub, Mexico. Here we use model simulations to explore the combined effect of sulfate aerosols, carbon dioxide and dust from the impact on the oceans and the marine biosphere in the immediate aftermath of the impact. We find a strong temperature decrease, a brief algal bloom caused by nutrients from both the deep ocean and the projectile, and moderate surface ocean acidification. Comparing the modeled longer-term post-impact warming and changes in carbon isotopes with empirical evidence points to a substantial release of carbon from the terrestrial biosphere. Overall, our results shed light on the decades to centuries after the Chicxulub impact which are difficult to resolve with proxy data.

Plain Language Summary

The sudden disappearance of the dinosaurs and many other species during the end-Cretaceous mass extinction 66 million years ago marks one of the most profound events in the history of life on Earth. The impact of a large asteroid near Chicxulub, Mexico, is increasingly recognised as the trigger of this extinction, causing global darkness and a pronounced cooling. However, the links between the impact and the changes in the biosphere are not fully understood. Here, we investigate how life in the ocean reacts to the perturbations in the decades and centuries after the impact. We find a short-lived algal bloom caused by the upwelling of nutrients from the deep ocean and nutrient input from the impactor.


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