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6
votes
2answers
47 views

Why are pole reversals not more detrimental to life?

This question is linked to the following question, and has two parts. Mars interdicts approximately 40% of the radiation (per square meter) of the sun that Earth does. It has been claimed that Mars ...
-1
votes
2answers
81 views

What if we detonated the entire worlds nuclear supply in the center of the earth? [closed]

What would the effects of detonating every single nuclear bomb currently in existence at once in the center of the earth? Would the earth simply explode into bits? Would the heat have some sort of ...
11
votes
2answers
3k views

Is it possible that the geomagnetic field reversal led to the extinction of Dinosaurs?

Is it possible that the geomagnetic field reversal with a weakened geomagnetic field over centuries if not thousands of years (according to the Pittsburgh simulation: https://www.psc.edu/science/...
1
vote
1answer
113 views

Permian-Triassic mass extinction. Consequences on Earth's system

Coming from this post: Causes of fluctuations in atmospheric oxygen in past 300 Mya I believe there are a lot of questions still unanswered about Permian-Triassic mass extinction, but I ask only ...
-2
votes
1answer
129 views

Safest spots when an asteroid hits? [closed]

I am breaking this question and no longer making an effort in refining it with the exception of adding an associated link with the scenarios. I always wondered if a devastating asteroid was ...
2
votes
0answers
53 views

How does extinction caused by human activity compare to extinction caused by glaciation?

When or if the current interglacial ends, what sort of extinction level can we expect, and what sort of organisms and ecosystems are affected ? How does this compare with the current extinction rate, ...
1
vote
1answer
94 views

gamma ray burst, extinction-level event

From this subsection in Wikipedia's aricle on extinction event: A nearby gamma-ray burst (less than 6000 light years away) would be powerful enough to destroy the Earth's ozone layer, leaving ...
7
votes
1answer
940 views

How is geological time divided into units?

Earth's history is divided into eons, which are divided into eras, which are divided into periods etc. Consecutive time units differ in their geology and/or fossil species. But what events are the ...
3
votes
0answers
80 views

Connections between marine and terrestrial ecosystems [closed]

First I would like to note that I have only very basic understanding of ecology, biology and paleontology so I can easily miss something very simple. I can envision certain ways marine and ...
3
votes
1answer
68 views

Percentage of Oxgen left after burning all the available biomass

A documentry stated that during the Permian asteroid strike the atmosphere heated up to above 400C, potentially to 600C. As this would ignite most of the biomass, including us, I wondered if this fire ...
2
votes
2answers
157 views

Recovery From the Great Dying

252 million years ago, Earth underwent its worst, most violent chapter in the form of the Permian-Triassic extinction event, or "The Great Dying". 70% of the terrestrial species and 95% of the marine ...
5
votes
1answer
558 views

How long does earth take to recover from mass extinctions? What is “normal”?

Wikipedia states the following about the P-Tr extinction event: "Because so much biodiversity was lost, the recovery of life on Earth took significantly longer than after any other extinction event,[5]...
5
votes
1answer
117 views

Why haven't weeds overtaken the entire planet?

Given how rapidly weed plants spread and grow, choking out all other plant life, how come after millions of years we haven't ended with forests full of thistle or pokeweed, as opposed to pines or oak ...
1
vote
1answer
259 views

What is the natural replenishment rate of oil? [duplicate]

What is the natural replenishment rate of oil? Are extinction events connected with higher production?
9
votes
1answer
245 views

Why is the concept of “mass extinction” a relatively recent development in geology?

The concept of "mass extinctions", with its catastrophic connotations, is a relatively recent development in the geological sciences. It evolved in the early 1980s, driven by two landmark publications ...
10
votes
2answers
270 views

Did a gamma ray burst contribute to the Ordovician mass extinction?

According to the University of California Museum of Palaontology webpage The Ordovician Period, the late Ordovician period witnessed when Gondwana finally settled on the South Pole during the Upper ...
10
votes
1answer
108 views

Are there any metal anomalies other than iridium in the K-Pg boundary?

The iridium anomaly marks the elevated concentration of iridium in sedimentary deposits of the Cretaceous-Paleogene boundary. The iridium is said to come from the impactor, which is supposed to have ...
10
votes
1answer
385 views

Is the Younger Dryas associated with an extinction event?

It's often said that, while warming and cooling have happened before, what is unusual about the current anthropogenic warming is that it's happening so fast, relative to previous warming phases$^1$. ...
7
votes
2answers
744 views

Life on Earth previous to us

I've seen in several places that there seems to be an extinction cycle on Earth of approximately 27 million years. I've read this here: http://www.dailymail.co.uk/sciencetech/article-1294372/Life-...
8
votes
1answer
186 views

What evidence is there that plant evolutionary history “dances to a different beat” than that of animals?

Floral transformations have been due to gradual replacement and piecemeal, not mass extinction. Plant “geoevents”; have not been synchronous with epochal animal originations/ extinctions and hence ...