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'Great Dying'; Can't get more world event than this !
Topic Started: May 14 2004, 05:05 AM (194 Views)
somerled
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Admiral MacDonald RN
Hunt for Oil Leads to Crater Linked to 'Great Dying' C250Myr BC , the surface of the earth was nearly sterilised.

Quote:
 
Permian-Triassic extinction, about 251 million years ago. Many scientists suspect a comet or asteroid impact, although direct evidence has not been found. Others believe the cause was flood volcanism from the Siberian Traps and related loss of oxygen in the seas. Still others believe the impact triggered the volcanism and also may have done so during the Cretaceous-Tertiary extinction. The Permian-Triassic catastrophe was Earth’s worst mass extinction, killing 95 percent of all species, 53 percent of marine families, 84 percent of marine genera and an estimated 70 percent of land species such as plants, insects and vertebrate animals.

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Has the smoking gun been found ? WA 'meteor' crater hints at mass extinction
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Sgt. Jaggs
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How about a Voyager Movie
But they believe they have found the smoking gun that shows a meteor sparked the "Great Dying," much as an asteroid wiped out the dinosaurs 65 million years ago forming what is now the Chicxulub crater off Mexico's Yucatan Peninsula.

^^^^So the Yucatan Meteor still gets credit for the Dino kill.
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somerled
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Admiral MacDonald RN
I believe the extinction event that did in the dinosaurs wasn't nearly as dramatic is this event 190My earlier.

Life on earth was very nearly totally done in by this one - that's why it's referred to as the "Great Dying".
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Admiralbill_gomec
UberAdmiral
I'm surprised a certain poster in here didn't blame "Bush Jnr" for this... :lol:
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captain_proton_au
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A Robot in Disguise

Didnt the Permian extinction have something to do with the first sea creatures that evolved to land animals, or it was straight after or because of it? - I remember reading somewhere.
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somerled
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Admiral MacDonald RN
Proton:
I believe amphibians and early dinosaurs were already colonising the land 250My BC.
Anyone up to speed on this ?

Bill:
Now that's a thought. :loling:
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captain_proton_au
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A Robot in Disguise

Amphibians started off about 100 million years before.


Here's an Interesting summary on the timelines


Hmm, cockroaches have been around for about 300 million years, longer than Dinosaurs and a lot of reptiles, little devils!
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somerled
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Admiral MacDonald RN
Proton:
Thought it was something like that - been a long time since I did any geology subjects so I was a bit vague on the time line.
From your source
Quote:
 
Permian Period
290-248 million years ago A single supercontinent, Pangaea, forms as Earth's landmasses collide and merge. Pangaea extends across all climatic zones and nearly from one pole to the other. This supercontinent is surrounded by an immense world ocean.
Extensive glaciation persists in what is now India, Australia, and Antarctica. Hot, dry conditions prevail elsewhere on Pangaea, and deserts become widespread. Invertebrate marine life is rich and diverse at the beginning of the period. Toward the end of this period, mass extinctions occur among large groups of corals, bryozoans, and other invertebrates. The last of the trilobites becomes extinct.
On land, insects evolve into their modern forms; dragonflies and beetles appear.
Amphibians decline in number, but reptiles undergo a spectacular evolutionary development of carnivorous and herbivorous, terrestrial and aquatic forms.
Ferns and conifers persist in the cooler air.


Mesozoic Era (Middle Life). The age of Reptiles.
Three periods: Triassic, Jurassic, and Cretaceous.
Time Geologic Development Life Forms
Triassic Period
248-206 million years ago Pangaea covers nearly a quarter of the Earth's surface. The Triassic Period, unlike the previous periods, is marked by few significant geologic events. Towards the end of the Triassic Period, continental rifting begins to break apart the supercontinent.
The general climate is warm, becoming semiarid to arid. Early dinosaurs evolve. Many are bipedal, fast, and relatively small. The largest Triassic dinosaurs are only 20-feet (6 meters) in length—small when compared to later Mesozoic forms.
Marine reptiles evolve, such as ichthyosaurs and plesiosaurs.
Ferns, cycads, ginkgoes, and conifers flourish.
Mass extinctions occur at the end of the Triassic Period, reducing some marine and terrestrial groups, such as the ammonites, therapsids, early reptiles, and primitive amphibians, by as much as 75 percent. 
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