Talk:Late Ordovician mass extinction

message: khhg
You aren't combining the End Ordovician and End Silurian extinctions are you?
Dragons flight 23:03, Sep 19, 2004 (UTC)
To address Dragons flight's question, the end Ordovician extinction event began with a major glaciation which resulted in a major sea level drop (as much as 80 meters according to some sources).  This resulted in a major extinction as continental shelves dried up and habitats changed or disappeared.  Later, the glaciers melted, sea levels rose as high or even higher than they were before the glaciation, and the survivors of the first event were hit by another extinction event as environments and habitats changed yet again.  All of this occured during the 1.9 million years of the Hirnantian stage.
My sources for this are The Great Ordovician Biodiversification Event, Edited by Barry Webby and Mary Droser, 2004, Columbia University Press; and A Geologic Time Scale 2004, Edited by Felix Gradstein, James Ogg, and Alan Smith, 2004, Cambridge University Press.
Hope this helps.
--Lenn 03:00, Jun 24, 2005 (UTC)
The webpage on footnote 6 speaks of Gondwana passing under the NORTH pole, which is contradicted by every map I've seen elsewhere, plus the wikipedia article; this source should be tossed out of the article as unreliable.  I haven't read the book sources, but several maps and a few text pieces I've seen suggest that Gondwana was under the south pole tens of millions of years *before* the extinction event, which makes it very unlikely to be the proximate cause.134.29.178.146 (talk) 14:52, 7 February 2012 (UTC)
thread_title: Confusion

message: Hmm messing through the extinction events i have two remarks, the first being why is not immediatly the option of extraterrestial impact(s) , tested? I suppose it is, but i have read older reports telling most major extinction events have a Sr-rich layer right under. It would be relatively easy to establish and a rather telling fact for ppl like me (wogohob eg. first focusses on oceanographic aspects). A period of 1.6 million year for restabilisation of the ecosphere is somewhat high but nothing really exceptional. A severe event, upsets speciation for at least a million years, several severe events, as apparently geologically , paleologically proven in this case, would prolong that from the first occurence of the event to 1 million years after the last occurance. Ice ages have not as far as i know had any severe impact on diversity mondially. Ofcourse they might locally lead to cambrian circumstances, my bet would be eg. under the ice of antartica one could find confusingly cambrian-like geologys.
Also if the effect was due 'natural' fluctuations of the earths circumstances several genera would hardly have been touched. Wich is according to the article not the case. Simple question, can we establish wether meteorite impact was the cause before hopefully shouting earths natural fluctuations may provide sufficient (lack of) CO2 for extinction?
As an example , the broken up comet that hit jupiter, might have taken 2 passages before all parts hit jupiter(would that be 60ky or 600?).77.248.56.242 13:39, 2 July 2007 (UTC)
thread_title: Causes

message: The end of the second event occurred when melting glaciers caused the sea level to rise and stabilize once more.
This information is nice, but what triggered it? It seems obvious that the extinction event ( in essence an ice age) ended when the ice melted, as is suggested above, but if a ceasing of vulcanism and continued weathering of the Appalachian Mountains decreased CO2 and began the extinction through what can be inferred as a general cooling of the Earth due to the removal of this greenhouse gas from the atmosphere, then what caused the glaciers to melt? (The ice age to end?)
If the answer is something as simple as - the Appalachians stopped weathering... I believe it might yet be worth mentioning. More likely, the answer is much more complex and involved than this or what is currently written. Indeed, the article also mentions other contributing factors for the cooling of the earth, yet this sentence, read so soon after the previous section implies that potentially, the end of the weathering of the mountains alone was enough to replenish CO2, reheat the earth, end the ice age, and caused life to flourish once more. And that's only if you stop and think about what was actually written. 
Thanks for taking the time to read and respond, as necessary. Regards.  — Preceding unsigned comment added by 173.56.60.219 (talk) 04:42, 30 November 2011 (UTC)
thread_title:  End of the Event 

message: On 
:<ref>&#lt;/ref>
... as an edit. (just made this date)
Despite the above section's disclaimer, the theory of a sudden ice age triggered by gamma radiation striping part of the ozone layer is out there, as this program repeated, bringing me to check the terms and our coverage... 
* The program, definitely differs as to it boldly states it was the second most serious. Unfortunately, wasn't recording so can't recheck context. 
: I actually believe it's sense was in terms of percentage of biota species lost... but hacked together a smoke and mirrors spin phrase to include both numbers
... so you all could figure out how to adjudicate and write about such disputes. (Hey, I was just watching some tube! <g>) Experts, wake up! <g> // FrankB 21:36, 13 November 2008 (UTC)
thread_title:  "[[Ordovician extinction]]" 

message: Something's wrong with the image, it is placed in the upper left corner withing a screen-wide frame now.. --CopperKettle 18:08, 18 December 2009 (UTC)
thread_title: Image

message: One or more portions of this article duplicated other source(s). The material was copied from: (see below). Infringing material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you.  J. Spencer (talk) 00:53, 21 October 2010 (UTC)
thread_title:  Copyright problem removed 

message: I changed section title to "Impact." While the list of mass extinctions at Extinction_event#Major_extinction_events positions the Ordovician–Silurian fifth in the list, that list is in reverse chronological order, with the most recent at the top of the list. If the list were in chronological order, this would have been first. I thought it best to change the title to one that doesn't reference an ordinal. I chose "Impact" for now.  SlowJog (talk) 02:04, 31 January 2016 (UTC)
thread_title:  Impact / Fifth Mass Extinction 

message: Hello fellow Wikipedians,
I have just modified one external link on Ordovician–Silurian extinction events. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20080509124723/http://hannover.park.org/Canada/Museum/extinction/ordcause.html to http://hannover.park.org/Canada/Museum/extinction/ordcause.html
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
Cheers.—InternetArchiveBot (Report bug) 14:40, 11 December 2017 (UTC)
thread_title:  External links modified 

message: Could you add information on this study to the article? Possibly to the sections "Impact" and "Possible causes". From the study:
This work extends the duration of anoxia to >3 Myrs–notably longer than well-studiedMesozoic ocean anoxic events
...
The correlation between the second pulse of the Late Ordovicianextinction4and the prolonged low-diversity interval3with the onsetand persistence of widespread global marine euxinia indicates amajor potential role for global ocean deoxygenation (and/or itsexternal drivers) in governing global marine biodiversity
...
Prolongedrecovery from the Late Ordovician mass extinction supports thenotion that ocean deoxygenation has repeatedly had prolongedimpacts on marine ecosystems at the timescales of geologicalstages/age
I added this to 2020 in science:
*A new study shows that the duration of anoxia approximately 444 million years ago was longer than 3 million years and affirms that the prolonged lack of oxygen in the oceans contributed to the Ordovician–Silurian mass extinction events at the time.
--Prototyperspective (talk) 17:01, 23 May 2020 (UTC)
thread_title:  "Persistent global marine euxinia in the early Silurian" 

message: It’s claimed that species were “decimated”
That word has a specific meaning, and it’s not appropriate here. But I can’t think of a replacement term that fits here to indicate the species’ went extinct.
Please help! UsersLikeYou (talk) 09:01, 4 February 2022 (UTC)
thread_title:  Under “impact on life”