Misplaced Pages

Talk:Cretaceous–Paleogene extinction event: Difference between revisions

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editContent deleted Content addedVisualWikitext
Revision as of 19:26, 12 July 2007 editOrangemarlin (talk | contribs)30,771 edits What happened?← Previous edit Latest revision as of 16:45, 17 August 2024 edit undoZzzs (talk | contribs)Extended confirmed users6,377 edits Where is the finger actually?: ReplyTags: Mobile edit Mobile web edit Advanced mobile edit Reply 
(899 intermediate revisions by more than 100 users not shown)
Line 1: Line 1:
{{Talk header}}
{{WP1.0|WPCD=yes|class=B|importance=high|VA = yes}}
{{Article history
{{FAOL|Portuguese|pt:Extinção K-T}}
|action1=GAN
{{assessed|Natural disasters|] ]}}
|action1date=2007-07-20, 04:21:56
{{ExtinctionTalk}}
|action1result=listed
{{WikiProject Geology|class=B|importance=high}}
|action1oldid=145754514
{{WikiProject Dinosaurs|class=B|importance=high}}


|action2=WPR
|action2date=2007-08-02, 08:34:27
|action2link=Misplaced Pages:Scientific peer review/Cretaceous–Tertiary extinction event
|action2result=reviewed
|action2oldid=148672280


|action3=FAC
|action3date=07:15, 4 September 2007
|action3link=Misplaced Pages:Featured article candidates/Cretaceous–Tertiary extinction event
|action3result=promoted
|action3oldid=155510182


|action4=FAR
== ] section ==
|action4date=14:22, 11 July 2008
|action4link=Misplaced Pages:Featured article review/Cretaceous–Tertiary extinction event/archive1
|action4result=kept
|action4oldid=223887119


|currentstatus=FA
"Other scientists think the extensive volcanic activity in India known as the Deccan Traps may have been responsible for, or contributed to, the extinction. However, paleontologists remained skeptical, as their reading of the fossil record suggested that the mass extinctions did not take place over a period as short as a few years, but instead occurred gradually over about ten million years, a time frame more consistent with massive volcanism. There was also a certain general distrust of a group of physicists intruding into their domain of expertise."
|maindate=March 13, 2008
|topic=Natsci
|itndate=March 6, 2010
}}
{{WikiProject banner shell|collapsed=yes|class=FA|vital=yes|1=
{{WikiProject Biology|importance=High}}
{{WikiProject Death|importance=High}}
{{WikiProject Dinosaurs|importance=Top}}
{{WikiProject Evolutionary biology|importance=High}}
{{WikiProject Extinction|importance=Top}}
{{WikiProject Geology|importance=High}}
{{WikiProject Palaeontology|importance=High}}
}}
{{User:HBC Archive Indexerbot/OptIn
|target= Talk:Cretaceous–Tertiary extinction event/Archive index
|mask= Talk:Cretaceous–Tertiary extinction event/Archive <#>
|leading_zeros=0 |indexhere=yes |template=
}}
{{User:MiszaBot/config
| algo=old(90d)
| archive=Talk:Cretaceous–Paleogene extinction event/Archive %(counter)d
| counter=4
| maxarchivesize=75K
| archiveheader={{Automatic archive navigator}}
| minthreadsleft=5
| minthreadstoarchive=1
}}


==Notes to update Cretaceous stage==
I don't see quite how this makes sense. Paleontologists are sceptical of the gradual-extinction massive volcanism theory caused by the Deccan Traps because their information points to a gradual extinction? It then goes on to say how they slowly came to accept a rapid extinction theory such as meteor impact instead of the slow-extinction Deccan Traps one. I'm not sure quite what whoever wrote this means to say, so I haven't changed it, but someone should make it clearer. --] 05:20, 19 May 2005 (UTC)
Prior to the 2021, that's results of end Cretaceous when asteroid hits the Mexico did happen to 66 million years ago, but according to 2021's paper by Bland et al., they gave it to update the Cretaceous stage was 146-67 million years ago (Early Cretaceous from 146-101 Ma; Cenomanian from 101-94 Ma; Coniacian from 90-86 Ma; Campanian from 84-75 Ma, Maastrichtian from 75-67 Ma).
:You have to provide a reference, not just change the text so that it no longer reflects the source cited. It would be best to give the source on this talk page so that it can be discussed. It will probably take more than one paper to gain general acceptance of revision of the dating of the International Commission on Stratigraphy. ] (]) 16:02, 13 July 2021 (UTC)
::It would also be great if that sentence would be rewritten, right now it's an unintelligible blob that says nothing. What's the "that's results of end Cretaceous when asteroid hits the Mexico did happen to 66 million years ago, but according to 2021's paper by Bland et al."? What should it mean? ] (]) 15:37, 21 August 2021 (UTC)
:::This paper is by "Chris Bland the Whale King"? The same barely coherent vandal who, until he was finally banned, kept vandalizing pages with blatant errors and nonsensical original research?--] (]) 18:37, 30 August 2021 (UTC)


== Citation 5 ==


Citation 5 is a photography book, and so doesn't really seem relevant to the statements connected to it,
== ''footnote''
'With the exception of some ectothermic species such as sea turtles and crocodilians, no tetrapods weighing more than 25 kilograms (55 pounds) survived'
==
I suspect theres an error here <!-- Template:Unsigned IP --><small class="autosigned">—&nbsp;Preceding ] comment added by ] (]) 11:53, 10 November 2021 (UTC)</small> <!--Autosigned by SineBot-->


== Please add info on decline in dinosaur biodiversity millions of years before & timeline items ==


I think at the least a brief mention is warranted. It's featured in ] like so:
Deleted long uneeded ''footnote'' quote about Shiva crater. The reference is there as a link for those interested. Also deleted slanderous garbage from previous discussion comment above. We can be civil here. -] 18:26, 13 Nov 2004 (UTC)


<blockquote>A study indicates a substantial decline in dinosaur ] millions of years before the ].<ref>{{#invoke:cite news ||last1=Hunt |first1=Katie |title=Fossil egg analysis in China adds to debate of what may have caused dinosaurs' demise |url=https://edition.cnn.com/2022/09/23/world/dinosaur-egg-fossils-extinction-scn/index.html |access-date=19 October 2022 |work=CNN |date=23 September 2022 |language=en}}</ref><ref>{{cite journal |last1=Han |first1=Fei |last2=Wang |first2=Qiang |last3=Wang |first3=Huapei |last4=Zhu |first4=Xufeng |last5=Zhou |first5=Xinying |last6=Wang |first6=Zhixiang |last7=Fang |first7=Kaiyong |last8=Stidham |first8=Thomas A. |last9=Wang |first9=Wei |last10=Wang |first10=Xiaolin |last11=Li |first11=Xiaoqiang |last12=Qin |first12=Huafeng |last13=Fan |first13=Longgang |last14=Wen |first14=Chen |last15=Luo |first15=Jianhong |last16=Pan |first16=Yongxin |last17=Deng |first17=Chenglong |title=Low dinosaur biodiversity in central China 2 million years prior to the end-Cretaceous mass extinction |journal=Proceedings of the National Academy of Sciences |date=27 September 2022 |volume=119 |issue=39 |pages=e2211234119 |doi=10.1073/pnas.2211234119 |pmid=36122246 |pmc=9522366 |bibcode=2022PNAS..11911234H |language=en |issn=0027-8424|pmc-embargo-date=March 19, 2023 }}</ref></blockquote>


There may also be more info in the latest section of ] not yet included in the article. Please check that too.
Someone may want to place a link page for KT boundry to this site.
----
I removed a list of explanations. This appears to have been shamelessly ripped off from . --]
----


{{reflist-talk}} ] (]) 21:13, 28 November 2022 (UTC)
Can anyone tell me exactly (ok, roughly will do!) how long the dino-extinction took please? Deni.
----


:This issue is discussed in the article, which states that there have been some studies showing a decline in diversity in the late Cretaceous and others no decline. This is one more regional study and does not seem significant enough to warrant mentioning. ] (]) 23:01, 28 November 2022 (UTC)
"K-T" is on most of the redirects to ], and that seems logical since it is abbreviating something hyphenated. (It's the head of what i used in my attempt to find the article.)


== Massively glitched page--huge amount of content potentially lost ==
Yet "KT" is used twice in the first 'graph. Is that bcz the pros use KT, or is it just a guess that no one has fixed? --] 22:26, 2004 Feb 20 (UTC)


I just finished a large edit in visual editing mode and added dozens of new papers like and . After I submitted my edit, I looked at the Citations section and the papers I added were nowhere to be found. After several hours of work. '''What the **** happened?!''' How did this glitch happen??? I remember copying and pasting every link to single reference I added into the citation tool!!! Is there any way to recover my work so I do not have to do it all over again???!!! ] (]) 01:18, 19 November 2023 (UTC)
Actually, i now see that "K-T" is used in the 4th- and 3rd-to-last 'graphs, which sound more knowledgable. I'll change the KT references soon if no one responds, since the article is self-contradictory. --] 22:32, 2004 Feb 20 (UTC)
:I do not know about visual editing mode but my method in standard mode is to click preview first to check and paste and copy the revised article into Word if there looks like there might be a problem. This usually works to provide a backup, but not always. ] (]) 08:54, 19 November 2023 (UTC)
----


== Where is the finger actually? ==
Didn't the orignal Alvarez paper concern specifically Gubbio, Italy? IIRC, the evidence became "worldwide" at a later date. --]] 05:42, 2004 Apr 29 (UTC)


The picture with the finger is captioned "finger is below the actual Cretaceous–Paleogene boundary", but the same picture in ] is captioned "Finger is on the actual K–Pg boundary". They can't both be correct. ] (]) 03:05, 15 August 2024 (UTC)
--------
Use of the Alvarez K-T extinction model as de facto is not warranted. The same mechanism would need to be invoked to explain other mass extinctions such as the Permian (whose process profiles do not so easily accord with an impact diagnosis). Presumably, those disappearing species which heralded the extinction process several million years prior to the K-T boundary must have used sophisticated astrometric instrumentation to see the asteroid coming, frightening themselves out of existence. Occam&rsquo;s razor should dictate the more likely probability of gradual but heavy volcanism and subsequent environmental change. Evidence for this prosaic alternative is much easier to come by than a largely transatlantic led indulgence for a Hollywoodised disaster scenario. Work on other external impositions on the terrestrial environment, by MacClean and others, also deserve more merit - despite the lack of the PR machine afforded the Alvarez clan.


:They both have the same caption that they're on the the actual boundary. ]] ]]. Are you confused between these two images: ] and ]? For the record, they're not the same pictures. <span style="font-family:Times New Roman;font-size:100%;color:#00008B;background-color:transparent;;CSS">]]</span> 03:11, 15 August 2024 (UTC)
It is also no accident that an asteroidal impact theory prospers in a nation keen on indulging strategic defence on an industrial scale.
::No. the picture on this article has the full caption
::"Complex Cretaceous–Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near Geulhem, The Netherlands (finger is below the actual Cretaceous–Paleogene boundary);"
::The one on the other article has the caption
::"Complex Cretaceous-Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near Geulhem, the Netherlands. Finger is on the actual K–Pg boundary."
::They are the same picture and are described the same except for finger position. The one with people in it is irrelevant. ] (]) 07:49, 15 August 2024 (UTC)
:::I have now found time to go back and check the history of both pages. The image appears to have been added in 2013 to both this page and ], with the caption stating the finger is ''on'' the actual boundary. In 2017, someone changed the caption here to ''below''. I'm assuming the correct description, then, is that the finger is on the boundary rather than below it, and I will change the wording on this article accordingly. ] (]) 13:33, 17 August 2024 (UTC)


:Figure 5 in (in Dutch) from the same locality says that the K/Pg boundary is at the change from light yellow to dark yellow rock, in which case the finger is just below the boundary (by a few mm). ] (]) 16:35, 17 August 2024 (UTC)
Steve Ringwood
::I went ahead and corrected the location based on the publication. <span style="font-family:Times New Roman;font-size:100%;color:#00008B;background-color:transparent;;CSS">]]</span> 16:45, 17 August 2024 (UTC)

-------

Well said, indeed, Steve. The problem is that whereas you have sound reasoning on your side, you are opposed by tons of lurid magazine covers showing asteroids hitting the earth with dinosaurs in the foreground plus a dozen films with the same premise. The real science got lost in this a long time ago - which forgive me seemed to happen on a regular basis in any undertaking where Gould was involved.

If people wonder why this issue was so important to clarify instead of obfuscating, it is that our planet seems to be undergoing similar climate changes right now directly related to magnetic fields and volcanism, especially on the deepest part of the ocean floor. The Alvarez-Gould circus of Lysenkian proportions may very well have left mankind stunned like mullets when they should have been preparing themselves for the possible onset of a second Ice Age.

I'm sure Steven J. Gould would be happy that his legacy will consist not only of derailing anthropology for the past thirty years but also being instrumental in the deaths of millions of people in the Northern hemisphere who were watching the skies for theatrical cosmic intruders when they should have been keeping their eyes right down here on the planet around them instead, where the real action was.

(effeminate crypto communist edited these comments to make them more thought neutral) 13 Nov 2004

'''- Cleve Blakemore
'''
-------
Whence the K?

:''Geologists' abbreviating of the Cretaceous period by "K" reflects the need to avoid ambiguity: the more obvious "C" would also be the natural first choice for the "Carboniferous" period.''

That makes no sense: K is just as ambiguous as C. Actually, the K stands for ], the German term for Cretaceous. Geology was happening in Germany when the term was coined back in the 19th century.
<br>&mdash;] 12:50, 12 Nov 2004 (UTC)

:Others attribute the K to the Greek "Kreta" which was a natural alternative to the Latin "Creta". Both of which mean chalk and latin/greek were still all the rage at the time. Incidentally, the name Cretaceous was first proposed by Jean-Baptiste-Julien d'Omalius d'Halloy in 1822 in relation to sections in France.

:] 15:17, Nov 12, 2004 (UTC)




== Search Problem ==


Listening to Melvin Bragg's programme on Radio 4 (http://www.bbc.co.uk/radio4/history/inourtime/) today (23 June 2005), I wanted to read more on the discussion topic, 'KT Boundary'. On typing in 'KT Boundary' in the search box, I got nothing in the first four or five pages that would have taken me there, even though there's a 'Category:KT boundary'. Being still fairly new to Misplaced Pages, I don't know how to set up synonyms for the proper article.
--] 08:42, 2005 Jun 23 (UTC)
:Not sure why that wouldn't return the correct article, because ] and ] both redirect to this page, and normally the search takes you directly to the relevant article if the title matches the search query.
:If you want to make redirects, it's quite simple - if you want article A to redirect the reader to article B, then just type #REDIRECT <nowiki>]</nowiki> in article A - you can see what I mean . ] 09:07, 23 Jun 2005 (UTC)

== Supernova hypothesis section ==
Er, this section says, "The radiation from a supernova explosion should ''contain'' the plutonium isotope Pu-244," emphasis mine. This is kind of confusing. Are we saying that Pu-244 would be thrown off by the explosion and hit the planet, or are we saying the radiation would create Pu-244? Or is there some use of the word "radiation" that I'm confused about? -] 13:31, 26 July 2005 (UTC)

:Pu-244 would be present in material ejected from a supernova; it is distinct from the supernova's radiation which would not include Pu; nor do I think such radiation would normally create it even at relatively near proximity to a supernova. The sentence was probably meant to read "The '''fallout''' from a supernova explosion should contain the plutonium isotope Pu-244," and I've changed the article to reflect that. --] | ] 22:46, 30 November 2005 (UTC)

==Image==
Perhaps a pointer could be added to the image of the KT boundary to assist the reader's non-geologist eye to what feature exactly we should be looking at here? --] 18:41, 14 August 2005 (UTC)
:It would also be nice to know the geographic location of the photo. ] 23:05, 14 August 2005 (UTC)

::Sorry, taken in badlands near Drumheller, and will add that; however, I can not recall which black mark is the KT Boundary, and don't have enough skill to identify. Need someone of greater skill to put arrow line to identify.] (UTC)

(also written in the pertinent image discussion page) I'm a closet geologist, but I strongly think that the KT boundary does not appear in drumheller. This picture does appear to be possibly from drumheller or dinosaur provincial park, however both areas contain older sediments (where dinosaur bones would be common). Eastend saskatchewan, 400 or so km southeast, has a perfect roadside view of the boundary. Much of that area was spared glaciation and the more superficial KT boundary remains. I suggest a picture of this be uploaded in place of the current picture. (Which is a beautiful badlands shot but does not show the KT boundary). If this picture does include the KT boundary, it isn't from drumheller and the caption should say so

== Layout ==

Should we change the layout to more accurately organize the page? I suggest the page be layed out like this:

1 Casualties of the extinction<br>
2 Theories<br>
2.1 Impact event and iridium <br>
2.2 Chicxulub crater <br>
2.3 Deccan traps <br>
2.4 Multiple impact event<br>
2.5 Supernova hypothesis <br>
3 Further skepticism <br>
4 Other mass extinctions <br>
5 References and external links<br>

] 18:47, 2 January 2006 (UTC)

:I have gone ahead and modified the headers to how I was suggesting. I saw the KT event article on the Portuguese wikipedia site and noticed that page was done how I was thinking, so I went ahead and made the necessary changes. ] 00:31, 5 January 2006 (UTC)

== Small flaw in the KT event being caused by an impact ==

I would guess that an impact crater, such as the one in the Yucatan, would send tsunamis onto any adjoining or possibly distant landmasses. Wouldn't that landmass exhibit some unusual fossil formations, meaning aquatic animals (from large to small) showing up in what would be generally considered dry areas? I never know how good the fossil record is, so maybe we cannot know this, or maybe it just hasn't been discovered yet. I've got to say, if some credible source could show aquatic fossils inland by sever kilometers, that would be some strong proof of an impact event rather than some terrestrial event such as the Deccan Traps. ] 00:01, 2 May 2006 (UTC)

:We do have tsunami deposits in North America. ] 04:05, 9 July 2006 (UTC)

I saw on a special on the Discover Channel where one of the scientist from the original team that found the Yucatan crater had made an interesting discovery about 100KM from the edge of that crater in Mexico. Between the KT boundary and the iridium layer was something like 10 feet of sandstone. In that sandstone were fossil remains of aquatic worms and crabs that were only found in the ocean. The theory was that the sand could have only come from the ocean and got there from the tsunami caused by the impact. once the water receeded, all that sand was left and then the "asteroid fallout" fell on top of that. I could be wrong on the details for I didn't exactly write it down while watching it, but that's pretty much how it was explained. Hope this helps. ] 00:58, 12 September 2006 (UTC)

== Global Firestorms? ==

"A global firestorm may have resulted as incendiary fragments from the blast fell back to Earth. Analyses of fluid inclusions in ancient amber suggest that the oxygen content of the atmosphere was very high (30-35%) during the late Cretaceous . This high O2 level would have supported intense combustion. The level of atmospheric O2 plummeted in the early Tertiary period."

I softened this from "A global firestorm" to "Global firestorms." Is this just speculation or is there some credible theory? If so I'd like to see some reference to it. I'm a layperson but I'm skeptical to the idea that the earth, due to high oxygen content, was like a powderkeg just waiting for a match to initiate a conflagration. There are plenty of natural firestarters: lightning storms in particular, plus lesser asteroid strikes, or spontaneous combustion of rotting material (which would be much more common back then, given 35% O2). These would cause natural fires and prevent things from reaching the point where flammable material was abundant enough to support a global firestorm. The high O2 level would simply lower the threshold between what's flammable and what's not. Lightning fires would burn off all the flammables, just as they do today if not prevented.

"Plummeted" is a relative term...it probably didn't happen overnight. The asteroid impact theory implies widespread reduction in living plants (food for the dinosaurs) due to the global dust cloud. Any such reduction must have been drastic to bring about extinctions, otherwise a few pockets of dinosaurs would survive and reproduce. This massive die-off in plant life would account for the oxygen level decrease, since plants are the primary source of atmospheric O2.

As I said I'm no expert. I have no idea whether Alvarez' theory is correct; but I'm not buying the global-firestorm idea. without a credible source.
If there's no referencable discussion of this from a reputable source I think the paragraph should be removed. ] 03:40, 9 July 2006 (UTC)

:It is a real theory, from some time in the late 80s. Aside from the fact that the impact definitely would have started fires and soot is found in a great many K/T boundary sections, I'm not aware of anyone who presently takes the rest of that (i.e. the oxygen bits) seriously. ] 04:10, 9 July 2006 (UTC)

:OK good enough. ] 17:54, 9 July 2006 (UTC)

Saw it on one of the many Discover Channels I get with DirecTV. Sorry, but don't remember name or channel, but it was late August 06. Had Gerta (was that her name?), the scientist (also a professor at some Ivy league school) who originally challanged the whole asteroid theory and then the guy who actually came up the with theory and found the crater in Yucatan. These two just hammered at each other, it was quite comical. Anyway, being that these two were on the show, I can say it must be credible. There was also another femal professor on the show (British accent - sorry dont know her name) who dug in the KT boundary all over the world looking for charcoal. The theory was that if there was a large global firestorm, there would be charcoal all over the KT boundary throughout the world. They found some soot, but no charcoal. So in their opinion, their could not have been a mass burning for what happened to all the organic material if it didn't turn to charcoal? Maybe I am simplifying it, but this was the theory presented. ] 00:51, 12 September 2006 (UTC)

the documentary is "What really killed the dinosaurs" a UKTV Documentary production. It is quite a dry, but well paced documentary, much better than other American productions that I have viewed. It does however feature prominant geologists discussing a large meteor impact whilst casually mentioning that there was a lot of volcanism around this time! Well Duh! A massive release of energy into a tectonic plate would surely cause a chain reaction where any energy stored up in surrounding fault lines or nearby volcanic systems would be released .



------

Though most likely, the Cretaceous-Tertiary extinction event wasn't necessarily caused by an asteroid. This article mentions scepticisms, but has few alternatives. On the website http://www.dinosaur.org/extinction.htm, they have a pie chart (http://www.dinosaur.org/extinction970404.jpg) showing possible reasons for the extinction event. I'd put that in this article, but I don't know where it would go, or what kind of copywrite it would have. Any ideas?

Birds are listed as being both significantly effected and minimally effected. Clarification?
] 15:54, 5 December 2006 (UTC)
:The article says that Enantiornithes and Hesperornithiformes became extinct but the groups which were ancestral to modern birds seem to have survived reasonably well. Enantiornithes and Hesperornithiformes were not the ancestors of any modern birds. <small>—The preceding ] comment was added by ] (] • ]) 23:51, 22 December 2006 (UTC).</small><!-- HagermanBot Auto-Unsigned -->


==1.5 years on and still just as uninformative==
Still the article (after my original complaint in Aug '05 above) gives no indication anywhere in the text, anywhere in the captions or anywhere in the talk or description pages of the images themselves as to just what in the heck the reader is looking at when he/she views these supposed images of the KT boundary at the top of the page. I argue now, that without indication of the KT boundary either in caption or within the image as an arrow or something, '''anything''', that they are useless to the reader and merit removal from the article. The current images are equivalent to uploading this image to the article on New York State without any further supplementary information and simply captioned it "New York". Its simply unacceptable. --] 08:38, 25 December 2006 (UTC)
:I agree. The pics are useless to non-geologists, while geologists would need much more detailed pics.] 13:14, 9 January 2007 (UTC)
::I made a modified image (added a line marking the boundary, based on the info and photos , but I can't seem to get it to display - can someone who is smarter with images than I am help? Many thanks - ] 16:20, 9 January 2007 (UTC)
:::I see the changes you made to my pic; they are showing up here. Thanks for doing that! ] 18:30, 9 January 2007 (UTC)
::::Great, must be my cache or something. Thanks for the original photo - I hope I credited the original correctly and adequately in the modified one, if not please fix it in whatever way you would want it to be - I definitely don't claim anything for just putting that line on it!! cheers ] 18:49, 9 January 2007 (UTC)
:::::Yeah, you can try clearing your cache. I updated the new ] so that the old image doesn't have to show full size, reducing server load. ] 19:37, 9 January 2007 (UTC)
:::The extra line in the Trinidad Lake pic doesn't help - it looks artificial and there's no explanation. I suggest: (a) drop the Trinidad Lake pic as it's just too small; (b) use the left half of the Drumheller pic and replace the right side with a set of labels pointing to the "normal" latest Cretaceous sediments, the boundary clay, the iridium and / or charcoal layer at the boundary, and the earliest Tertiary sediments. I expect (b) can only be done by a geologist - any volunteers?] 19:47, 9 January 2007 (UTC)
::::I added an explanation for the line on the caption. On the full-size image, it is easy to see the thin white bed that marks the break - that was how I figured out where it must be, by comparing to the pics in the USGS site referenced above (and also why I didn't draw the line all the way across, so that one could see the rocks there). I don't know anything about the Drumheller area, can't help there... Anyway, if y'all decide the pics are still uninformative, do what you will. (Maybe lift some of the images from that USGS site? I think they are all black & white, but maybe useful) Cheers, ] 20:08, 9 January 2007 (UTC)
::::2560x1920 should be plenty big (that's how big the Trinidad Lake pic is, if you click on it to show full-res). ] 20:58, 9 January 2007 (UTC)

== K-T Boundary ==

Hej! On the picture KT_boundary_054, is the K-T boundary the "gray" area between the "black" and the "green"? ] 19:11, 18 January 2007 (UTC)
:Per the discussion above, we don't know - that's why some suggested that this image should be deleted. We need either the original photographer, or someone familiar with the boundary in the area where the photo was taken, to help. ] 19:41, 18 January 2007 (UTC)
::Oopps! I should have read it. Thanks anyway! ] 19:46, 18 January 2007 (UTC)
I am the original photographer of the Trinidad picture. The white line was marked by ] based on , especially on . ] 20:59, 18 January 2007 (UTC)
:Hi Nationalparks, I thought he was referring to the other pic, from Alberta, which still needs some indication of the K-T position. Is that one yours too? Cheers ] 21:15, 18 January 2007 (UTC)
::Sorry, that one isn't mine... ] 22:33, 18 January 2007 (UTC)

== A sentence ==

According to the article, one of the extinction patterns is that: "Organisms which depended on photosynthesis became extinct or suffered heavy losses. And so did organisms whose food chain depended on photosynthesising organisms."

Am I missing something? Just how many types of organisms do ''not'' ultimately depend on photosynthesising organisms? Apart from chemoautotrophic bacteria, that is :). --] 17:22, 9 February 2007 (UTC)

:Maybe "Organisms which directly depended on..." woluld help a bit. This excludes the detritus-based species, as their food was photosynthesised many years, decades (or even more) befor the event. --] 13:53, 21 March 2007 (UTC)

== Small Predatory Dinosaurs Missing ==

Has it ever been suggested that large dinosaurs, both carnivorous and herbivorous, became cannibalistic due to a lack of vegetation? Would it explain the lack of fossils and presence of teeth if they became the last food source of large dying reptiles?
] 06:42, 17 February 2007 (UTC)

:Not to my knowledge. And animals cannot simply switch diet arbitraily. Most need a very specific diet and cannot digest anything else. Humans (and pigs) are the exception rather than the norm in this. --] 16:19, 15 April 2007 (UTC)

== Misleading asteroid impact illustration ==

The 'Artistic depiction of asteroidal impact' shows an asteroid that is much too big, compared to the estimated size given in the article. In the illustration, the asteroid is about 200 km in diameter, roughly 20 times too wide. An impact of such a large asteroid would cause a lot more damage than the one that caused the K-T extinction event: assuming the impact still occured at the same speed, the energy released would be 8000 times as much (20x20x20), probably causing an extinction of all life on earth (even destroying the entire bacterial population, since the crust of the whole planet would be nearly liquified). I understand it's only an illustration, so maybe I'm just being picky? ] 17:28, 21 March 2007 (UTC)

==Alvarez Hypothesis=Impact Event?==
Is the section titled 'Alvarez Hypothesis' a summary of ]? ] 06:12, 22 March 2007 (UTC)

== Too many lists? ==

This article is full of bulleted lists, many of which should probably be converted into paragraphs. It is a bit excessive. --] (] - ]) 16:49, 29 May 2007 (UTC)
:Almost all the bulleted text has now been converted to prose; I've left the last set of bullets, as it enumerates the list of extinction theories. The rest of the bulleted lists are gone, and in fact, there was no need for them in the first place, as often even two items were presented as lists. I think the next step should be to combine short sections (such as the section on how land life was affected and the section on how marine life was affected). <font color="#0000FF">]</font> 14:27, 17 June 2007 (UTC)

::I've been searching a few articles, and I was thinking that those sections could be boosted with more information rather than combining them. It's Father's Day out here in the US of A, so I'm going to hang out, get treated like a KIng for a couple of hours (until everyone starts whining), then I'll try to add in my edits this evening. The article is about 200% better than it was two days ago! ] 14:38, 17 June 2007 (UTC)
:::OK, then we'll expand the sections. Sounds good. Happy Father's Day, OM! :) <font color="#0000FF">]</font> 16:31, 17 June 2007 (UTC)
::::Why are we including ''two'' URLs, like in the first red diff, ? <font color="#0000FF">]</font> 06:59, 18 June 2007 (UTC)
:::::Because I had a margarita in one hand, editing with the other? Actually, I missed the first link, because I was trying to figure out the doi number. But the link you reverted (and for punishment you have to go edit Living dinosaurs for a day) was actually to the whole article, while the link you kept was for the abstract. I'll let you revert, with a long explanation on how I rule. ] 12:43, 18 June 2007 (UTC)
::::::I have switched to your URL, as I guess it's the full paper. And I included a note about how you rule. But I'm not spending a day editing Living dinosaurs until you do the full WP:DINO member initiation, editing the lovely dinosaur articles about bits of wood mistaken for dinosaurs. <font color="#0000FF">]</font> 13:09, 18 June 2007 (UTC)

==Dinosaur diversity==
The sentence "There was no obvious reduction in dinosaur diversity, not even in the latest part of the Maastrichtian (Fastovsky and Sheehan 1995 and later papers)." sends some alarm bells off in my head. Although this may have been the finding of Fastovsky and Sheehan, I don't think this is a majority view (or at least there is considerable debate about this still in the paleontological community). <font color="#0000FF">]</font> 06:59, 3 July 2007 (UTC)
:Reads like another undue weight issue (this article has many). If the prevailing wisdom is that the sky is blue, and there is one paper saying it is green, I'm not sure it's even worthy of an encyclopedia article to even mention green. In fact, and I don't pretend to play a paleontologist, it is not the view that I know. Fastovsky and Sheehan's works need to be researched a bit more to see if it's been debunked, especially in the ensuing 12 years. ] 14:52, 3 July 2007 (UTC)
::For what it's worth I think the Fastovsky and Sheehan paper is correctly linked in the references, and is 2005 rather than 1995 As far as I can tell in that paper they mostly just express a difference of opinion - based on the poor data -- that the diversity decline seen is simply normal variation. They don't seem to me to be particularly adamant about it. Cheers ] 16:12, 3 July 2007 (UTC)

== Stumbled in ==
Hi, while I'm a fairly new editor and just stumbled over here from checking out the project page, I had Prof Alvarez as an undergrad shortly after wide disemmination of the theory based on irridium. The article seems pretty good actually, I had expected (based on other wikiexpiereince) there to be pages of awful arguement about nothing substantive. my only comments really would be to go over the whole thing slowly and make sure that all the refs. say what you indicate, and to link the summary of theories, comination of theories section to some refs. Keep up the good work! --] 03:59, 8 July 2007 (UTC)

==What happened?==

The article disappeared from my watch list. Did I do something to offend the dying dinosaurs? ] 09:35, 12 July 2007 (UTC)
:I moved the page, from ] to ], because ] states that En-dashes are used "To convey the sense of “to” or “through”, particularly in ranges (“pp. 211–19”, “64–75%”, “the 1939–45 war”, “May–November”) and where movement is involved (“Dublin–Belfast route”)." The move caused the page to not be on your watchlist anymore. It also caused many pages to be redirected to the new page. I've just now fixed all the double redirects, but I did not fix the regular redirects. <font color="#0000FF">]</font> 09:47, 12 July 2007 (UTC)
::I just saw that. How do you find which pages redirect to an article? I can't believe you just went through and added all of those last night!!!! Or morning (depending on where you are located--actually I don't know where you are located). ] 18:16, 12 July 2007 (UTC)
:::The toolbox on the left-hand side has a link called "what links here". It gives a list of articles that link to the article you're working on. If you notice that a ''redirect'' page has redirects going to it, those will be double redirects: a redirect that points to another redirect (bad). The software only redirects once and the software will not follow the second redirect, in order to prevent infinite loops, so the poor reader ends up at a redirect instead of an article. Whenever an admin moves a page, s/he should check for double redirects, and fix them accordingly. Of course, anyone can change a redirect. I am in Arizona, for the record. :) <font color="#0000FF">]</font> 18:28, 12 July 2007 (UTC)
::::On second thought, looking at your edit summary (''Whew. I thought I did something wrong, or you permanently banned me from the article!!!!''), maybe an apology is in order, OM. I do apologize: I didn't realize that moving the article to this slightly different title would cause so much confusion. You didn't do anything wrong, of course, and even if you had, I have no power to ban you from the article (]). Bans (and blocks) also don't affect watchlists. I had to laugh at the thought that you put so much work into this article, and then worried you were suddenly "banned" from it, though. <font color="#0000FF">]</font> 19:09, 12 July 2007 (UTC)

:::::If I really thought I was banned, I certainly would have left you a nastygram!!!! I was kidding. This project (meaning Misplaced Pages) has got to be the most complicated set of things that I've ever seen. I couldn't figure out why it disappeared from my watchlist, so I did a small edit just to see if it showed up. I didn't know about the what links here link. I'm going to check it out! ] 19:26, 12 July 2007 (UTC)

Latest revision as of 16:45, 17 August 2024

This is the talk page for discussing improvements to the Cretaceous–Paleogene extinction event article.
This is not a forum for general discussion of the article's subject.
Article policies
Find sources: Google (books · news · scholar · free images · WP refs· FENS · JSTOR · TWL
Archives: Index, 1, 2, 3, 4Auto-archiving period: 3 months 
Featured articleCretaceous–Paleogene extinction event is a featured article; it (or a previous version of it) has been identified as one of the best articles produced by the Misplaced Pages community. Even so, if you can update or improve it, please do so.
Main Page trophyThis article appeared on Misplaced Pages's Main Page as Today's featured article on March 13, 2008.
In the news Article milestones
DateProcessResult
July 20, 2007Good article nomineeListed
August 2, 2007WikiProject peer reviewReviewed
September 4, 2007Featured article candidatePromoted
July 11, 2008Featured article reviewKept
In the news A news item involving this article was featured on Misplaced Pages's Main Page in the "In the news" column on March 6, 2010.
Current status: Featured article
This  level-4 vital article is rated FA-class on Misplaced Pages's content assessment scale.
It is of interest to multiple WikiProjects.
WikiProject iconBiology High‑importance
WikiProject iconCretaceous–Paleogene extinction event is part of the WikiProject Biology, an effort to build a comprehensive and detailed guide to biology on Misplaced Pages. Leave messages on the WikiProject talk page.BiologyWikipedia:WikiProject BiologyTemplate:WikiProject BiologyBiology
HighThis article has been rated as High-importance on the project's importance scale.
WikiProject iconDeath High‑importance
WikiProject iconThis article is within the scope of WikiProject Death, a collaborative effort to improve the coverage of Death on Misplaced Pages. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.DeathWikipedia:WikiProject DeathTemplate:WikiProject DeathDeath
HighThis article has been rated as High-importance on the project's importance scale.
WikiProject iconDinosaurs Top‑importance
WikiProject iconThis article is within the scope of WikiProject Dinosaurs, a collaborative effort to improve the coverage of dinosaurs and dinosaur-related topics on Misplaced Pages. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.DinosaursWikipedia:WikiProject DinosaursTemplate:WikiProject Dinosaursdinosaurs
TopThis article has been rated as Top-importance on the project's importance scale.
WikiProject iconEvolutionary biology High‑importance
WikiProject iconThis article is part of WikiProject Evolutionary biology, an attempt at building a useful set of articles on evolutionary biology and its associated subfields such as population genetics, quantitative genetics, molecular evolution, phylogenetics, and evolutionary developmental biology. It is distinct from the WikiProject Tree of Life in that it attempts to cover patterns, process and theory rather than systematics and taxonomy. If you would like to participate, there are some suggestions on this page (see also Misplaced Pages:Contributing FAQ for more information) or visit WikiProject Evolutionary biologyEvolutionary biologyWikipedia:WikiProject Evolutionary biologyTemplate:WikiProject Evolutionary biologyEvolutionary biology
HighThis article has been rated as High-importance on the project's importance scale.
WikiProject iconExtinction Top‑importance
WikiProject iconThis article is a part of WikiProject Extinction, an attempt at creating a standardized, informative, comprehensive and easy-to-use resource on extinction and extinct organisms. If you would like to participate, you can choose to edit this article, or visit the project page for more information.ExtinctionWikipedia:WikiProject ExtinctionTemplate:WikiProject ExtinctionExtinction
TopThis article has been rated as Top-importance on the importance scale.
WikiProject iconGeology High‑importance
WikiProject iconThis article is within the scope of WikiProject Geology, an attempt at creating a standardized, informative, comprehensive and easy-to-use geology resource. If you would like to participate, you can choose to edit this article, or visit the project page for more information.GeologyWikipedia:WikiProject GeologyTemplate:WikiProject GeologyGeology
HighThis article has been rated as High-importance on the project's importance scale.
WikiProject iconPalaeontology High‑importance
WikiProject iconThis article is within the scope of WikiProject Palaeontology, a collaborative effort to improve the coverage of palaeontology-related topics and create a standardized, informative, comprehensive and easy-to-use resource on Misplaced Pages. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.PalaeontologyWikipedia:WikiProject PalaeontologyTemplate:WikiProject PalaeontologyPalaeontology
HighThis article has been rated as High-importance on the project's importance scale.

Notes to update Cretaceous stage

Prior to the 2021, that's results of end Cretaceous when asteroid hits the Mexico did happen to 66 million years ago, but according to 2021's paper by Bland et al., they gave it to update the Cretaceous stage was 146-67 million years ago (Early Cretaceous from 146-101 Ma; Cenomanian from 101-94 Ma; Coniacian from 90-86 Ma; Campanian from 84-75 Ma, Maastrichtian from 75-67 Ma).

You have to provide a reference, not just change the text so that it no longer reflects the source cited. It would be best to give the source on this talk page so that it can be discussed. It will probably take more than one paper to gain general acceptance of revision of the dating of the International Commission on Stratigraphy. Dudley Miles (talk) 16:02, 13 July 2021 (UTC)
It would also be great if that sentence would be rewritten, right now it's an unintelligible blob that says nothing. What's the "that's results of end Cretaceous when asteroid hits the Mexico did happen to 66 million years ago, but according to 2021's paper by Bland et al."? What should it mean? Artem.G (talk) 15:37, 21 August 2021 (UTC)
This paper is by "Chris Bland the Whale King"? The same barely coherent vandal who, until he was finally banned, kept vandalizing pages with blatant errors and nonsensical original research?--Mr Fink (talk) 18:37, 30 August 2021 (UTC)

Citation 5

Citation 5 is a photography book, and so doesn't really seem relevant to the statements connected to it, 'With the exception of some ectothermic species such as sea turtles and crocodilians, no tetrapods weighing more than 25 kilograms (55 pounds) survived' I suspect theres an error here — Preceding unsigned comment added by 80.4.214.138 (talk) 11:53, 10 November 2021 (UTC)

Please add info on decline in dinosaur biodiversity millions of years before & timeline items

I think at the least a brief mention is warranted. It's featured in 2022 in science like so:

A study indicates a substantial decline in dinosaur biodiversity millions of years before the Cretaceous-Paleogene extinction event.

There may also be more info in the latest section of Timeline of Cretaceous–Paleogene extinction event research not yet included in the article. Please check that too.

References

  1. Hunt, Katie (23 September 2022). "Fossil egg analysis in China adds to debate of what may have caused dinosaurs' demise". CNN. Retrieved 19 October 2022.
  2. Han, Fei; Wang, Qiang; Wang, Huapei; Zhu, Xufeng; Zhou, Xinying; Wang, Zhixiang; Fang, Kaiyong; Stidham, Thomas A.; Wang, Wei; Wang, Xiaolin; Li, Xiaoqiang; Qin, Huafeng; Fan, Longgang; Wen, Chen; Luo, Jianhong; Pan, Yongxin; Deng, Chenglong (27 September 2022). "Low dinosaur biodiversity in central China 2 million years prior to the end-Cretaceous mass extinction". Proceedings of the National Academy of Sciences. 119 (39): e2211234119. Bibcode:2022PNAS..11911234H. doi:10.1073/pnas.2211234119. ISSN 0027-8424. PMC 9522366. PMID 36122246.{{cite journal}}: CS1 maint: PMC embargo expired (link)

Prototyperspective (talk) 21:13, 28 November 2022 (UTC)

This issue is discussed in the article, which states that there have been some studies showing a decline in diversity in the late Cretaceous and others no decline. This is one more regional study and does not seem significant enough to warrant mentioning. Dudley Miles (talk) 23:01, 28 November 2022 (UTC)

Massively glitched page--huge amount of content potentially lost

I just finished a large edit in visual editing mode and added dozens of new papers like "Deccan volcanism caused coupled pCO2 and terrestrial temperature rises, and pre-impact extinctions in northern China" and "No post-Cretaceous ecosystem depression in European forests? Rich insect-feeding damage on diverse middle Palaeocene plants, Menat, France". After I submitted my edit, I looked at the Citations section and the papers I added were nowhere to be found. After several hours of work. What the **** happened?! How did this glitch happen??? I remember copying and pasting every link to single reference I added into the citation tool!!! Is there any way to recover my work so I do not have to do it all over again???!!! Anteosaurus magnificus (talk) 01:18, 19 November 2023 (UTC)

I do not know about visual editing mode but my method in standard mode is to click preview first to check and paste and copy the revised article into Word if there looks like there might be a problem. This usually works to provide a backup, but not always. Dudley Miles (talk) 08:54, 19 November 2023 (UTC)

Where is the finger actually?

The picture with the finger is captioned "finger is below the actual Cretaceous–Paleogene boundary", but the same picture in Cretaceous–Paleogene boundary is captioned "Finger is on the actual K–Pg boundary". They can't both be correct. PointlessUsername (talk) 03:05, 15 August 2024 (UTC)

They both have the same caption that they're on the the actual boundary. . Are you confused between these two images: File:LWA with Walt.JPG and File:Cretaceous Paleogene clay at Geulhemmergroeve.jpg? For the record, they're not the same pictures. ZZ'S 03:11, 15 August 2024 (UTC)
No. the picture on this article has the full caption
"Complex Cretaceous–Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near Geulhem, The Netherlands (finger is below the actual Cretaceous–Paleogene boundary);"
The one on the other article has the caption
"Complex Cretaceous-Paleogene clay layer (gray) in the Geulhemmergroeve tunnels near Geulhem, the Netherlands. Finger is on the actual K–Pg boundary."
They are the same picture and are described the same except for finger position. The one with people in it is irrelevant. PointlessUsername (talk) 07:49, 15 August 2024 (UTC)
I have now found time to go back and check the history of both pages. The image appears to have been added in 2013 to both this page and Cretaceous–Paleogene boundary, with the caption stating the finger is on the actual boundary. In 2017, someone changed the caption here to below. I'm assuming the correct description, then, is that the finger is on the boundary rather than below it, and I will change the wording on this article accordingly. PointlessUsername (talk) 13:33, 17 August 2024 (UTC)
Figure 5 in this publication (in Dutch) from the same locality says that the K/Pg boundary is at the change from light yellow to dark yellow rock, in which case the finger is just below the boundary (by a few mm). Mikenorton (talk) 16:35, 17 August 2024 (UTC)
I went ahead and corrected the location based on the publication. ZZ'S 16:45, 17 August 2024 (UTC)
Categories: