Talk:Timeline of glaciation

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[edit] Additions 2005

I added a graph of Atmospheric CO2 data from ice core samples which closely correspond to global temperature averages.

I tried to sort out the glacial periods and names as best I could, but the older names are known not to represent singular glacial periods, so I tried to represent that on the graph.

I expanded the table to track four sets of names, referenced in the article links. I also corrected the table to match the article dates, but it's still a mess on the older dates.

I welcome anyone else's effort to help clarify this information, even if it is less than well defined. I HOPED the CO2 graph could help shed some light on the glacial periods.

Tom Ruen 15:11, 3 December 2005 (UTC)

[edit] Asian glaciers?

The table is great - but it made me think of another question. Why aren't there Asian names? Was there an ice sheet over Siberia too? I've been looking for a map but with no luck. HMAccount 22:27, 25 June 2006 (UTC)
A good project if you can find more information. Good luck! :) Tom Ruen 21:36, 26 June 2006 (UTC)
Thanks :) I've had a look on the web, but it is taking too much time. I have found the Siberian ice sheet equivalent of the Riss-Wurm interglacial, the Kazantseva interglacial, and the Wurm equivalent is the Zyryanka glacial period. But there was also the Karginski interglacial and the Sartan glacial period which seem to have been more recently, in the late Wurm, which will throw off your table, so am holding off on adding to it. (reference: [1]) So far come up dry on any earlier glacial periods. Frustrated: I bet it's in any standard Russian geology text :) HMAccount 19:52, 27 June 2006 (UTC)
Dates are a big issue to connect up since there's different estimates even if you find names. If you feel confident in names and sources for the most recent periods, its seems worth putting up, at least if you include some stub articles in the linked names as well. Of course just including "research notes" here in talk can be helpful if someone else can find more. Tom Ruen 21:03, 27 June 2006 (UTC)
It is a problem and I notice that some foreign periods are being merged into the the North American system without any discussion or evidence for analogy that I can see. Can anyone link me to policy on this as the scheme is all over the place at the moment? - 217.33.16.99 11:13, 23 February 2007 (UTC)

[edit] The present Pleistocene ice age

The 2nd para refers to "The present Pleistocene ice age". But acc to the Pleistocene article, that era ended 12,000 years ago. If "Pleistocene" is being used in a different sense here, perhaps that should be explained. Nurg 23:18, 3 November 2006 (UTC)

[edit] Brunhes-Matuyama reversal

Someone had added the sentence: "The Brunhes-Matuyama reversal occurred 780,000 years ago, approximately coincident with MIS19, the "Cromerian Complex" interglacial I, and can be used to date sediment cores." While I agree that the Brunhes-Matuyama reversal may be used to date certain sediment cores, and occurred ~780,000 tears ago, I think that the reference to the Cromerian may be off as well as MSI-19. Additionally, I am not sure that it belongs in the article, certainly not as a stray sentence after the Pleistocene tables. If verified, something like it might constitute a note to the table. --Bejnar 16:41, 3 May 2007 (UTC)

I thought it was interesting to have the time connection. How about added as a "see also"? (Even if the reversal article itself needs expanding!) Tom Ruen 20:03, 3 May 2007 (UTC)

[edit] Conflict with Article on Ice Ages

The other article (http://en.wikipedia.org/wiki/Ice_Age [2]not sourced) gives different dates for the earliest hypothesized ice age periods.

The variance could be due to different measurement techniques. Or one set of figures may have been superseded by a more valid set. JP 01:27, 21 September 2007 (UTC)

[edit] Wisconsin vs. Wisconsinan

Back 25 years ago when I was in college, the four main North American glaciation periods were referred to either by state name+term like glacial period/epoch or simply in the possessive form of the state most affected. Usage should be consistant.Krumhorns (talk) 17:15, 23 January 2008 (UTC)

[edit] Structure of the article + Pleistocene glaciation

The article starts with There have been four major periods of glaciation in the Earth's past. and expands a bit on that topic. The next three sections are about the Pleistocene glacial cycles, and finally there is a short section about glaciations in earth's history, of which the Pleistocene glaciation is but one. This section should precede the PG sections, I changed that accordingly.

Addionally there's either too much Pleistocene glaciation or too few about the older glaciations in this article. The Pleistocene glaciation is a link to and treated in great detail in Quaternary glaciation, and some of the information here in Timeline of glaciation seems to be missing there. I propose to move the in-detail stuff to Quaternary glaciation, and give a short outline of all four major glaciation episodes here.--Jo (talk) 19:33, 30 January 2008 (UTC)

Yeah, the QG is pretty much a half-finished article that is missing chunks of information here and there. ~ UBeR (talk) 16:02, 25 February 2008 (UTC)

[edit] Land-based chronology of Pleistocene glacial cycles

All names in the table column Alpine pointed to the North-American terms (second column, not linked). I pointed them to the appropriate article (currently most of them redirects to one of the different terms in each row) and added links to every unlinked term. The definitions of each of these stage are different and ought to have their own articles.Jo (talk) 09:47, 25 February 2008 (UTC)

Yeah, there was a rather fueled discussion about that at last glacial period, I believe. ~ UBeR (talk) 16:03, 25 February 2008 (UTC)
Been there... ;) I'm currently collecting sources: where, when, and who defined what. You have a nice collection on your page, quite inspiring. Jo (talk) 17:14, 25 February 2008 (UTC)
Yeah, I was thinking of adding (inter)stadials, but that's probably more work than I'm interested in. ~ UBeR (talk) 06:35, 26 February 2008 (UTC)