Talk:Pleistocene

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[edit] Dates

The arithmetic for the length of the Pliocene in previous paragraph doesn't seem quite right. I think a 2000 year correction to the end of the period has morphed into a 200,000 year shift in the beginning, but maybe I'm missing something. ... And Radiocarbon dating in only good for about 100,000 years? Won't cover the whole Pleistocene, right? So 11,000 is a radiocarbon date, but 1.6 or 1.8 million isn't? Right? But I try not to rewrite things that might be correct. Is a clarification or correction needed?

The current versions of the dates are mine: but this was my "best guess" after examining several web sites, which were unclear and/or disagreed with each other. What you write about limits on radiocarbon dating had puzzled me at the time, I'd guessed some other kind radiometric dating was indended for the earlier dates, but then the 10% or so radiocarbon calibration is irrelevant. However I've seen the 1.6 million vs 1.8 million elsewhere. Please clarify and correct if you know any better, ideally with an authoritive reference if such a thing exists -- Hagedis
The start date depends on the dating of marine clays at the Global Stratotype Section and Point at Vrica in Italy. As best I can determine, the ambiguity in the date there is in fact about 200,000 years. Try a search on GSSP and Vrica. Maybe you can make more sense out of the papers on the subject than I could. They seem to me to be somewhat long on jargon and a bit short on content. DJK
If you're happy with 1.8-1.6 for the start of the Pleistocene, just delete this

I might have missed something, but the first para says the Pleistocene started 1,808,000 yrs ago, and the first section Pleistocene#Dating states 1,806,000. Isn't 1,806,000 correct?--PhilMacD (talk) 14:44, 7 April 2008 (UTC)

The date labeled for the end of the Pleistocene is simply ridiculous. We do not have accuracy to the ten-year mark. I am reminded of an anecdote concerning significant digits where a fourth-grader, being asked how old the earth is, responds: "four billion and three years," having been told the earth was four billion years old as a first-grader. It is misleading to give the impression that we have that kind of accuracy by attaching 50 years to the measurement. --Iamdalto (talk) 16:22, 4 May 2008 (UTC)

[edit] Great Basin anomaly

It is ironic that the American Southwest, now an arid-to-semiarid region, was much moister, with giant lakes, even though almost all of the rest of the unglaciated world was then much drier. Could this have been the result of the topography of the region, with the deep, large valleys becoming their own hydrological systems?

Here's what I figure happened: the high peaks got snow during the winter and it of course melted during the summer, but the meltwater filled the lower levels of the basins as lakes. Cooler temperatures reduced the evaporation, but such little water that evaporated from the lakes tended to remain within the valley, being deposited on the upper walls of the valleys as rain or snow. The basins thus became closed water systems.

In any event, it is worth noting that many of the conceptions of the climatic conditions of the Pleistocene era, that climatic belts simply shifted equatorward as ice sheets advanced and advanced poleward with the retreat of the ice sheets, as might be suggested by the record in the Great Basin, were wrong. The Great Basin is a geologist's paradise because it is accessible, has generally good weather, and has little human influence in the form of farming or other settlement, so it is an easy area for geological exploration -- but it is apparently uncharacteristic of the rest of the world. --66.231.41.57 06:45, 20 November 2005 (UTC)

[edit] What if...

Ever thought about what would happen had the Pleistocene megafauna (e.g. the giant ground sloths, mammoths, and the such) never became extinct, so the next 10,000 years involved us alongside these giant animals? What could come from this alternative history?

  • We would have different facts in our artiAAARRRGGGH!

(SEWilco 04:11, 7 August 2005 (UTC))

  • Well, I figured that much. I was contemplating actually more realistic impacts, like on human societies and the such.

[edit] End date

"The Pleistocene has been dated in 2005 by the International Commission on Stratigraphy (a body of the International Union of Geological Sciences) from 1.806 million (±5,000 years) to 11,550 years before present[1], with the end date expressed in radiocarbon years. It covers most of the latest period of repeated glaciation, up to and including the Younger Dryas cold spell. The end of the Younger Dryas has been dated to about 9600 BC (11550 calendar years BP)."

Problem: 11,550 years before present in radiocarbon years does not equal 11550 calendar years BP. The correct date seems to be exactly 10,000 radiocarbon years BP or 11,430 ±130 calendar years (BP?), acc to GeoWhen[1]. Do I have this right?

You are correct. It is 10,000 radiocarbon years BP. Bejnar 20:00, 5 November 2006 (UTC)

Query: How can a 2004 publication be the reference for an event that took place in 2005?

  1. ^ Lourens, L., Hilgen, F., Shackleton, N.J., Laskar, J., Wilson, D., (2004) “The Neogene Period”. In: Gradstein, F., Ogg, J., Smith, A.G. (Eds.), A Geologic Time Scale 2004. Cambridge: Cambridge University Press.

Nurg 02:12, 5 November 2006 (UTC)

The data that the ICS confirmed is in the publication. Bejnar 20:00, 5 November 2006 (UTC)

[edit] Pleistocene ≠ Paleolithic

Recent additions to the bloated infobox include cultural levels presented as if they were faunal stages. Shouldn't Paleolithic human cultures be included as a subsection here instead, with a Main article... heading? --Wetman 21:59, 25 February 2007 (UTC)

I'd support that. At a minimum, the things in the infoboxes need to be made consistent with the facts as written in the corresponding articles - e.g., the Mesolithic (and both Kebaran and Natufian) is described as part of the Pleistocene but is in Holocene in the box; until I changed it just now, Paleolithic was listed in the box as Holocene, when it is actually Pleistocene and maybe partly Pliocene. Lots of inconsistencies. Cheers Geologyguy 22:12, 25 February 2007 (UTC)

[edit] Glacial Ice Picture

I was a bit unsure at first, but then I checked a recent atlas and determined that the Union of Soviet Socialist Republics did indeed dissolve in late 1991. Does anyone, parchance, have a more recent picture displaying the maximum extent of glacial ice in the north polar area during Pleistocene time? It is no big deal, but you have to admit, it's a tad absurd to continue having that picture up. Aufs klo 23:28, 16 May 2007 (UTC)

[edit] Incorrect stratigraphy

The Pleistocene is NOT part of the Neogene. The Pleistocene constitutes with the Holocene the Quaternary that follows the Neogene. The last publication of the Geological timescale is only a proposal and is erroneously cited by many people (as is the case on this page). This proposal is not ratified by IUGS and, therefore, not valid yet. The Geological Timescale before this proposal is still valid, so the Cenozoic Era is composed of the Paleogene, Neogene and Quaternary! --Tom Meijer (talk) 11:14, 21 February 2008 (UTC)

I am rather astonished, embarrassed, about the mistakes and incorrect information on this page. I'm not very at home in this wikipedia but in the Dutch wikipedia we should place a message in big lettering that this page contains incorrect information!!! I'm afraid this page needs to be rewritten, at least parts of it.--Tom Meijer (talk) 11:24, 21 February 2008 (UTC)

[edit] We are still in the Pleistocene!

It seems ridiculous, not to mention showing the usual civilized hubris, to create a special "geologic" age to accommodate us the civilized humans, roughly speaking. Is anyone working on fixing this embarassment? The Holocene is the latest interglacial. There will be another glacial in a few thousand years. Nothing changed 10,000 years ago. I have seen scholars tapdance around this, gradually distancing themselves from the idea, and using Holocene as the interglacial name. About time someone took this one up, no? —Preceding unsigned comment added by V.B. (talk • contribs) 16:05, 26 May 2008 (UTC)