Talk:Archean

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if it's an antiquated term, what is it called now?

I'm not sure at all it is an antiquated term, it is listed in the GeoWhen database too. And what is more important, it is not part of the Proterozoic eon. Archean is an _eon_ of its own, as well as Hadean and Phanerozoic. That should be mentioned in the article. Jyril 22:00, 9 Jul 2004 (UTC)

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The Tree of Life link is not very good -- it goes to a religious article. Falatwar

Percentage of cratons of Archean age

Question: "...7% of the Earth's cratons formed during the Archean" --Does anyone have a value for the percent of continental outcrop/surface rock that is Archean? Or is that what is meant? Fantastic referencing, btw, thanks. Andesite 22:56, 11 January 2007 (UTC)

Good question - I spent some time trying to find a validation or explantation of that figure, and could not; perhaps someone who has access to the Stanley book can do so. My guess is that the 7% figure refers to some estimate of the actual extent of Archean vs other rocks, and that the amount of outcrop of Archean rocks would be even less. But I definitely do not know for sure. Cheers Geologyguy 00:13, 12 January 2007 (UTC)

Origin of word?

What is the origin of the term "Archean"? I really want to konw. —Preceding unsigned comment added by 76.102.227.227 (talk) 00:08, 12 February 2008 (UTC)

It's from Greek, "arche" - the same root as in archaeology and archetype. The word would translate as "primeval age". /Strausszek (talk) 23:49, 1 September 2009 (UTC)

Origin of the oceans?

I notice that neither this article nor Precambrian says anything much about how the water bodies of the oceans formed. The oceans are essential to life on earth and to most other facets of the planet so this really is an oversight. The traditional consensus among geologists is that the primeval ocean came into being through many millions of years of heavy rain out of thunderous skies, which finally established a world-wide sea, a few km in mean depth (that's a very intriguing picture isn't it?) Could somebody check if this is still how scientists visualize it? /Strausszek (talk) 23:49, 1 September 2009 (UTC)

Timeline

Someone needs to correct the timeline, ha ha it begins in the paleozoic 540,000,000 BC and goes to 4.5 billion years before that or 5 billion years ago before the earth formed. I believe it is 10x off — Preceding unsigned comment added by 174.253.209.11 (talk • contribs) 22:29, 4 March 2011

Archean earth

Missing NOUN, I think. I'd suggest "mass" - but that's strictly based on context. Maybe "volume," because of "present volume" earlier in the sentence.

The other school follows the teaching of Richard Armstrong, who argued that the continents grew to their present volume in the first 500 million years of Earth history and have maintained a near-constant NOUN ever since: throughout most of Earth history, recycling of continental material crust back to the mantle in subduction or collision zones balances crustal growth. (Minas Beede, not logged in) 184.60.28.251 (talk) 03:24, 12 September 2011 (UTC)

What are the limiting events?

It should be mentioned what exactly are the events that mark the limits of the Archean eon. What happened at its beginning, and what at its end, that justifies considering these boundaries as eon boundaries? -- 77.189.29.100 (talk) 14:42, 23 October 2011 (UTC)

A good question, I'll need to check, but I recall that that the only things that survive that were formed during the Hadean are certain mineral grains. The oldest Archean rocks are the oldest parts of the earth that exist actually as rock (even if some of them are only a few square kms across). The Proterozoic is named for 'early life' and contains the first record of cyanobacteria and the stromatolites that they formed. I'll see if I can dig something out that supports my rusty memory. Mikenorton (talk) 15:09, 23 October 2011 (UTC)

can't read colors

This entry is very unfriendly to the colour-blind. I can hardly read any of the chart at the right. StevinSimon (talk) 03:22, 25 February 2012 (UTC)

It is hard enough to read the blue against dark colours for non colour blind people. What do you think about a white background for the text? Graeme Bartlett (talk) 10:47, 26 February 2012 (UTC)

Ma? Mya? Ga?

Why are we using such arcane abbreviations? Can some knowledgeable person kindly put them into English? Thank you. GeorgeLouis (talk) 14:39, 7 October 2013 (UTC)

While I'm at it, how come there are no commas in the chart reading "4000 - 2500 million years ago"? And there seems to be no way to get in there to fix it. GeorgeLouis (talk) 14:46, 7 October 2013 (UTC)

• I have changed that odd Mya to Ma (magaannum=million years ago) but erhaps only using Ga is appropriate. In the first use of these there is an explanation in parenthesis. I am unconvinced that you need a comma in 4000. Graeme Bartlett (talk) 11:54, 8 October 2013 (UTC)

You use figures without commas to refer to years, like 2013. A number is 2,013. Thank you for paying attention. I like WP articles to be understandable to the average high school student. Yours, GeorgeLouis (talk) 01:18, 12 October 2013 (UTC)