Talk:Archean/Archive 1
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Archive 1 |
Untitled
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)
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)
"Life" section needs to be trimmed radically
I plan to remove or radically condense much of the material in the "Life" section over the next few days -- I thought it would be prudent to allow input here before starting. Not only is the mass of material here on the origin of life a disorganized mess, it doesn't even belong in this article beyond a brief summary -- the abiogenesis article is the place for a detailed treatment of that topic. Looie496 (talk) 12:26, 31 October 2015 (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)
"Life" section needs to be trimmed radically
I plan to remove or radically condense much of the material in the "Life" section over the next few days -- I thought it would be prudent to allow input here before starting. Not only is the mass of material here on the origin of life a disorganized mess, it doesn't even belong in this article beyond a brief summary -- the abiogenesis article is the place for a detailed treatment of that topic. Looie496 (talk) 12:26, 31 October 2015 (UTC)
Viruses
"No fossil evidence has been discovered for ultramicroscopic intracellular replicators such as viruses." But didn't the genetic makeup of viruses suggest that they derive from the very earliest life forms? That virus-like creatures/entities were a middle stage between mere organic compounds and the first cellular beings? [probably not - since they are parasitic on cellular DNA they could not have arrived prior to their hosts. Books like the recent (2016)]A New History of Life have remarked this] I know there is no fossil evidence to back this up, and I'm not a biologist, but we might want to add that such things as viruses are thought to have been around throughout the Archean. Steinbach (talk) 17:06, 17 January 2016 (UTC)
- Viruses by definition are entities that don't contain all the machinery necessary for replication -- they rely on their host cells to provide the machinery they lack. Thus viruses can't exist without host cells. It is possible, and perhaps likely, that there was a middle stage of complexity comparable to modern viruses, but they could not have been actual viruses: actual viruses can't exist without hosts. Looie496 (talk) 15:47, 18 January 2016 (UTC)
- I know all this, but my point is: viruses are believed to have existed in the Archean, shouldn't the article mention this fact? Steinbach (talk) 17:51, 18 January 2016 (UTC)
- Sure, if we can reference a reputable published source that states such a belief. Looie496 (talk) 02:25, 19 January 2016 (UTC)
- I know all this, but my point is: viruses are believed to have existed in the Archean, shouldn't the article mention this fact? Steinbach (talk) 17:51, 18 January 2016 (UTC)
Start date for Archean
Red Planet X (Hercolubus) has been editing the start date for the Archean to be 3800 Mya, both in this article and in Template:Geological history. When I reverted, and asked for a reliable source, the editor provided a toolserver URL and reverted me. The current state of the article is now self-contradictory: it states both 4000 Mya and 3800 Mya.
Toolserver is not considered a reliable source (see WP:CIRC). There is a reliable source given in the article: the International Commision on Stratigraphy lists 4000 Mya as the start, as of 2013 [1]. Is there a better reliable source for 3800 Mya? —hike395 (talk) 20:04, 12 January 2017 (UTC)
- I agree with Hike. The article cites the ICS chart as its source and we must follow it both because we have cited it and because it is the definitive offical source. Dudley Miles (talk) 22:15, 12 January 2017 (UTC)
- Oh! Thanks for telling me! — Preceding unsigned comment added by Red Planet X (Hercolubus) (talk • contribs) 12:01, May 2, 2017 (UTC)