Talk:Craton

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[edit] Quality of Second Image

Can anyone make a replacement for the second image on this page? No offense to its creator, but it appears unprofessional and not very legible. --Gadren 00:05, 26 April 2006 (UTC)

I posted the "North American cratons and basement rocks" image because it clearly shows the locations of the Slave, Rae, Superior, and Wyoming Cratons, as well as the Grenville Belt and the Yavapai and Mazatzal accretions, although unfortunately it does not show the Mojave accretion. It could be better, and I wanted to enlarge it to make it more readable, but couldn't; however, the contrasting colors clearly delineate all the North American cratons listed. If someone can come up with a more detailed map then I think it would have to be enlarged to be readable.

Actually, we need a much better first image. The initial image shows the shields, platforms, orogenies, and extended crusts, but not the cratons. We need a world map image that shows the locations of all the cratons. --Valich 03:43, 27 October 2006 (UTC)

[edit] Craton vs. the process of cratonization

To conform to Wiki Manual of Style, would it be better to link the "cratonization" process to a separate article? I don't think the article, nor the subject, has the depth or complexity to justify two articles. They're too closely related of a subject.Valich 07:09, 9 September 2006 (UTC)

I think because they are so closely related that the previous version was better, where "cratonization" was in a labeled section which separated the process from the "definition" and "listing" sections. The explanation of the creation of cratons can also help people to understand details which are not apparent in the short definition. (SEWilco 07:17, 9 September 2006 (UTC))

Added header and also indented and fixed the long direct quote. Probably needs to be rewritten rather than added as quote. Vsmith 12:32, 9 September 2006 (UTC)

[edit] First illustration

I puzzled over the first map. It shows platforms and orogens etc without explaining how these fit into the classifications (archons, protons etc) given in the text. The only ages given for the map's areas are for the young ocean crust. Delete the map or explain it. JMcC 08:34, 14 September 2006 (UTC) A top portion of a craton consists of both a shield and a platform, and this is stated in the article as well. If you look at all the shield and platform areas of the first illustration, they do correspond nicely with the locations of all the cratons, and therefore it is of some help. Cratons, however, are not classified into groups called archons, protons and tectons, and I have never heard references of the provinces of cratons classified as such. So I have no idea where this classification scheme came from, unless it is something new in the literature. These are terms that I have never come across in any articles on cratons and unfortunately whoever added this classification scheme has given no source. I suggest that unless the term province be further clarified, that this classification scheme also be deleted or clarified and given the source of whose classification scheme this is.

Cratons consist of a shield, the surrounding platform and a crystalline basement and are subdivided geographically into geologic provinces. I agree that we do need a better first illustration that clearly shows the locations of the cratons of the world. The first illustration could then follow as a further illustration of the location of the constituted parts of a craton and what the other continental land masses are referred to as, i.e., orogenies and extended crust. --Valich 22:54, 29 October 2006 (UTC)

[edit] Hamilton is minority view

(moved to Talk from article by SEWilco 15:02, 13 October 2006 (UTC))

Editorial note: The process of craton formation is extremely contentious. The paper by Hamilton (1999) is, if anything, even more contentious, and represents a minority view that is not generally endorsed by the geological community. An even-handed summary of the leading theories of craton formation (thrust stacking vs deep mantle melting events) is required here - and this is not one of them. Furthermore, I wonder if "succulent" is an appropriate descriptive term for scientific writing. 137.111.13.34 03:38, 13 October 2006 (UTC)Dr C. O'Neill, Geodynamicist, Macquarie University

Yes, Hamilton's view is just one possibility. Article has been changed to state this. I also cautiously agree that it is a minority view, but any viewpoint beyond the 3.5 Ga range and beyond into 4 Ga is speculative. I added the entire "Craton Formation" section because I found no other reference to how cratons are formed in any other source. This section definitely does need to be improved, and better established viewpoints would certainly be a great asset. If you have a source, then please add it in. --Valich 04:00, 27 October 2006 (UTC)

[edit] United Plates of America

My edit was removed on the basis that "out of place bit - just because one website uses a "catchy" phrase doesn't make it notable)". If it was true that there was only one web site using that name, I would not mention it. But a scholar.google.com search returns 242 entries and a main google.com search returns 335 entries. So to me the phrase is in general enough use to be included. By contract "Congo craton" has 992 hits and "angara craton" 60. The "Congo craton" has it's own wikipedia page.

Perhaps instead of just listing one craton name, this page should be enhanced with a list of them? http://www.answers.com/topic/craton has a list. In a list, "United Plates" could be used as another name for the North American craton.

Jerryfern 02:34, 13 December 2006 (UTC)

The placement of that "name" and link at the end of a general discussion of cratons was indeed out of place. I haven't analyzed the google hit for the phrase to see who is using it - catchy phrases do tend to get picked up by websites - the in thing to do. Whatever, it still doesn't belong here. There is a list of cratons - see List of Platforms, Shields and Cratons and North American craton is listed there (it redirects to Laurentia). Your catchy phrase if it can be shown to be used as more than just a catchy phrase could be mentioned in the Laurentia article perhaps. Notable usage would be required. Vsmith 03:19, 13 December 2006 (UTC)
Wonder where www.answers.com got its list? ;-) Cheers, Vsmith 03:23, 13 December 2006 (UTC)
OK - googled a bit - almost all of the relevant hits were to the following article:
Hoffman, P.F., 1988, United plates of America, the birth of a craton; Early Proterozoic assembly and growth of Laurentia: Annual Reviews of Earth and Planetary Sciences, v. 16, p.543–603.
Either bibliographic links or refs to the article by Hoffman.
A significant number of hits were to the same title - referring to liscense plate collecting and Ebay listings ... as well as some gourmet food bits (dinner plates I guess).
As roughly half of the hits are to that one relevant article by Hoffman - it seems maybe worthy of a wiki article of its own. Now to see if I can get a copy - sounds like an interesting read. Thanks for bringing it to my attention (as if I needed more to read:)
Still doesn't fit in this article though. Vsmith 03:44, 13 December 2006 (UTC)

Fair enough. Your points make sense. But shouldn't this article point to the other wikipedia craton pages? Google search of 'craton site:wikipedia.org turned up a bunch. Thanks. Jerryfern 04:52, 13 December 2006 (UTC)

Hoffman's paper is important and almost seminal in its continent-scale analysis of cratonic elements of North America. Interpretations have changed since 1988, of course, especially for things further back in time, but much of his basic framework is still cited (as Vsmith's googling shows) and it is still important. Geologyguy 16:12, 20 December 2006 (UTC)