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DYK nomination

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Hmm... I would assume you meant "one shield" rather than "on shield"? Typos are fun. Vsmith (talk) 14:06, 21 April 2013 (UTC)[reply]
They are ;). Fixed it. Thanks. --Tobias1984 (talk) 14:10, 21 April 2013 (UTC)[reply]

Canadian shield

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I've removed the following:

province of Grenville sedimentary rocks metamorphosed into marble, quartzite, and gneiss and later intruded by granite and gneiss.<ref name = Wallace1948>{{cite web|title = Geology of Canada|last = Wallace|first = Stewart|date = 1948|url = http://faculty.marianopolis.edu/c.belanger/quebechistory/encyclopedia/GeologyofCanada.htm|accessdate = 10 Mar 2013}}</ref>

and replaced it with a rather simple introductory sentence.

The sentence removed was rather garbled and sourced to a 1948 book which was written in the 1930s. The problematic ref was written before current understanding of Precambrian geology, we shouldn't depend on ancient sources. Vsmith (talk) 20:21, 26 April 2013 (UTC)[reply]

Section Names

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Tobias asked me to come in and look over the names for geological versus physiographic origin (or is it orogen?). Now, it's difficult to come up with good names for the orogens, as many underwent numerous orogenies. The names I used came mostly from [1]. As for actually changing the names: the coast section under American Cordillera could easily be renamed Active Margin, besides that, names get harder. Sevier Belt, Laramide Belt, Sevier-Laramide Belt, and Sevier-Laramide Orogen all return some google results, like this [2] and this [3] and could replace Rocky Mountains, but I don't know that any could be considered common. Besides which, the Laramide Orogeny also occurred in the Sierra Madre and the Basin and Range. The Appalachian Mountains appear to have no well known orogenic name, the Grenville Orogen should include parts of Mexico and the Ouachita Mountains, and intermontane province appears interchangeable with basin and range province, neither of which is truly geological, although basin and range at least is telling about the origin of the province. Southern Cordillera is not even really a province name, as that section needs expansion so that it divides up the Sierra Madre Occidental Ignimbrite province, the Sierra Madre Oriental Fold and Thrust Belt, the Trans-Mexico Volcanic Belt, and the Jalisco Block, Chortis Block, and Chorotega Block. Overall, I feel as if I have written too much to say nothing useful. --Al Climbs (talk) 17:09, 27 April 2013 (UTC)[reply]

Alright, I put a little more thought into it. Appalachian fold and thrust belts has some google hits and is suggestive of the geology. [4] provides a good map of the canadian shield provinces, taking after Hoffman1988 (also in [5]), if we want more detail there. On the West coast, Fuentes [6] uses the North America Cordilleran orogenic system instead of American Cordillera. Decelles [7] uses Laramide Belt for the Rockies and reserves Sevier Fold and Thrust belt for the mountains from the Canadian Rockies through the Tetons and Unitas. This would take more division of the Cordillera than we have or have space for. Perhaps we could use Laramide Fold and Thrust Belt, Laramide Foreland and Sevier Fold and Thrust belt, and the Active Margin, for the Rockies, Intermontane, and Coast Ranges.--Al Climbs (talk) 21:51, 28 April 2013 (UTC)[reply]
I know too little about the North American Geology to be really helpful, but looking at your sources I would say that "Rocky Mountains" is both a geologic and geographic term. I really don't understand how they are grouped and subdivided, but maybe I can do some reading on the weekend. --Tobias1984 (talk) 05:34, 29 April 2013 (UTC)[reply]
I am confused about what you are trying to do? The orogenies and the mountain belts already have names. Why don't you use those? You want to rename the Coast Ranges and the Rocky Mountains? Why? This article is very unclear. -68.107.137.178 (talk) 04:06, 1 May 2013 (UTC)[reply]
I don't know how how much you know about geology. So I hope I am not answering this at the wrong level of understanding: The Alps for example are a geographic term for a connected mountain chain. In regional geology they are split into the Western Alps and Eastern Alps because they are the products of two different continental collisions. The geologic and geographic definitions are always different. The thing is are the differences large enough for an encyclopedic entry. --Tobias1984 (talk) 07:28, 1 May 2013 (UTC)[reply]
I'm a paleontologist, so, I'm a geologist. -68.107.137.178 (talk) 08:11, 1 May 2013 (UTC)[reply]
Excellent. I think in that case my answer would be that right now our subdivisions are a little unsourced. In the Geology of Russia entry we had a couple of books that had chapters after which we named the headings. There is one book about the regional geology of north america which I have yet to order and read. Maybe your library has it? It would shed some light on how the subdivisions of regional geology are commonly drawn in North America.
By the way: Why don't you sign up for an account. With 20k+ articles in the earth sciences we can always use people that are interested. Also sign up here if you like: Wikipedia:WikiProject_Palaeontology ;) --Tobias1984 (talk) 08:39, 1 May 2013 (UTC)[reply]
They are more like completely unsourced, and you appear to be making up names for mountain ranges, you don't consistently use the same term for the same thing, your maps don't use the words you use, you have titles that don't include any content about the title, your paragraphs are jumbles from Proterozoic to Mesozoic to Paleozoic, you mix up modern structures with ancient processes as if they are the same thing. This article is completely unreadable and should be gutted in its entirety until the editors figure out what they are talking about. What book? I'm a geologist, my library has hundreds of books about the regional geology of North America. Do you have an ISBN? One can edit without an account. Not interested. -68.107.137.178 (talk) 08:56, 1 May 2013 (UTC)[reply]
I already said that the article needs work. And that is no reason to gut it. If you want to improve the article, improve it, otherwise you have to move on. Complaining about the quality is OK, but all of our editors have a work load you probably don't want to imagine. So you have to take into account that this might take months. The book I was talking about is in the "further reading" section. --Tobias1984 (talk) 09:04, 1 May 2013 (UTC)[reply]
If the article is original research combined with meaningless nonsense, it should be gutted, if gutting it will both improve it by removing OR and nonsense which should not be in Wikipedia and should not be mirrored all over cyberspace. All of your editors don't have an unimaginable workload, Wikipedia editing is purely volunteer, and if editors impose upon themselves ridiculous workloads such that they create OR nonsensical essays that are mirrored all over cyberspace they need a wikibreak, not continued editing that puts Wikipedia in disrepute creating scenarios like male-only top categories. Months of spreading this into cyberspace is inexcusable. If it is so precious it can be userfied in the meantime. The DNAG books would be a good basis for outlining the article, but not the only basis. Geological provinces of North America are pretty standard. -68.107.137.178 (talk) 14:29, 1 May 2013 (UTC)[reply]
If you can't point out the sections that you are calling original research I will dismiss this criticism. And yes even volunteers have workloads. There are thousands of articles that are not up to date, incomplete, have mistakes etc.. That doesn't mean that Wikipedia is spreading lies. Wikipedia is a place to inform not to contain scientific truth. If you need scientific truth you have to read peer-reviewed journals. --Tobias1984 (talk) 21:09, 1 May 2013 (UTC)[reply]
I already did; you appear unwilling to read it. This whole discussion session is based upon your attempt at creating original names for mountain ranges. So, you're spreading random guesses, that's better? It's not. If you don't know the names of the mountain ranges, don't go looking for making up names and creating new ones. If there is nothing in the literature that gives it a name, it's not got any literature about it. Volunteer workload? Forced upon yourself? There's not really much I can say about claims that Wikipedia editors are so busy due to self-enforced workloads that they are not too concerned about getting things right according to the sources. It's ridiculous. If you can't follow the sources, you should not be writing it, not creating some imaginary force upon yourself to do more. -150.135.210.102 (talk) 22:43, 1 May 2013 (UTC)[reply]
I don't exactly understand why this is happening, but I will give a quick response to a misunderstanding I think is occurring. The current names are not unsourced. They occur in the reference that I provided when I said "The names I used came mostly from [8]," a book by a reliable source, namely a professor of geology Eric Christensen of BYU and others. The difficulty is that those names are physiographic not geological, and we would prefer to use geological names. In response to maps and the names they use, we only use two maps, and both appear to use the same names as we use to me, North American Craton and the provinces of the Appalachians. I am somewhat confused what is original research. We are specifically not creating original names, at least I am not; we are attempting to conform to a policy that we use geological names, and not physiographic. To conform with WP:No Original Research each name I suggested is supported with at least one of what I believe to be a reliable source following it. If there is original research in the article that should be pointed or removed. At minimum it needs to be tagged. We are concerned with getting things right, that is why I opened this conversation with two paragraphs and seven sources, which appear to have been ignored. The purpose of this talk was intended to be to help find which sources to follow, that does create some difficulty in finding sources. If there are concerns other than the geological names, I would recommend opening a separate section in this talk page for discussing them. Can we please return to the topic of which of the names from reliable sources to use?--Al Climbs (talk) 04:17, 2 May 2013 (UTC)[reply]
@AlClimbs. "Unsourced" was a bad choice of words on my behalf. What I meant is that there is some uncertainty (also on my behalf) how these terms are used in geology. I ordered the book from the further reading section and can get back to you in about one or two weeks. --Tobias1984 (talk) 07:06, 2 May 2013 (UTC)[reply]
In case you want to start now on the Precambrian see this. Cheers, Vsmith (talk) 10:30, 2 May 2013 (UTC)[reply]
Thanks for the link Vsmith. From what I've read so far I can't find any instances of original research and our chapters don't look "made up" to me. Thank you for helping out too. --Tobias1984 (talk) 16:58, 2 May 2013 (UTC)[reply]
I was responding mostly to the comment "They are more like completely unsourced, and you appear to be making up names for mountain ranges," when, as far as I can tell, that is not at all true. I'll wait to see what happens to this article. Maybe, in the meantime, we could pull up some drafts of sections based on the current sources (which as far as I know are good)? --Al Climbs (talk) 07:13, 2 May 2013 (UTC)[reply]

You're picking names from google searches? How isn't this original research? Find sources that list the main names and use those and cite the source. You also, as I pointed out, call an entire section "North American Craton," but then use shield instead of craton in parts of the article, after never bothering to define what the North American Craton is. This is a general encyclopedia. If you're going to divide the continent into geological provinces, divide according to a citable source, then define each region, then subdivide and go for the geology in a logical and geological fashion in a way that allows the reader to understand. Describe the region first, its boundaries, its major features, then explain, travelling through time, how those features came to be and lastly, attach those features to the features of surrounding regions. The continent is also not just about the structure and tectonics, it's about the rocks and cover, the great faults and sutures, the juxtapositions

Also, the regional geology article hints of confusion about what regional geology is, it's just large scale, sub-continent, supra-outcrop. It is not the geologically unrelated geology of an area described by political boundaries. -68.107.137.178 (talk) 01:33, 5 May 2013 (UTC)[reply]

Your right, an overview section would be appropriate. - I personally think that web searches are a great research tool. Wikipedia is also about what most sources say, and the easiest way to estimate that is how often a term is used. - By the way: German and Dutch Wiki don't have any citations for Regional Geology, which I think should be seen as the difficulty to find appropriate sources for this topic. --Tobias1984 (talk) 07:20, 5 May 2013 (UTC)[reply]
Wikipedia relies upon reliable sources not popularity contests. Names should reflect the most common name, but you can't find that by guessing at a series of names that might be in common usage; for a scientific subject, you should start with sourced names, then you can do searches and see if one is more commonly used than others. Other editors disagree with this title by google policy, but it's fine to decide what is in most common usage, imo. But if you're randomly guessing at what things are called and your primary sources are a book you don't have and a 25-year-old book in a foreign language that is of such limited availability as to suggest it is no longer in favor (even in German), then you're probably not at the point where you're debating which of the citable names is in most common usage. There are no lack of sources for regional geology; I just grabbed the first structural text off my bookshelf to add a source to the article. what difference does it make if German and Dutch Wikipedia don't have sources? I am pretty far from understanding this conversation. Regional geology is not an obscure term. -68.107.137.178 (talk) 08:21, 5 May 2013 (UTC)[reply]
I would agree with you that it would be original research if I had been picking random names and googling them, luckily that is not what I was doing. At least not with most of the names that I suggested. For the most part, I was going through resources already on the page and seeing what they used, googling for that, seeing what came up, and seeing what else they used, E.g. Laramide belt is used in English (2003), a refernce already on the page. Several maps I saw used the combination of sevier belt and Laramide belt. Anyway, it wasn't random guess, although it might be argued that I showed bias to the references on the page, whatever that means.--Al Climbs (talk) 21:04, 11 May 2013 (UTC)[reply]
It looks like you are simply guessing with your comments about Sevier and Laramide. They are not synonyms and neither is a synonym for the Rocky Mountains, either singly or jointly, and of all possible combinations, only the one could be argued in any way as a synonym; so, it's hard for me to not suppose you are simply randomly entering names into Google searches. You also can decide with this whether to separate the Rockies from the Cordillera, depending upon how you described Sevier and Laramide overlap, but you can't just randomly say that "Sevier Belt, Laramide Belt, Sevier-Laramide Belt, and Sevier-Laramide Orogen all return some google results, like this [2] and this [3] and could replace Rocky Mountains" because it makes no sense and leads me to assume that you are just picking random names and googling them without any concept of what they are. I don't know how to refocus conversation that is so far off base. -64.134.239.159 (talk) 05:49, 13 May 2013 (UTC)[reply]
It would probably help if you would name your sources and explain how you would structure the article. --Tobias1984 (talk) 06:54, 13 May 2013 (UTC)[reply]
I also noted in that same section that none of the terms I suggested are considered common, and that all vary in geographical extent from that usage when I said that "the Laramide Orogeny also occurred in the Sierra Madre and the Basin and Range," I just was trying to find Orogenic names based on the current sources. The next section I try to clarify things, but I live in the Front Range right now, so I use the term Rocky Mountains to mean Front Range at times, as well as various other things, which probably confuses everyone. Note that I wrote "Decelles uses Laramide belt for the Rockies" when I had already noted that the Laramide orogeny is more extensive. Overall, my localized language and my inability to find sources in agreement confused everyone. If you want to comment on what's happening, I reused your suggestion of just using the Decade of North American Geology from the GSA(I think that was lost on me amid all the other confusion happening in this conversion) and put it forward.--Al Climbs (talk) 19:40, 13 May 2013 (UTC)[reply]
Then let's just move forward with an outline from DNAG. We can supplement Laramide and foreland basin and fold and thrust in the Cordillera with DeCelles as needed, but the DNAG outline is readily available, stable, respectable, and a good start. -166.137.209.165 (talk) 21:58, 13 May 2013 (UTC)[reply]

Forgot to say, does anyone actually have suggestions on what to do about orogenic names? I would like to return to what this discussion was supposed to be about. If you like any of the names I suggested here, we should discuss them. I found a series of articles published by the GSA from 1986 to 1993 called Geology of North America or Decade of North American Geology that appear to be good resources. Lots of names similar to what we use, e.g. Cordillera, Basin and Range, Interior Platform. They also appear to be good resources on the particular regional geologies, as each in the "series" was actually a volume published on a particular topic. The overview provides two different sets of names (I guess even the authors cannot agree with themselves), and if anyone is interested I will reproduce some here.--Al Climbs (talk) 21:10, 11 May 2013 (UTC)[reply]

I think we should use standard names for orogenies and carefully distinguish processes and resultant landforms. The reader will then have the info they need to look up more in-depth material. I am not certain, but I believe there is some confusion in this discussion due to mixing up the names of the names of the mountain building processes through time and the names of the mountains (or vice versa). -166.137.209.165 (talk) 20:20, 12 May 2013 (UTC)[reply]

Further reading -- choices, readily available English on topic, or obscure, German when there are hundreds of available books in English

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"The further reading section of an article contains a bulleted list, usually alphabetized, of a reasonable number of works which a reader may consult for additional and more detailed coverage of the subject of the article."

Why are you including an obscure, German language text when there are hundreds of available sources in English? Have you looked at this book, and, since I assume you own it or something, and are therefore recommending it, what is so fantastic about it that it should trump books that actual readers of English "may consult for additional and more detailed coverage?" And what does this book use as province titles, why not cite them? There doesn't appear to be much room for regional scale geomorphology in the article, so, what is relevant in this book for this article?

And, since I already disgreed, why not discuss it first before reverting, or simply include your reasoning behind using this book? Any information at all, since it is such limited availability in a foreign language, let readers know what they should consult this book for. -68.107.137.178 (talk) 08:15, 5 May 2013 (UTC)[reply]

Googlers 1, Geologists 0, the usual round score

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Okay, the article is yours. It's badly written, it's contradictory, it's confusing, and it's wrong. But it's yours. -68.107.137.178 (talk) 08:37, 5 May 2013 (UTC)[reply]

Disputed

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Read above. Read the article. The editors don't want it edited, yet keep putting Hawaii on the North American Plate, don't explain what the North American Craton is, yet pick that as the title for the section, don't know what to name the sections or call them, the article uses shield as a synonym for craton, does not explain this, it is tied to a DYK that says there is only one shield, but then names other shields. It's too confusing and badly written to even list all the disputes, because it is impossible to understand the article as it jumps from general to specific, all over the place in time and space. You need something far more coherent to go through it sentence by sentence. I dispute the entire content of the article as badly written and garbled and incomprehensible and wrong. -64.134.230.142 (talk) 00:33, 7 May 2013 (UTC)[reply]

Rather than arguing and insulting other editors, why not jump in and add/fix the content. You say above that you have a geological background ... show us by adding some solid, referenced content. And ... I don't see Hawaii mentioned in the article. Yes, the article needs improvement (as do most articles) - so get on with it. Vsmith (talk) 01:02, 7 May 2013 (UTC)[reply]
My fixes are reverted. I removed Hawaii, from the North American Plate in this article and from the Cordillera on the North American Plate in the other article. It takes, what, two weeks of arguing to fix the fact that the section about the North American Craton doesn't mention what it is, uses shield as a synonym, then the DYK says there is only one shield, but the article lists more than one craton? The article as is, is incomprehensible; fixing this is like trying to put a raw egg back together; you need to start with a fresh egg, outline the topic, develop each section methodically. The North American Craton is, then the divisions, then move from general to specific, then give some examples, but since this article is so jumbled up in time and space, an editor cannot correct parts, gluing pieces of the shell together is not going to get you an egg, even if they had the patience to deal with one or two sentences each week, with paragraphs of discussion and reversions and threats of blocking for edit warring along the way. -64.134.230.142 (talk) 01:15, 7 May 2013 (UTC)[reply]
What "fixes" are reverted? I see a couple of minor edits by 68.107.137.178 and removal of Hawaii bit on 21 April and another Hawaii removal on 1 May. Where were you reverted? (other than tags and trivial further reading book? What substantial improvements have you made to the article? Seems that if you pick a section and make substantial referenced improvements, you would make some progress. So, simply stop the incessant arguing, insulting and seemingly trollish behavior: jump in and improve the article. Moving on ... Vsmith (talk) 01:44, 7 May 2013 (UTC)[reply]
Not as badly as I am wasting mine, Randy in Boise, or as badly as this article is wasting everyone's time by having it live and in main space showing up as number 1 in Google searches. We'll see. -64.134.230.142 (talk) 01:56, 7 May 2013 (UTC)[reply]

The Hawaii reference is gone for good, it seems, and we have cleared up the craton issue. Is there any other reason to keep the disputed tag now? RockMagnetist (talk) 02:07, 8 May 2013 (UTC)[reply]

Although I still have concerns about the article, I see that editors are working on it, and I feel that with this accomplished, editors improving the article and being allowed to improve it, the tag can be removed. -68.107.137.178 (talk) 02:25, 8 May 2013 (UTC)[reply]

What is a craton

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Editors seem lost here. The ancient stable part of the continent is the craton, consisting of shield and the greatly covered platform. This article uses shield as a synonym for craton, which is actually okay, but now it is using craton as a synonym for platform in addition. This is confusing, and it is not really okay to use craton as a synonym for platform or vice versa due to the nature of the platform area of the craton.

Please define craton, then divide into shield and platform in that order. -[[Special:Contributions/198.228.216.175|198.228.216.175](talk) 14:56, 7 May 2013 (UTC)[reply]

I would like to see that relation clarified too. Shouldn't Geology_of_North_America#North_American_Craton_2 be titled something else? A summary statement at the top of Geology_of_North_America#North_American_Craton would help. Also, is North American Craton really used as a name? My impression is that it is usually referred to as "the North American craton". Finally, is the article on Laurentia correct in saying that Laurentia is a synonym for North American Craton? Or is Laurentia reserved for the times when it was a separate continent? RockMagnetist (talk) 23:02, 7 May 2013 (UTC)[reply]
Seems my attempt mucked it up a bit, so I've undone until I have more time to do it justice. As for the current redirect of North American craton to Laurentia, it does seem problematic and agree that Laurentia should discuss the historic continent, but that's a discussion for elsewhere. Vsmith (talk) 23:39, 7 May 2013 (UTC)[reply]
I think the relationship between Laurentia and the North American craton should be clarified in this article. For example, it was given as the main article for the platform instead of for the whole craton - I think that's incorrect, so I moved it. RockMagnetist (talk) 23:45, 7 May 2013 (UTC)[reply]
Agree with that. Vsmith (talk) 23:51, 7 May 2013 (UTC)[reply]
Yes, agree with reversion, agree with temporary fix on craton/Laurentia, etc. The usage has been fluid over the years; I think for the purpose of our article we have to define the Craton as the tectonic processes leading to the current stable North American continent upon which the orogenies have attached themselves, and Laurentia as the ancient continent. It is tricky, though, as technically Laurentia exists today as the stable core of the North American continent, meaning it is the craton. I have seen it used both ways. I am not a structural geologist, but rather a sedimentologist; I work lately translating in structural geology, so I can read the technical literature in the field at any level, but I don't have the familiarity of a diverse body of literature in the field that would be necessary to discuss this without a serious literature search dealing with Laurentia, ancient and modern, the North American craton, Greenland through time, etc. I suggest we use North American Craton or Canadian Shield for now, then add the Laurentia information later. -68.107.137.178 (talk) 00:14, 8 May 2013 (UTC)[reply]
I took a stab at writing a summary statement for the section. I'm not Randy from Boise, but I'm not an expert on North American tectonics either, so feel free to modify it. Is it enough to satisfy your concern about the definition of the craton? RockMagnetist (talk) 00:34, 8 May 2013 (UTC)[reply]
Yes, this is a basic, understandable and, therefore, usable description. I think we can get fancy or sophisticated or elaborate later, but until most of the article is written like this, a straight forward definition or description for the general audience, it is very hard for a reader to get anything from it. Thanks. -68.107.137.178 (talk) 02:04, 8 May 2013 (UTC)[reply]
Glad to hear it. Can we remove that tag then? RockMagnetist (talk) 02:06, 8 May 2013 (UTC)[reply]
There are still major problems, but as long as editors are working to correct the problems rather than maintain them, it's okay by me that you remove that tag, even the other one. -68.107.137.178 (talk) 02:23, 8 May 2013 (UTC)[reply]
O.k., I have removed them. Let me know if you spot any other particularly bad problems. RockMagnetist (talk) 04:16, 8 May 2013 (UTC)[reply]

Caribbean

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Most or all of the Caribbean is on the Caribbean Plate, which makes it unlikely that it is usually included in North American geology. Of course, I could be persuaded by a good citation. RockMagnetist (talk) 00:03, 8 May 2013 (UTC)[reply]

You are correct, and I removed some references to the Caribbean for the time being, however, because of the structure of the forearc between the North American plate and the Caribbean Plate, some aspects of the Caribbean will be eventually added back to the article. You are right to require persuasion via a solid citation, and I think adding it back can wait until it is accompanied by such; it is an exciting area in tectonics right now, so I would hate to omit it, but I think it can run at the end. -68.107.137.178 (talk) 00:06, 8 May 2013 (UTC)[reply]
Decade of North American Geology from the GSA (1986-1993) devotes an entire volume on the Carribean. They also include Greenland with Canada in one of their volumes. I have access to this series if anyone is interested in some summary from it. Anyway, we should probably decide what to include in "North America" sometime.--Al Climbs (talk) 21:23, 11 May 2013 (UTC) correction --Al Climbs (talk) 21:24, 11 May 2013 (UTC)[reply]
DNAG would be my first choice as the leading source for this article, supplemented by review articles from later sources. I did not know there was an entire volume on the Carribean, but it is a minor plate, so that makes sense, in addition to the interaction of the plates. -64.134.239.159 (talk) 05:51, 13 May 2013 (UTC)[reply]

Nordamerika - G. H. Eisbacher

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Here are the chapters of the book "Nordamerika" by G. H. Eisbacher. Hope this helps. --Tobias1984 (talk) 20:05, 11 May 2013 (UTC)[reply]

  • Geologic investigation of North America
  • Geologic provinces and crustal structure of North America
  • Archaic crust
  • Superior Craton
  • Volcano-plutonic greenstone-belt
  • Plutonic tonalite-gneiss-belt
  • Metasedimentary gneiss-belt
  • Highlty metamorphic gneiss-belt
  • Archaic crustal model
  • Archaic ore deposits
  • Proterozoic basins, orogenies and magmatic belts
  • Early Proterozoic basins
  • Huron-Marquette Basin
  • Circum-Ungava Basin
  • Coronation Basin
  • Trans-Hudson Orogen
Middle Proterozoic basins
  • Older great sequence (1.6 - 1.2 Ga)
  • Younger great sequence (1.2 - 0,8 Ga)
  • Middle Proterozoic anorogenic magmatism
  • Keweenawan Rift
  • Grenville Province
  • Early and Middle Proterozoic ore deposits
  • Late Proterozoic Rifts, Paleozoic mio-geoklines, and continental platforms
  • Late Proterozoic Windermere Rift and Paleozoic mio-geokline on the North American west coast (Cordillera)
  • Late Proterozoic-Cambrian Rift and Paleozoic mio-geokline on the North American east coast (Appalachians-Ouachitas)
  • Franklin-Northern-Greenland Basin
  • Continental Platform
  • Four corners region
  • Ore deposits of the platforms and mio-geoklines
  • The Paleozoic orogens
  • The Appalachian-Ouachita Orogen
  • Newfoundland
  • New England
  • Southern Appalachians
  • Ouachita-Marathon Orogen
  • Innuit-Ellesmere Orogen
  • Antler Orogen
  • Ore deposits of the Paleozoic orogens
  • The North American Cordillera
  • Subduction, accretion and collision in the western Cordillera
  • California Coast Range, Klamath Mountains, Great Valley and Sierra Nevada
  • The western Cordillera of Canada and Alaska
  • The western Cordillera of Mexico
  • The metamorphic core complexes
  • Foreland basin and fold-and-thrust belt
  • Ore deposits of the Cordillera
  • Atlantic-Atlantic continental margin
  • Gulf of Mexico
  • The Atlantic continental margin
  • Labrador Sea nd Baffin Bay
  • Sverdrup Basin and the arctic continental margin
  • Neogene geodynamic of the North American west
  • The trans-mexican volcanic chain (Eje Neovolcanico)
  • Gulf of California (Mar Cortez) and San-Andreas strike slip fault
  • Cascades and Chilcotin-Columbia Plateau
  • Alaska and Aleutian
  • Basin-and-Range Province
  • Rio Grande Rift
  • Colorado Plateau
  • The Quaternary ice ages of North America

North American Craton stability

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I am rather confused as to what this sentence in the article refers to: "The stable core of the continent is the North American Craton". Obviously earthquakes occur throughout the craton and there are at least some active faults. Volcanoguy 21:20, 18 May 2013 (UTC)[reply]

The stability of the cratonic core of a continent does not mean there are no earthquakes in the vicinity. I am a little lost at the connection, as I do not see earthquakes mentioned in this sentence, and you say you are a geosciences professional, maybe I am missing something? Please elaborate, and we can clear this up for readers? Thank you. -166.137.191.22 (talk) 17:14, 19 May 2013 (UTC)[reply]
I never said I am a geosciences professional. All what I am trying to point out is whether or not it is really accurate to describe the craton as stable. Faults are reactivated along the Saint Lawrence rift system which is the location of the highly active Charlevoix Seismic Zone. And according to this the entire Reelfoot Rift has been tectonically active during the Quaternary. As a result, I doubt the North American Craton is really that stable. Maybe relatively stable but not completely stable. Volcanoguy 22:06, 19 May 2013 (UTC)[reply]
Yes, it is a relative thing. The craton is considered stable because it has not been involved in orogenies or successful rifting since the Proterozoic except along the margins. As P.B. King phrased it, "this part of the continent has been stable since the beginning of Cambrian time——a Central Stable Region (or more technically a craton) whose subsequent deformation has seldom been greater than gentle movements upward or downward, or mild warping and flexing." from "The Evolution of North America" Princeton University Press, 1971, p. 11.
The New Madrid Seismic Zone and the Saint Lawrence rift system are both failed rifts dating back to the Proterozoic or early Paleozoic and the historic seismic activity appear to be "adjustments" on old failed systems. Both are "relatively minor". Vsmith (talk) 23:14, 19 May 2013 (UTC)[reply]
Another thing I could bring up (not sure if it counts depending on how "stable" is used) is magmatic activity. It has occurred throughout the craton since the Proterozoic, especially in the Canadian Shield. For example, the Attawapiskat, Kirkland Lake, Churchill and Lac de Gras kimberlite fields. There is also the Labrador Sea-Baffin Bay rift system, which failed but still split Greenland from mainland North America during the Cretaceous period. Volcanoguy 07:36, 9 June 2013 (UTC)[reply]
I thought your page identified you as one. However, stable does not mean it does not have earthquakes, and the article does not say there are no earthquakes there. The reasons for seismic activities on cratons far from boundaries are often complex involving regional stress fields. Possibly we should elaborate is people equate stable with no earthquakes? I am not seeing that, but if it is common in non-geoscientists it should he cleared up. -166.137.191.22 (talk) 23:50, 19 May 2013 (UTC)[reply]
@Volcanoguy. I found this map http://citynoise.org/upload/14586.jpg - I can't comment to much because I'm still reading up on North America. But the map seems to outline the Craton pretty well. I couldn't find a depth dependent map so I'm not going to go into speculations what the within-craton earthquakes could mean. --Tobias1984 (talk) 17:31, 19 May 2013 (UTC)[reply]

Southern Cordillera

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The reference provided for this section was/is King, Philip (1969), The Tectonics of North America; however the url provided went to a different google books search about Long Island Hydrology. I've corrected that. However the 1969 ref is a bit dated and doesn't fully support the text. P.B. King was a great geologist, but his roots were in pre plate tectonic geology and some of the terminology is outdated - specifically here miogeosyncline a part of the old geosyncline theory of tectonics. I've change that to miogeocline as the current replacement, but obviously that goes beyond the reference. Will need additional modern refs to support. Vsmith (talk) 02:30, 27 May 2013 (UTC)[reply]

Yes, we should not be using and citing.1969 tectonics texts foe this article. -198.228.217.154 (talk) 09:15, 28 May 2013 (UTC)[reply]

Greenland

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The lede currently states:

The parts of the North American Plate that are not occupied by North American countries are usually not discussed as part of the regional geology. The regions that are not geographically North American but reside on the North American Plate include Siberia (see the Geology of Russia),[2] Greenland, Iceland and Bermuda.

Since when is Greenland not geographically part of North America? If it is not North America, then what continent does it belong to? The article's own diagram of the North American craton contradicts the claim that they are not discussed together. Sounds like cultural bias to me, geology doesn't stop at the line where the population stop speaking English. The Geology of North America: an overview covers Greenland in detail and mentions it on 69 different pages. Geologists and ideas: a history of North American geology has a whole chapter on East Greenland and mentions "Greenland" on 34 separate pages. SpinningSpark 13:27, 27 May 2013 (UTC)[reply]

Hi Spinningspark! Great to see that more people are interested in this topic. You're probably right about including Greenland. It is not important anymore now, but the original idea was to do Greenland separately because the map doesn't show it and because it was investigated more by European geologic surveys. If you have time to write a section and link it to the main Geology of Greenland article that would be great. --Tobias1984 (talk) 14:45, 27 May 2013 (UTC)[reply]
I am not intending to contribute anything significant to this article, I came to it by way of a DYK review. It is completely backwards to write an article to suite a map. If the map is not suitable for the article then find a better map (or use something else as the lede image), don't contort the article to fit an unsuitable map. If your comment about geological surveys is intended to mean that the US Geological Survey does not cover Greenland, then that is not really relevant. The title of this article is not "Geology of the United States" or "Geology of Continental North America". European sources should be perfectly acceptable. SpinningSpark 15:44, 27 May 2013 (UTC)[reply]
I think everybody involved knows that we shouldn't let a map or a survey jurisdiction decide on what should be the content of the article. I was just trying to do a (poorly worded) explanation of why Greenland is still missing. The article was created following the discussion that Geology of the United States should be deleted. Sections got pushed around a lot and at first there was some discussion on where to draw the outlines of the article (e.g. tectonic plate of North America vs. geographic definition of North America). It anyway doesn't matter now because most of it got sorted out by AlClimbs and at some point a section about Greenland will be added to the article. --Tobias1984 (talk) 16:19, 27 May 2013 (UTC)[reply]
The article contains dozens of major geological errors. Editors have agreed that it requires a major overhaul beginning with an outline based on DNAG. Greenland is a major part of North American geology. I do not see any intention to omit Greenland, although it may have been the case to focus on the provinces map. This is why the article should not be on the main page right now, this is only one of the major omissions/comissions, for whatever reason. -198.228.216.164 (talk) 17:09, 27 May 2013 (UTC)[reply]

American Cordillera

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The American Cordillera is the entire belt of mountains along the west coast of both continents. This articles remakes it as the belt along North America. -198.228.217.154 (talk) 09:25, 28 May 2013 (UTC)[reply]

Further reading

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Further reading contains sources that are too old, only older sources, and unavailable foreign language sources. The article is bad enough without misdirecting the reader to nothing useful. This section should be removed for now, and a new list of further reading can be added when the article is worth reading. A better article now is more important, but not leading the reader to older, too old, and unavailable sources in the meantime. -198.228.217.150 (talk) 09:30, 28 May 2013 (UTC)[reply]

We already discussed this. The sources are a little old, but they are still standard reading material (Northing much has changed about the mayor subdivisions in the newer literature). Instead of flooding the talk page you could use your time more wisely and improve the article. It's a Wiki: You do it, somebody does it, or nobody does it. --Tobias1984 (talk) 09:39, 28 May 2013 (UTC)[reply]
Please cite your source that indicates they are standard reading material, starting with the Clark and Eisbacher. Article requires gutting, too many major points wrong. One can rewrite an article requiring corrections, but should remove articles with major omissions and commissions. 198.228.217.174 (talk) 09:55, 28 May 2013 (UTC)[reply]
I looked up all the books on a citations database before adding them. They are all repeatedly cited up to 2013. They are even included in some lecture notes I found and Eisbacher recommends Clark, King, and Bally (he had access to the unpublished manuscripts at that time I guess). How much more coherent can it get? If you think the article is bad you can always nominate it for deletion ;). --Tobias1984 (talk) 10:05, 28 May 2013 (UTC)[reply]
What citations database? What lecture notes? And if Eisbacher is recommending unpublished versions, his rexommendation does not count. We use published sources in further reading. -198.228.217.174 (talk) 10:16, 28 May 2013 (UTC)[reply]
Try it yourself. All citation databases work with roughly the same data. Eisbacher's recommendation is published. Having access to "soon to be published" manuscripts for review, is standard practice in science. Either way it is published now and constantly cited. You would know most of these things if you had the knowledge you claim to have. --Tobias1984 (talk) 11:04, 28 May 2013 (UTC)[reply]
I have. I don't get any of these sources coming up in the first few dozen items returned in Geo Ref, scholar, WorldCat, my academic library, So, since you do, cite your sources or remove your original research. -198.228.217.150 (talk) 11:38, 28 May 2013 (UTC)[reply]

Stable platform

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This section is poorly developed and repetitive. The stable platform is the Interior Plains, part of which is the Great Plains. There was not just one inland sea, and it was not covered by it the entire time, and it should not imply that it was. This section needs a rewrite. -68.107.136.227 (talk) 22:28, 28 May 2013 (UTC)[reply]

Midcontinent rift system

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This, "and then crustal movement reversed and a range formed, which eroded, forming basins on either side of a horst" does not make sense. Crustal movement reversed? You mean normal faults were reactivated as reverse faults? The eroding range surely did not form the basins on either side of a horst? I thought it was a central rift? -68.107.136.227 (talk) 22:33, 28 May 2013 (UTC)[reply]

Those statements are based on the following source. The explanation of tectonic movement comes from the third paragraph, where crustal movement is described as reversing. It is possible that this is a simplification, but it is the terminology that the source uses. The graphic on that page also clearly shows a horst with basins on either side, and also repeatedly describes a horst with flanking basins in the fourth and fifth paragraphs. The current source is by a adjunct assistant professor of geophysics at the University of Iowa, publishing on the university's website, something that I consider a reliable source. If something is incorrect there, a more reliable source or multiple sources would need to be presented and the correct details fleshed out.--Al Climbs (talk) 09:43, 2 June 2013 (UTC)[reply]
There is no third paragraph on the page you link to, and the page you do link to says basically what I am saying, not what the article says. I do not see any graphic that shows a horst with basins on either side. You seem to be saying that the source says there is a central horst, not a central rift, and the sentence in the article does not match the single source you give, "One billion years ago, the Midcontinent Rift System began to extend along a 2,000 kilometres (1,200 mi) path,[11] across both the Canadian Shield and the Stable Platform. The rift, however, failed, and afterwards crustal movement reversed. A range formed then eroded, forming basins on either side of a horst. These rocks have been buried beneath sediment in many areas, but are exposed in some areas, especially around Lake Superior.[12]" If the rift failed and crustal movement reversed, this means tectonically what I suggest above, that normal faults were reactivated as reverse faults, common enough. However, you have added a step saying that the central basin has been uplifted as a horst, except that horsts are structures created by normal faulting. I'm just not really sure what you are sauing; but, if you move from reverse crustal movement, a compressional regime, into a range forming basins on either side of a horst due to erosion, you have now moved back into an extensional regime (horsts). The geophysics page you link to does not say on it, what you have written in the article. -208.46.240.4 (talk) 18:56, 4 June 2013 (UTC)[reply]
The 3rd paragraph of the UIowa ref does indeed discuss "uplift" and "horst" as does the Basement Tectonics 10 book (ISBN 978-0792334293) mentioned on the Did you know template page. Obviously the geologic history of the rift is complex, and thus rather difficult to address adequately in a brief section. Indeed the "horst" terminology and "mountain range" of the UIowa source does seem a bit at odds with my expectations. The Basement Tectonics 10 book doesn't say "mountain range" (at least not in the google books exerpt I can access) and would be a preferred ref if someone has access to it. Vsmith (talk) 21:17, 4 June 2013 (UTC)[reply]

Also, shouldn't Keweenaw Fault should somehow be gotten into this section? I don't know much about this area of the continent, but it's what I would read if I did. -68.107.136.227 (talk) 22:35, 28 May 2013 (UTC)[reply]

The Keweenaw fault appears to be a much smaller fault that is described as related to the mid-continent rift.[1] I cannot tell at this time if it deserves a mention.--Al Climbs (talk) 09:43, 2 June 2013 (UTC) corrected.--Al Climbs (talk) 10:06, 2 June 2013 (UTC)[reply]

The Keweenaw fault is a major structure, not all structures are importance based on size alone. Even the sources you cite place major emphasis on it, so this should be your cue as to its importance. -208.46.240.4 (talk) 18:57, 4 June 2013 (UTC)[reply]

The Keweenaw Fault is a major fault along the SE margin of the rift in Michigan's UP. Figure 38 here illustrates the structure with two reverse faults forming an uplifted central block or "horst". The info and images are in The geologic story of Isle Royale National Park, USGS Bulletin 1309 (1975). Vsmith (talk) 21:34, 4 June 2013 (UTC)[reply]

References

  1. ^ "VIRTUAL FIELD TRIP TO THE KEWEENAW PENINSULA, MICHIGAN - STRUCTURE". Mineralogical Society of America. Retrieved 2 June 2013.

New introduction

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I was thinking a bit how we could alleviate one of the big problems of this article and the one that has haunted the talk page of Continent (and has created a 4-archives-long argument whether Greenland is and island, Australia a continent and how many continents there are in general). We just have to embrace the fuzziness of this geographic term and do our best to create understanding of why certain boundaries are drawn. The way landmasses are sorted into continents is a product of many different fields of thought, but to a large part a product of pettiness, patriotism, and ignorance of what lies beyond a small stretch of water. Just like the definition of life, there is no single geographic or geologic argument that can define a continent. The outcome of a scientific division would always clash with "but I learned in school that ..."-kind of arguments. Even the division by lithospheric plates is nonsensical, because it relies on recent motions and just raises the follow-up question what can be considered enough relative motion between 2 pieces of continental crust, in order to separate them. We also have to explain that continuation of geologic units is usually ignored. Units continue into Greenland, therefore Greenland is a part of North America. But: Cordillera continues into South America, therefore not a part of North America. You see where this is going ;)

My idea is to aim for maximum descriptiveness for the introduction-section. Explaining what North America is in the minds of most people, why that doesn't make any geologic sense (nor any geographic sense), and then explain that we are going to use the term anyway, because it is more-or-less a good order-of-magnitude to view geologic processes. I know this will again warp the minds of a large part of the non-scientific community, but there is just no alternative I can think of for an encyclopedia. We can't just write "The North American continent is a big continent ..." believing that any words between those two quotations have any intrinsic meaning. I thought of something like this (ideally edited over a couple of times):

The geographic term North America refers to a accumulation of continental crust that occupies large parts of the North American Plate. Not all of the continental crust on the North American Plate belongs to the North American continent, as it is commonly understood. The crust in the west of the Bering Sea for example is considered a part of Eurasian or Asian, although it is only a flooded continental shelf and the two continents were connected during the Pleistocene glaciation. Greenland on the other hand is usually viewed as a subcontinent of the North American continent, partially separated by Baffin Bay and the Labrador Sea that are floored by a failed rift (ISBN 978-0-309-02928-5, page 47). The western half of Iceland, although lying on the North American continent is neither politically nor geologically considered a part of North America. In the south North America connects across Central America with South America, each occupying their own lithospheric plate. Many geologic units (e.g. the American Cordillera) formed through similar geologic processes and the division is scientifically arbitrary.

  The North American Plate, shown in brown
The western half of Iceland lies on the North American Plate but is not considered a part of the North American continent.

For citations I thought of going with "Myth of Continents: A Critique of Metageography , ISBN-13: 978-0520207431", because it explains the reasons for how the subdivisions used to be drawn and how they are drawn today. --Tobias1984 (talk) 10:59, 3 June 2013 (UTC)[reply]

Greenland again

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I've removed the following detail about Greenland from the lead image:

Greenland is usually seen as a part of the North American continent although they are separated by a narrow failed rift, which forms the basin of the Labrador Sea and Baffin Bay.

The removed bit should be added to a relevant section as it seems too detailed for the lead. Vsmith (talk) 21:29, 5 June 2013 (UTC)[reply]

Appears the ref <ref name="Quisling 1980">{{cite book|last=Quisling|first=Ronald G.|title=Continental tectonics|year=1980|publisher=National Academy of Sciences|location=Washington, D. C|isbn=978-0-309-02928-5}}</ref> was in support of the Greenland content and should go with it. See: this book search. Vsmith (talk) 22:39, 5 June 2013 (UTC)[reply]

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