Talk:List of possible impact structures on Earth
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editis Houston in a 100Myo crater? Has anyone noticed that there is a diameter-50-mile ring ridge around Houston? If the ring was a clock face on a north-up map, downtown houston would be at the tip of the hour hand at three o'clock. 2605:6000:3D13:1300:40F5:25AB:8C18:F853 (talk) 02:50, 29 August 2017 (UTC)
Unconfirmed Impact Crater in Oregon (Not Caldera)
editWith center in Parker Meadow 43°13'54.9"N 121°29'58.9"W a great circular structure with 23 miles (some like 37.5 kilometers) of diameter is very noticeable on any aerial or satelital image at northeast of the Crater Lake National Park, without proof of how this structure was created we could see clearely how erosion and other climatic circumstances try to erase the particular form but perfectly looks as a old crater.
Agree it does look pretty crater-y at least on satellite photos. One thing to keep in mind though is that area has a lot, and I mean a lot, of Volcanic craters. Literally on the outer rim of the structure in question are Big Hole and Hole In The Ground, a pair of quite large volcanic Maars 2 and 1.2 km in diameter respectively that practically scream "astrobleme" but most definitely aren't. Within 2 diameters in either direction we have crater lake, the Newberry Volcano with it's two crater lakes. Further still, the central area is still elevated above the surrounding terrain. That means that if there is indeed a crater there the impactor would've had to flatten out some mountainous terrain rather than making a hole in flat terrain. — Preceding unsigned comment added by 71.237.249.230 (talk) 13:36, 8 February 2021 (UTC)
- This is only a list of suspected impact craters that have recognized by reliable and verifiable sources and it does not include original research. If you have questions about this feature, you can contact the Oregon Department of Geology and Mineral Industries. They might be able to reccommend where you can find additional information about this feature. Paul H. (talk) 15:56, 8 February 2021 (UTC)
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Need to add major Greenland crater
editHiawatha Crater (name?) - 19km. [1] Fig (talk) 21:21, 14 November 2018 (UTC)
The reason I changed the age of Hiawatha crater to "less than 1,985 million years" in the table is because according to the authoritative reference Kjaer et al. (2018)[1] "We can confidently assume that the structure is younger than the 1.985 to 1.740 Ga old Paleoproterozoic bedrock that outcrops in the immediately adjacent foreland." This is an actual age constraint and is not tentative or merely inferred from indirect evidence. There is no mention of 2.58 Ma in the paper. KosmicMuffin (talk) 17:43, 20 November 2018 (UTC)
References
- ^ Kjær, Kurt H.; et al. "A large impact crater beneath Hiawatha Glacier in northwest Greenland". doi:10.1126/sciadv.aar8173. Retrieved November 20, 2018.
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Rename and revamp this page?
editThere are numerous problems with this page, which appears to have been hastily assembled. The title "List of unconfirmed impact craters on Earth" is already a problem. First, it implies that it is a list of craters when many of the listed geographic features are not craters at all by any definition. Second it suggests that listed features are impact craters that just haven't been formally designated yet. Third, there are lists of other things on the page besides unconfirmed impact craters (undiscovered but inferred, formerly unconfirmed, and mistaken identity). I suggest the following. Rename the page something like "List of misidentified, contested, or unconfirmed impact features on Earth". Consolidate everything into a single list and add a column stating the status of the scientific consensus, with citations. KosmicMuffin (talk) 16:28, 18 January 2019 (UTC)
- sorry, I didn't know that I reverted your edit. I was looking at a bunch of article edit histories from my watch list, and some how accidentally rolled back the wrong article. That was weird. Now I'm wondering which article I meant to revert, uggg. • Sbmeirow • Talk • 19:23, 22 January 2019 (UTC)
- It has been 4 weeks since I proposed changing the title and reorganizing this list, with no feedback from anyone. Unless there is an objection, I intend to change the title by moving the page to "List of misidentified or unconfirmed impact features on Earth". The tables need a lot of work and I would like to make sure that all information is referenced to a reliable source or else removed. For example there is no citation to location or diameter data for most of these surface features. If I cannot find a source that confirms this info, I will delete the data from that box. KosmicMuffin (talk) 15:51, 14 February 2019 (UTC)
- Go easy on rabid deletions KosmicMuffin - people made efforts to stick impacts on this list. Also, rather than marking items {cn}, you might think about rooting up their references. If you move the page to a new title please also include a redirect from the old one. - 173.20.144.157 (talk) 13:18, 30 March 2019 (UTC)
- Thanks for comment. I'm not sure where the unreferenced info came from that was put into this table. Without citations I don't know where to begin other than just doing my own research by going to the library or searching the internet, but doesn't that defeat the purpose of Wikipedia? Many of the table entries are just statements that cannot be verified. I suspect that they are independent research. I will add a tag for now. I will pick through them one at a time but I would encourage others to help (which I understood was the purpose of the tags I put in). KosmicMuffin (talk) 15:45, 1 April 2019 (UTC)
It seems to me that the "formerly unconfirmed" section is out of place and redundant. Out of place because this page is supposed to be a list of *unconfirmed* craters and these are *confirmed* craters. Redundant because they are already listed on the confirmed impact crater page. If there are no objections I think this section should be deleted.KosmicMuffin (talk) 06:35, 16 February 2019 (UTC)
- @KosmicMuffin:, I didn't see the comments you posted here, just the wall of "citation needed" tags that was ridiculously spamming the page unnecessarily, and still is. Not every entry in a table needs to be referenced, especially not location. What usually happens in table lists like this is a separate column for "notes". There proper references can be added and individual entries can get a tag "citation needed" or "not in citation given". The solution for that is look for other refs or place tags. Not spam the whole page.
- It wasn't intended as spam, just as notifications that citations are needed. Perhaps they could have been put at the top of the each column with a note that each entry in the column needs a reference. I will do it that way next time, for less visual impact. Nevertheless, these entries need to be sourced if they are based on someone's research. If they are based on original research, I'm not sure they are valid.KosmicMuffin (talk) 18:58, 1 April 2019 (UTC)
- " I suggest the following. Rename the page something like "List of misidentified, contested, or unconfirmed impact features on Earth".
- An awkwardly long and improper title. What is "misidentified"? "Contested"? Everything can be contested. The terms "confirmed" and "unconfirmed" in this context refer to the status given by the Earth Impact Database, as explained in the lede, but other groups of researchers, like Impact Field Studies Group (IFSG) and/or Expert Database on Earth Impact Structures (EDEIS) propose these features as possible, probable, likely or speculative impact craters, as explained in the lede. This is not a list where Joe Plummer finds a circular feature on Google Earth and puts an entry in. The EID uses a strict set of criteria, understandably, but there are many features that are either inaccessible, inconclusive, in volcanic or salt tectonic areas (think Silverpit) or otherwise not meeting the criteria the EID sets out. That doesn't mean they are not impact craters, it just means they do not have enough confidence level to designate these features as such.
- OK, I think we can omit "contested". But I think that "misidentified" needs to be there as long as there is a section on this page called "mistaken identity" which I think already answers your question "what is 'misidentified'" like this: "Some geological processes can result in circular or near-circular features that may be mistaken for impact craters." KosmicMuffin (talk) 18:58, 1 April 2019 (UTC)
- "Consolidate everything into a single list and add a column stating the status of the scientific consensus, with citations." Everything is in a single list, and adding that column is a good idea. The Russian Academy of Sciences, not some nobody who just makes bold claims, has compiled an exhaustive list with possible ages, links to sources and locations (that you requested needed to be "cited") and assign 5 confidence levels: proven (=our "confirmed"), probable, potential, questionable and discredited (which don't appear in our list afaik and if they do, should be removed). I have worked on quite some of these "unconfirmed" craters and started articles where this list is referenced, see for instance Cerro do Jarau crater. The entry in the infobox for "Confidence" gives "Probable", and is referencing the list. This is not a black-and-white matter as the confidence level designation proves, so a comments like "First, it implies that it is a list of craters"; a circular depression of any kind is a crater. A bomb crater is a crater, and even an impact one, but not by an extraterrestrial body obviously. A volcanic crater is a crater, but again not formed by a bolide. "it suggests that listed features are impact craters that just haven't been formally designated yet"; in some cases yes, this is the case, and the EID is growing, so previously "unconfirmed" (appearing on this list) impact craters may move to the "confirmed" (=by EID) list, because new research meets their criteria. As you can see, the Russian Academy of Sciences uses the title "The Complete Catalog of the Earth's Impact structures", which also might imply they are all "impact structures", but if you read a bit more than just the headline, you get information on what their confidence level is.
- In my view it is better to refer to them "unconfirmed impact structures" than "unconfirmed impact craters". Many impact structures (e.g. Santa Fe) are just roots of what inferred to have been a crater before it eroded. But it is not a crater today and should not be called a crater. Likewise, Rio Quarto is not a crater at all, but an unusual geological formation that some researchers argue is associated with an impact event. For that reason the word "crater" in the title of this page is misleading.KosmicMuffin (talk) 18:58, 1 April 2019 (UTC)
- The problem with lists in general is that referencing them may be double work, as the article itself already contains the references needed, again see Cerro do Jarau. Your proposal "add a column for confidence", like the Russian list has, is good, but if you want to see that, then work on that, instead of spamming a list with "citation needed" tags that do not help in improving the list. Tisquesusa (talk) 14:28, 30 March 2019 (UTC)
- I will work on that. The reason I added what you call spam is to encourage others to work on it as well. I understand that Wikipedia is a team effort. KosmicMuffin (talk) 18:58, 1 April 2019 (UTC)
- Adding: even impact craters that are "confirmed" by the EID can be "contested" by other researchers, see for instance Río Cuarto craters, referenced with online accessible sources. Tisquesusa (talk) 14:57, 30 March 2019 (UTC)
Work done
edit- renamed list to "List of possible impact structures on Earth", rationale; "impact structures" is the wording used by the Russian Academy of Sciences (Mikheeva) and is indeed more neutral than "craters", although specific entries may be called "crater" (that does not depend on our decision, but what the particular sources say about those craters/"craters"; Wikipedia reflects what the sources say), "possible" includes probable (high confidence), potential (medium) or questionable (low) and is also the name of the category we use.
- organized alphabetically, which was not the case in many instances
- added links to individual crater pages of the Mikheeva list (that is much more complete than ours)
- added confidence level, as indicated in that database
- added approximately 20-25 extra references, mostly for structures that already had references, about 5-10 of them did not
- images that were placed outside of the table now appear at the correct location for each crater
- result of this work that took me 4.5 hours, not much more than adding "cn" temps:
- 17 craters are now "confirmed" (EID term) or "proven" (used by other databases) since they were added to this list - visible as confidence 0, so need to be moved to the appropriate lists per continent
- 2 structures are now "discredited" (Mikheeva 4), so need to be removed from the list but not until the articles are well described that they were discredited and on which basis
- 6 structures need citations for their confidence level (not to be found in Mikheeva's extensive database), 3 of those also do not have other references, as can be seen in the column, so a total of 9 citations are needed.
- this (2.2%, and counting the max. 10 extra for previously unreferenced entries; 4.6%) heavily contrasts with the whopping 410 "citation needed temps" @KosmicMuffin: you added back in February, don't you consider that at least a bit overkill and at most spam? Tisquesusa (talk) 02:41, 3 April 2019 (UTC)
- It should be noted that Impact craters and impact structures are two different types of physical structures, which people, including various Earth scientists, use interchangably. As stated in the Wikipedia article and any scientific glossary, "An impact crater is an approximately circular depression in the surface of a planet, moon, or other solid body in the Solar System or elsewhere, formed by the hypervelocity impact of a smaller body." As typified by American Geological Institute's Glossary of Geology, an impact structure is a generally circular or craterlike geologic structure of deformed bedrock or sediment produced by impact on a planetary surface whatever the stage of erosion of the structure. Basically, an impact crater is the surface expression of an impact structure, which in many cases has been destroyed by erosion. That distinction should be made in the name of an impact structure and another rational for renaming this list to "List of possible impact structures on Earth" because it is more emcopassing of these features.
- It is worth keeping "discredited" impact structures on this list as long as they are labeled as such. They should be kept as this list is where people will look information about them. It also will keep people from adding their favorite discredited impact structure, e.g. Richat Structure, thinking that it has been overlooked.
- Another resoucre is David Rajmon's Global Impact Crater GIS Project GIS Open File, American Association of Petroleum Geologists Datapages. Paul H. (talk) 21:24, 7 April 2019 (UTC)
>>Winton crustal anomaly
editI do not believe that the possible impact structure named by one article as the Winton crustal anomaly is the same as the site named by Tisquesusa as the Diamantina River craters. The sheer size of the Winton site surely puts the lie to that. The three tiny craters shown in the reference included with that modification each barely measure 100 m across, but the Winton crustal anomaly's diameter is more like 130 km. The webpage used as a reference (here) also does not give coördinates, making it impossible to confirm whether those that are included with the entry indeed point to these little holes. Now, I know, because I wrote the Winton crustal anomaly article, that the coördinates used there (which have been copied here) are only designed to point roughly at the centre of that cane-shaped bit of the upper Diamantina, and are hardly pinpoint-accurate, using a fineness only down to a tenth of a degree. Tisquesusa (or somebody else) would need to find a position for those three craters in the now removed reference. I suspect, though, that those craters would turn out to be another entry.
Please also note the little inline advisory in the "Unnamed impact" entry: "Winton crustal anomaly" is simply an unofficial name that I have given it, because it needed one to have an article about it. That article may be moved if Geoscience Australia comes up with an official name.
But thus far, it doesn't seem to have. Kelisi (talk) 01:37, 7 April 2019 (UTC)
- No need to worry about. According the literature,"Diamantina River ring feature" is currrently the proper name of the "Winton crustal anomaly." For confirmation of this go see:
- Glikson, A., Korsch, R.J. and Milligan, P., 2016. The Diamantina River ring feature, Winton region, western Queensland. Australian Journal of Earth Sciences, 63(5), pp.653-663.
- Glikson, A.Y. and Pirajno, F., 2018. Ring and Dome Features, Possible and Probable Impact Structures. In Asteroids Impacts, Crustal Evolution and Related Mineral Systems with Special Reference to Australia (pp. 123-156). Springer, Cham.
- Glikson, A., 2018. Structure and origin of Australian ring and dome features with reference to the search for asteroid impact events. Tectonophysics, 722, pp.175-196.
- Also, as seen in the above papers, "ring feature" is a valid geological term for the Diamantina River ring feature as its origin is unknown at this time and it is what geologists would describe as a "ring feature." I have not been able to find anything about the Diamantina River craters. I will keep looking. Finally, ring features / structures are quite common and still very enigmatic as seen in
- Saul, J.M., 1978. Circular structures of large scale and great age on the Earth's surface. Nature, 271(5643), p.345. Paul H. (talk) 22:15, 7 April 2019 (UTC)
Serious errors in crater diameter section
editI looked up some of the big, young craters and there are some truly horrendous errors in size. The discredited one near Tunguska claims 50 km in diameter on this page (which is absurd because a 50 km crater would be 1/10th chicxulub energy or 1/1000th Shiva, I think that would probably completely depopulate central Siberia at minimum). The lake is not 50 km in diameter. It's 50 meters in depth.
Similarly, the 5000 B.C. Zerelia structures in Greece claim they are 20 and 10 km in diameter. They are plainly visible dual crater lakes on satellite imagery and the visible portion is more like 0.3 and 0.2 km respectively. 20 km impact would make the thing a new bay to the Aegean and probably give neolithic mediterraneans a new deluge myth from the trauma.
There are more. Probably at least half a dozen errors by a factor of more than 10. Someone with more time and better understanding of how to edit please do a thorough sweep of these and check sizes with sources and if possible satellite photos. Merewether also may not be as big as it says but it's somewhat difficult to know if the article is talking about a small (like, hundred ish meters) circular lake or something else. — Preceding unsigned comment added by 71.237.249.230 (talk) 12:46, 8 February 2021 (UTC)
Important craters missing
editE.g., the Nördlinger Ries in Germany is missing in the list. (It is listed at the end of the page in the categories section.) As it is above 20 km in diameter, well researched, and since this crater was even historically important for the development of the impact crater theory as far as I remember, that one is very bad to miss out on the list, and makes me wonder how many else are missing... — Preceding unsigned comment added by 2.207.106.136 (talk) 09:53, 3 June 2021 (UTC)
My (perhaps incorrect) understanding is that confirmed craters do not belong on this page. If that is the case, then the certainty "0" craters (which would include Nördlinger Ries, were it here) should be removed. 2600:1700:FD0:E9E0:68A1:BA2F:2F81:B2D5 (talk) 13:47, 23 August 2021 (UTC)
- But on the other hand, the El Bahr Crater is not on the list either, so the list is not up to date. It may not be an impact crater, but the current hypothesis is that it might be. I would call it a category 2. 62.44.135.225 (talk) 06:19, 28 August 2021 (UTC)
What qualifies Anna Mikheeva's "The Complete Catalog of the Earth's Impact structures" (ICM&MG SB RAS) as a reliable source?
editDoes anyone know what level of expertise that Anna Mikheeva has in the study of extraterrestrial impacts? Why is "The Complete Catalog of the Earth's Impact structures" (ICM&MG SB RAS) cited in this article as if it a reliable secondary source unlike similar seemingly self-published lists of impact craters?
I ask, because in her list, there are some widely implausible "impact" structures given high probabilities by her of being impact structures for which enough is currently known about their geology to completely discredit them as being valid impact structures. One example is the "Kilimanjaro (Tanzanian nuclear, Vostochno-Africanzkaya-D=800km, Lake Victoria, Lac Victoria, Victoria Njansa-D=250km) * Africa., which two perceived features are given a rating of 1 and judged to be "probable" impact structures. This and other examples argues for this being a personal compilation of any feature that at one time or the other have been proposed an impact structure without much though as to the the quality of the evidence supporting the claim. A map of such features is Yandex map of impact structures. From what I can find, this list is a blatantly unreliable, self-published source that should not be used / mentioned in Wikipedia. Paul H. (talk) 04:20, 4 January 2022 (UTC)
- Anna Mikheeva's page at Research Gate is https://www.researchgate.net/profile/Anna-Mikheeva . She seems to be a Russian academic with many years of experience of academic research/publication in geology and geophysics (I found some of her older publications/work at some websites/journals dating back about 15 years). In addition to her impact structure database, she has also created an earthquake database and a natural disasters database. The fact that she has created three such databases makes me doubt her level of expertise because I doubt that she can be authoritative on all three subjects. I get the impression that these databases are her own well-meaning attempts (while specialising in computational mathematics aspects of geoscience) at starting something that could eventually become authoritative if they were embraced by other (expert) contributors. I think it is probably best to regard her impact database as unreliable. GeoWriter (talk) 17:47, 16 January 2023 (UTC)
Crater
edithttps://en.m.wikipedia.org/wiki/Craton VerifyTruth927 (talk) 05:47, 8 June 2022 (UTC)
Nadir impact crater
editI am not sure how to edit hyperlinks on here, but the link for Nadir redirects to the wrong page, not the one about the crater 2003:CC:272B:9D00:61AF:596D:91E3:842F (talk) 22:40, 2 October 2022 (UTC)
List inclusion criteria and possible unreliable sources
editList articles (like this one) should have clear inclusion criteria. The lede of this article lists three databases that contain possible impact structures:
- Impact Field Studies Group (IFSG) [2]
- Expert Database on Earth Impact Structures (EDEIS) [3]
- Earth Impact Database (EID) [4]
Do editors believe that these databases are reliable and authoritative? If so, then we can include a structure that occurs in at least 2 of these three databases. That will fulfill the notability criteria. Further references for each included structure could be useful, but we wouldn't have to attempt to validate the reliability of hundreds of references to support inclusion.
What do other editors think? pinging relevant editors (Doug Weller—Paul H.—Hemiauchenia—Licks-rocks) — hike395 (talk) 14:07, 16 January 2023 (UTC)
- I see from this previous discussion that there is doubt about the reliability of EDEIS. We could drop it and simply rely on the intersection between Rajmon's list and the EID list. Is EDEIS junk, or could it help confirm an entry in IFSG and EID? — hike395 (talk) 14:19, 16 January 2023 (UTC)
- No comment on EDEIS but the principal seems right. Doug Weller talk 14:25, 16 January 2023 (UTC)
- Another databass I've found (if we want to drop EDEIS) is Impact Earth [5]. And, fwiw, there's a published paper about EDEIS: [6], although not in any journal that I recognize. — hike395 (talk) 16:46, 16 January 2023 (UTC)
- IMO, this list article contains pathological science. To quote the article itself, "that some individuals have associated with impact events, but for which there is currently no confirming scientific evidence in the peer-reviewed literature". This article clearly violates WP:RS and needs to either be cleaned up or deleted. — hike395 (talk) 17:19, 16 January 2023 (UTC)
- From Paul H.'s and GeoWriter's comments, above, it seems like EDEIS just isn't reliable enough to use. I'm going to make another proposal, below.
- I agree with dropping EDEIS as an unreliable. Paul H. (talk) 01:01, 17 January 2023 (UTC)
- No comment on EDEIS but the principal seems right. Doug Weller talk 14:25, 16 January 2023 (UTC)
The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
New proposal
editI don't see why Wikipedia needs both a List of impact craters on Earth and a List of possible impact structures on Earth. To me, this seems to be a WP:REDUNDANTFORK. How about if we create a merged List of impact structures on Earth that have solid support in secondary sources? Namely, any such structure should be listed in at least two of the following databases:
- Earth Impact Database (EID) [7]
- Impact Field Studies Group (IFSG) [8]
- Impact Earth [9]
We can keep the current sub-lists in List of impact craters and append a new sub-list which contains a trimmed-down version of List of possible impact structures on Earth that passes the secondary source filter. — hike395 (talk) 21:47, 16 January 2023 (UTC)
- Thanks for tagging me! I think this seems like a decent plan. Is it a good idea to only include entries from the list of possible impact structures if they are E independently of their existence in these databases? This to further cull their numbers and avoid situations where we have to go back and retroactively remove large numbers of entries every so often. Licks-rocks (talk) 11:47, 17 January 2023 (UTC)
- Is there a specific procedure and criteria for challenging the inclusion and subsequent removal of a feature / possible impact structure from the "List of possible impact structures on Earth"? For example, does a person need propose a cadidate deletion on this talk page and wait a reasonable period of time to see if anybody objects before doing it? Paul H. (talk) 04:29, 29 January 2023 (UTC)
- I would think the usual procedure applies --- anyone could remove an inclusion immediately, and if the deletion is challenged, then take it to Talk and attempt to come to consensus. — hike395 (talk) 10:11, 29 January 2023 (UTC)
- Oppose There should be a clean list that solely includes confirmed craters listed in the EID that could potentially be made into a featured list someday. The "proposed impact crater" criterion is too vague for it to ever be rigorous, and thus it should be kept separate. Hemiauchenia (talk) 21:52, 23 February 2023 (UTC)
- Oppose I agree with Hemiauchenia that there should remain two lists. First, would be a list "that solely includes confirmed craters listed in the EID." Finally, there would be a list of proposed impact craters based reliable sources, notability, and secondary and tertiary sources reviewing primary sources. The criteria for the latter list will likely be always too lax and ambiguous to be rigerous. Combining these two lists will just confuse people as the extent that craters on either list have been vetted and reviewed for the quality of the research supporting their idenification as crates. Paul H. (talk) 03:31, 24 February 2023 (UTC)