Talk:Vredefort impact structure

Size

The size of the crater given in this article is somewhat confusing. It is stated that "the original size of the impact structure could have been 250 km in diameter, or possibly larger" and that "The crater has a diameter of roughly 300 km". While it's possible that both these are true, if that's the case an explanation of how the crater grew by 50km in diameter would be good. If only one of them's true, the other is either redundent or incorrect, though as I'm only really browsing through this post I don't really have the knowledge or the motivation to correct it. --143.167.228.12 17:45, 30 June 2006 (UTC)

Even worse, the phrasing "The bolide that hit Vredefort is (...) estimated at over 10 km (6 miles) wide, although it is believed by many that the original size of the impact structure could have been 250 km in diameter" seems to confuse the size of the bolide and the size of the resulting crater. (not to mention the weasel words) ComaVN 09:27, 20 November 2006 (UTC)

?? Statement has been removed., ComaVN--Alhizar (talk) 23:17, 3 August 2008 (UTC)

Removed the word "although" from misleading the sentence and corrected figures for both Sudbury and Vredefort according to figures represented at the HartRAO site., 143.167.228.12--Alhizar (talk) 23:08, 3 August 2008 (UTC)

The colour satellite image in the article is upside down.

It should look like the black and white image that is correct —Preceding unsigned comment added by Brinkja (talk • contribs) 15:35, 6 March 2008 (UTC)

The initial claim "The asteroid that hit Vredefort is one of the largest to ever impact Earth" is a bit strong, considering (a) that we expect cratering to have been heavier in the early solar system, and (b) plate tectonics erases the crater record on Earth's surface. The qualification "at least since the Hadean" attempts to make the claim more accurate, but it is probably incorrect because it seems unlikely that we have a full crater record since the Hadean. —Preceding unsigned comment added by 76.2.226.198 (talk) 15:48, 29 August 2009 (UTC)

World Heritage Listing

I think more needs to be said about the world heritage listing. Normally a listing would be part of a greater national park or something, but this article does not mention this. Also would this crater make it the largest World Heritage listed property on Earth?203.94.54.14 (talk) 05:31, 10 December 2008 (UTC)

Add Crater Infobox?

Someone may want to apply crater template {{Infobox crater | crater_name = {{SUBST:PAGENAME}} | image_crater = | alt_crater = | caption_crater = | image_bathymetry = | alt_bathymetry = | caption_bathymetry = | location = | coords = {{coord|89|59|59|N|179|59|59|W|region:ZZ_type:waterbody|display =inline,title}} | type = | basin_countries = | length = | width = | area = | depth = | max-depth = | volume = | rim = | elevation = | cities = | reference = }}

Crater characteristics

--YakbutterT (talk) 23:34, 18 February 2010 (UTC)

Mineral deposits

The huge crater right on top and the same age as the world's biggest precious metal reserves begs the question of whether the two are related... If the impact asteroid was an M-type asteroid perhaps this might be expected? Fig (talk) 11:55, 18 November 2011 (UTC)

Size of the asteroid

How come "The asteroid is thought to have been approximately 5–10 km (3.1–6.2 mi) in diameter" if with the Sudbury Basin the "The basin formed as an impact from a bolide approximately 10–15 km (6.2–9.3 mi) in diameter" and with Chicxulub crater it is mentioned that "the impacting bolide that formed the crater was at least 10 km (6 mi) in diameter". How could a smaller bolide generate much bigger impact structure? It might be explained be the material of the bolide but this should then be explained in the article as well. Ivo (talk) 09:11, 7 April 2012 (UTC)

Age vs Sudbury Basin

The age is listed as ~2 billion years, and then two sentences later it says "this makes it approximately twice as old as the Sudbury basin crater at 1.89 billion years". Since when does 2 x 2 = 2? Is Vredefort four billion years old, or is not twice as old as Sudbury? Hamiltondaniel (talk) 15:41, 18 April 2012 (UTC)

Vredefort meteor impact not contemporaneous with laying down of mineral-rich Witwatersrand and Bushveld Supergroups

Probably as a result of the 2011 comment above, the article incorrectly claims that the meteor impact was contemporaneous with the laying down of the mineral-rich Witwatersrand and Bushveld rocks. In fact these rocks were laid down well before the meteor impact. But the impact crater distorted these layers of rocks bringing parts of them to the surface, while burying other parts of them deep beneath the surface. The incorrect paragraph has been been replaced with a more correct, and hopefully more informative paragraph. Oggmus (talk) 09:17, 8 February 2014 (UTC)

Life on Earth

Given the size of the crater I presume it had a significant 'impact' on the Earth's then ecosystem. So what was the effect on life on Earth, and subsequent evolution ? The Yeti (talk) 23:49, 6 October 2015 (UTC)

based on this

https://www.youtube.com/watch?v=qf12HRglPPQ

the impact is probably not known as life was only at the cyanobacteria stage - though probably dust cloud would have affected the solar radiation and thus life at the time. EdwardLane (talk) 18:11, 20 September 2024 (UTC)

Formation and Structure

The paragraph

"The crater's age is estimated to be 2.023 billion years (± 4 million years),[1] which places it in the Paleoproterozoic Era. It is the second-oldest known crater on Earth, a little less than 300 million years younger than the Suavjärvi crater in Russia. In comparison, it is about 10% older than the Sudbury Basin impact (at 1.849 billion years)."

compares the age of the Vredefort Crater with one crater by delta and with the other by percentage. It seems to me it would be clearer and more helpful to present both comparisons on the same basis; and (though I'm not a geologist) a percentage difference in age seems a less useful measure.

Any comments or thoughts from others, please?

108.171.128.180 (talk) 10:39, 8 January 2020 (UTC)

age vs. Yarrabubba-Suavjarvi

In the Introduction it is said that Vredefort is the second oldest impact structure after Yarrabubba; later on (in the Formation and structure section) it is said that it is the second oldest after Suavjarvi. Suavjarvi is reportedly older than Yarrabubba - thus the correct statement should be "Vredefort is third oldest impact structure after Suavjarvi and Yarrabubba". In any case, as it stands now the text is contradictory.

It is the second-oldest known crater on Earth

It is the second-oldest known crater on Earth, after Yarrabubba crater.
It is the second-oldest known crater on Earth, a little less than 300 million years younger than the Suavjärvi crater in Russia.

Jidanni (talk) 21:50, 18 November 2021 (UTC)

Incorrect cross section.

The schematic geologic cross section is way off. A crater of vredefort's size (300km) would have a peak ring, not a simple central uplift. Also, based on what we know from chicxulub, this crater would likely have a melt sheet contained within the peak ring.

The diagram portrayed here may be a snapshot of the "rebound" phase of complex crater formation, which only lasts for a few minutes. It should be taken down, as it is misleading, and this is not an article about complex crater formation. Sciencebuilder (talk) 17:02, 19 December 2021 (UTC)

Second oldest or third oldes known crater?

In the beginning of the article:

"It is the second-oldest known crater on Earth, after Yarrabubba crater."

In the Section "Formation and structure":

"It is the second-oldest known crater on Earth, a little less than 300 million years younger than the Suavjärvi crater in Russia."

Seems like the age of the Suavjärvi crater isnt that clear (see discussion page of Suavjärvi crater).

Either way, the two sentences are contradicting each other. — Preceding unsigned comment added by 91.217.145.35 (talk) 05:44, 17 January 2022 (UTC)

The contridiction between the Vredfort impact structure being the second oldest or third oldest known impact structure might be because some Earth scientists still dispute whether the putative Suavjarvi impact structure is either a real impact structure or a misinterpretation of ordinary geologic features for which evidence of shock metamorphism is completely lacking. Depending on whether a source regards the Suavjärvi impact structure is a valid extraterrestrial impact or not, will make the Vredfort impact structure either the second oldest or third oldest known impact structure. Regardless of the validity of the Suavjärvi impact structure, there is no crater associated with the Vredefort impact structure as its crater has long since been destroyed by erosion.

For comments on the Suavjärvi impact structure, go see:

Huber, M.S., Plado, J., and Ferrière, L., 2013, Oldest impact structures on Earth—The case study of the Suavjärvi structure (Russia), in Proceedings, Large Meteorite Impacts and Planetary Evolution V: Lunar and Planetary Institute Contribution 1737, abstract 3073.

and Reimold, W.U., 2007. The Impact Crater Bandwagon:(Some problems with the terrestrial impact cratering record). Meteoritics and Planetary Science, 42, pp.1467-1472.

Yes, the sentences contradict each other, which can be fixed after further investigation of the situation. Paul H. (talk) 00:57, 8 July 2022 (UTC)

Article name needs to be corrected to "Vredefort impact structure"

The name of this article needs to be corrected to "Vredefort impact structure". This not an impact crater, which is the topographic expression of an impact. In case of the Vredefort impact structure, the original topographic expression of the impact, its crater, has been long since been destroyed by erosion leaving only the deformed bedrock , which is the impact structure, behind. Paul H. (talk) 20:09, 24 June 2022 (UTC)

I support the proposed renaming or "Vredefort Dome", which is used even more often, but "Vredefort impact structure" is used often enough and both are used far more often than "Vredefort crater". Mikenorton (talk) 19:07, 3 July 2022 (UTC)

After searching through both Google Search, Google Scholar, and GEOREF, I agree completely that this article should be renamed "Vredefort Dome" instead of "Vredefort impact structure". "Vredefort Dome" is most commonly used in the professional and lay publications and has historical precedence over the other names. Also, "Vredefort Dome" is what is used in naming the Vredefort Dome World Heritage Site. Paul H. (talk) 02:29, 4 July 2022 (UTC)

After reading through Kent G. Budge's comments below, I changed my mind, I will go with "Vredefort impact structure". Paul H. (talk) 02:38, 4 July 2022 (UTC)

Requested move 4 July 2022

The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: moved. (closed by non-admin page mover) — Ceso femmuin mbolgaig mbung, mellohi! (投稿) 06:05, 11 July 2022 (UTC)

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Vredefort crater → Vredefort impact structure – Per some preliminary discussion at Wikipedia_talk:WikiProject_Geology#Renaming_"Vredefort_crater"_article, and on this talk page, formally proposing the move. I think either Vredefort Dome or Vredefort impact structure would be better than the present title, and both are used in the literature. I somewhat favor Vredefort impact structure on the basis that the Vredefort dome is apparently but one element (albeit important) of the impact structure. Kent G. Budge (talk) 00:08, 4 July 2022 (UTC)

• Support - Based on what I've been able to find from Google Scholar, both "Vredefort impact structure" and "Vredefort Dome" are much more commonly used than the current title. Accepting the view that "Dome" refers in some cases to only part of the structure, I'm happy to support the proposed renaming. Mikenorton (talk) 12:18, 4 July 2022 (UTC)

• Support per nom. Hemiauchenia (talk) 07:38, 5 July 2022 (UTC)

• Support per nom. Paul H. (talk) 15:12, 5 July 2022 (UTC)
• 'Support No real reason to oppose when the redirect will ensure the article will still be easy to find to laymen. Licks-rocks (talk) 11:47, 10 July 2022 (UTC)

The discussion above 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.