Posted on 03/01/2022 8:06:31 AM PST by Red Badger
The Yilan crater. (NASA Earth Observatory/Lauren Dauphin/Landsat data/USGS)
A crescent-shaped crater in Northeast China holds the record as the largest impact crater on Earth that formed in the last 100,000 years.
Prior to 2020, the only other impact crater ever discovered in China was found in Xiuyan county of the coastal province of Liaoning, according to a statement from the NASA Earth Observatory.
Then, in July 2021, scientists confirmed that a geological structure in the Lesser Xing'an mountain range had formed as a result of a space rock striking Earth. The team published a description of the newfound impact crater that month in the journal Meteoritics and Planetary Science.
The Yilan crater measures about 1.15 miles (1.85 kilometers) across and likely formed about 46,000 to 53,000 years ago, based on radiocarbon dating of charcoal and organic lake sediments from the site, the NASA statement says.
Researchers collected these sediment samples by extracting a drill core from the center of the crater, Forbes reported.
Beneath more than 328 feet (100 meters) of layered lake and swamp sediments lay a nearly 1,000-foot-thick (320 m) slab of brecciated granite, which is granite made up of many rocky fragments cemented together in a matrix, the team found. This rock bears telltale scars of having been struck by a meteorite.
For example, fragments of the rock show signs of having melted and recrystallized during the impact, as the granite rapidly heated and then cooled off. Other fragments of the rock escaped this melting process, and instead contain "shocked" quartz that shattered in a distinct pattern when the space rock crashed down, according to Forbes.
The team also uncovered teardrop-shaped glass fragments and pieces of glass pierced with tiny holes made by gas bubbles; both of these features also indicate that a high-intensity impact took place there, according to the NASA statement.
A portion of the Yilan crater's southern rim is missing, so the geological structure looks crescent-shaped from above, the Global Times reported. Such crescent-shaped impact craters are relatively rare on Earth, Chen Ming, one of the authors of the article and a research fellow from the Guangzhou Institute of Geochemistry, told the Global Times.
In October 2021, the Landsat-8 satellite captured a striking snapshot of the crater's northern rim, and scientists are now investigating how and when the southern rim disappeared, according to the NASA statement.
The so-called Meteor Crater in Arizona previously held the record for largest impact crater less than 100,000 years old; it's about 49,000 to 50,000 years old and measures 0.75 miles (1.2 km) in diameter. The Xiuyan crater, by comparison, measures 1.1 miles (1.8 km) across, but its age is unknown, Forbes reported.
I heard that they think the lake in the middle of all that is a crater.🤔
That could very well be, but the last documentary I saw on it, it was a shallow radioactive bog. That’s been several years ago, and I believe it was a Russian production, so they could have changed the narrative.
Who knows what is really there or why, and why is it so important to circulate different stories? Just rhetorical, but you know: inquiring minds and all that! ;o]
Shouldn’t that read ‘’was formed’’?
A crescent-shaped crater in Northeast China holds the record as the largest impact crater on Earth that formed in the last 100,000 years....
That's BAIT AND SWITCH. The headline states "Largest Known Crater on Earth," without further qualification. Then the body of the story moves the goalposts and makes it about "impact crater[s]."
The explosion of the Toba volcano ca. 75,000 YA left a crater about 497 miles long and 22 miles wide, which fits in their 100,000 year historical window and is more than 3000 times the size of this pipsqueak.
And unless I'm very much mistaken, the Vredefort impact crater in South Africa is the largest known at a roughly circular 190 miles diameter, much YUGER than Meteor Crater in Ariz.
I grew up in a city built in a meteor crater and still work there near ground zero.
https://www.appalachianhistory.net/2016/11/town-built-inside-crater.html
yeah the pictures didn’t look like any indent- or crater- more just flattened area- musta been a whopper of an explosion-
Exactly.
I don’t recall the altitude but it seems it was at least a mile. Even at that high, it must have been HUGH!
Well, we puny humans are calling it the Meteor Crater, but we don’t know how it self-identifies. Maybe it thinks of itself as the Tiny Asteroid Crater.
Seriesly Hugh! lol
Vreedervoort?
The impact crater that was formed in China is 1.1 to 1.15 miles in diameter. Our Sunken Civ reported a few years ago on one that may have destroyed middle east civilizations a little more than 4,000 years ago. It appears to be about 2 miles wide and is in the Iraq marshes that Saddam tried to destroy. SC, time for the BOOK, and any good links to the Iraq find.
https://www.downtoearth.org.in/news/cosmic-collision-17290 [the Iraq marsh find]
Someone mentioned causes of the Younger Dryas cooling. Actually there is a whole book which discusses meteor events which may have triggered the YD around 13,000 years ago. It shows a bottom profile of Lake Michigan and proposes two meteor strikes. I think I see a third smaller one between the 2 larger ones which make it look like a giant ant. I also discovered another sign of meteors when I was reading about the First Intermediate period (of disaster) in Egypt around 4,000 years ago which was described vividly in the Ipuwer papyrus which is in Leyden. Apparently Argentina also experienced meteors (Campos del Cielo) a little more than 4,000 ya. Perhaps both the Iraq and the Argentine events were part of a group of meteors, as it appeared the North American events 13,000 ya had been.
A correction on Toba, possible typo, the crater is about 60 miles by 16 miles, but it is volcanic, not extra-terrestrial. The Tungusku explosion was apparently in the air, although a small crater is also possible. It was huge, red skys were seen in England. You may remember the recent Cheliabinsk (sp?) air explosion. Poor Russia. Actually when large Russian meteor was mentioned I first thought this was in reference to a huge crater (multi tens of miles) formed around the same time as the Chesapeake meteor which dug a 65 mile long crater running from Norfolk to Exmore on the Delmarva Peninsula. The funny little bends in some of the coastal rivers like the James were caused by that 34 million ya event. I think the Russian meteor is named something like Popigai which may have been formed as part of a multi blow event. There is also a 10 mile wide crater off the NJ coast.
The only major meteor result I have seen in person is one in Ontario, Canada, called the Sudbury. About 55 years ago we were driving through this area and I was horrified by the damage to the land that had been caused by mining and smelting and toxic deposits. Mile after mile of desolation. The link below has explanations and good maps of the area regarding the nickel and copper mining created by the impact. Second largest crater ever, mostly obliterated, after the Vredifort (sp?).
https://earthobservatory.nasa.gov/images/148844/sudbury-impact-structure
Iraq's "Curse of Agade" crater, probably mentioned in one or all of these:
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