Posted on 08/06/2022 10:50:02 AM PDT by SunkenCiv
An impact origin for the Des Plaines structure was first proposed in Emrich and Bergstrom (1962). The publication contains a general map of the structure, contextual maps of the region, a cross section, rough boughuer gravity map, and discussion of the available observations in terms of the emergent science of impact craters. It renames the structure as a cryptoexplosion rather than cryptovolcanic structure. The paper also records a central uplift displacement of about 600 to 900 vertical feet, a diameter of about 5 1/2 miles, and other general morphometrics. An additional brief description of the structure and a more detailed description of its regional context can be found in Willman, 1971.
An impact origin was confirmed with the discovery of shatter cones and report of shock metamorphic features in quartz grains, reported by McHone et al., in abstracts from 1986 and 1987. More details may be present in Peterson, 1989, and better maps may exist in a Master's Thesis published in 1974 by Langan.
(Excerpt) Read more at impactcraters.us ...
LOL! Yes, Park Ridge is in the impact zone.
Finally....we have gone full Hervy
There is the Sierra Madera astrobleme near Ft. Stockton, TX. You can stop at the crater rim on the highway (US 385) and see the rebound peak in the distance. Most of the crater has filled in and the rim is only a few feet higher than the fill.
Unfortunately, it’s pronounced just like it’s spelled.
Thanks. Also, there was an impact crater in Texas that for some period of time was used as an outdoor concert venue.
Barringer (Meteor Crater is sometimes called Barringer Crater) was the geologist who tried to recover the suspected nickel-iron mass of the meteorite. Found bupkis.
As marktwain pointed out, the impact energy shatters and melts the the impactor along with the ejecta from the crater. This makes for tiny remnant grains flying off in all directions, along with the shocked quartz and other minerals formed or transformed by the heat.
The geologist Eugene Shoemaker was an official witness to one of the a-bomb tests and examined the area around the blast site, discovering these types of materials which had been formed by the blast. That got him thinking about Meteor Crater (which was still not considered an impact crater by most geologists and probably zero volcanologists), so he returned to it and found those very same types of materials.
His paper on the impact origin of Meteor Crater arrived with a resounding thud.
He and Carolyn took a vacay or maybe their honeymoon in the Ries Basin in Germany, with him in search of impact evidence. The local cathedral turned out to be made of locally quarried stone that was absolutely lousy with coesite. That paper generated some curiousity, perhaps because the impact was circa 15 million years ago.
It's okay, y'see, to have the occasional catastrophe, provided it doesn't make the hospital-corners set uncomfortable. Most scientists and their precursors (along with all the flat-earth nimrods) have rejected impacts from space since Aristotle, who stated flatly that stones don't fall from the sky.
Shoemaker's first big success was vicariously, when one of his old students went on Apollo 17 and examined the surface, finding that impact (including continuous micrometeorites for billions of years) is far and away the dominant force at work forming the lunar surface. He'd have been the one doing that, but his adrenal cortex went haywire and knocked him out of the running for Apollo.
However, it wasn't until the fragments of comet SL-9 started pullin' train on planet Jupiter that impact geology, his own creation, became the dominant paradigm.
Thanks, I plan to start posting a topic a week on the various craters to this ping list.
My pleasure.
Cool.
As coroner, he's thoroughly examined Herv, the midget isn't merely dead, he's really most sincerely dead.
Florida has a big one too...
Was the Gulf of Mexico formed by a meteor?
The Gulf of Mexico is too large to have been formed by a meteor impact. However, the Chicxulub crater, which is believed to be the largest meteorcrater on the earth, is found off the Yucatan Peninsula in the Gulf of Mexico.
Thanks!
The Gulf of Mexico could very easily be the remnants of an impact crater. Ironically, its very scale would make it difficult to prove, and its likely age would figure into that difficulty as well.
The Great Lakes appear (just to me) to have been formed by a doublet impact, with the smaller one forming what is now Lake Superior, and the larger forming Lakes Michigan and Huron. Again, very long time ago. We’ve got three common kinds of soil — clay, sand, and muck, with the last one having formed on the bottoms of glacial lakes.
I agree with you on the crater link to the whole system. The edges, the central rise where the earth rebounded, etc. Geologists disagree with you and I, but that is their right to be wrong.
That makes sense to me - and what a wonderful reservoir of fresh water too...
Geologists by and large have come around to impact, but there’s more money in geology to locate economic stuff, oil, precious metals, rare earth, etc.
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