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Tennessee Crater Inches Toward Recognition
tetrahedrassface writes "Slashdot carried the story of an-as-yet unverified impact crater in Tennessee a couple of years ago. After a few weeks of fairly hardcore sample taking, digging, obtaining some good images and manipulating them, I'm proud to report the first batch of evidence in favor of it being an impact site. The primary smoking gun is the presentation of an astrobleme, obtained from High Resolution Ornithographic Images taken in 2008. Also of note are the melted/deformed rocks, magnetic crater dust, and the fitment of the crater rim to a circle. A rented plane and a bunch of photographs today and it's pretty obvious that it's a crater, folks. Cheers!"
ornithographic or orthographic?
"To stop the terrorists."
... High Resolution Ornithographic Images ...
As taken by birds? Perhaps you meant orthographic?
"Tongue tied and twisted, just an Earth bound misfit
He's gotta be around there somewhere...
They fact they found a pair of boots next to a jug by the crater leads me to believe some ones still blow up on them.
Is there something spectacular about this particular dimple in the earth?
Well, yeah! This one hasn't been completely weathered away like most of the others. Sheesh. After all, these things don't tend to stick around all that long, geologically speaking, and it's not like we have an airless moon close by covered with the damned things ... Oh, wait.
"Tongue tied and twisted, just an Earth bound misfit
He's not proud of the crater, he's proud of all the work he's done to verify that it's a crater. Learn to think before writing and the quality of your post will increase dramatically.
It happened a long time ago. No one had anything to do with it.
It's in Tennessee, God put it there.
Do what thou wilt shall be the whole of the Law - Aleister Crowley
Clearly the scientists behind this investigation are a trifle flighty.
Makes more sense than being proud of a sporting team, when it comes right down to it. Using your talents to "discover" such a wonder is a fantastic thing.
Linking to a server via IP address on Slashdot, huh? Yeah, that's going to hold up.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
The primary smoking gun is the presentation of an astrobleme, obtained from High Resolution Ornithographic Images taken in 2008. Also of note are the melted/deformed rocks, magnetic crater dust, and unusual parts from the alien spacecraft that crashed there .
Fixed that for you.
The ironic part of this statement, is that this crater is within just a few miles of the Dayton TN - where the scopes trial took place!
Anyway, it's pretty a pretty cool find, I guess. And considering that the appalachian mountain range is the oldest exposed range on earth, it wouldn't surprise me to find many such ancient events, if we were to look close enough.
This area of the world is actually pretty interesting in regards to human history, fauna, indian history and geologic history. We would be wise not to spoil it too much more. I have a US Dept of Interior Survey from the early 1900's with b/w pictures displaying the complete deforestation of most of it. Much of what we see is replanted from the last 100 years.
I will say, aside from this guys personal relationship to the event, how is this significant? If I remember correctly, someone has postulated that the entire city of Nashville TN is within a large impact crater...
That particular expression makes me think of this http://en.wikipedia.org/wiki/More_Crap. Lots of "proud" people there too.
Considering the relative proximity to this extremely badass crater, I'll consider it.
On a different note; oh how beneath the glorious reign of Reinheitsgebot I'd love to have a corpulent barrel of dunkel in this place.
Forward! -- Emperor Norton, 2012
someone has postulated that the entire city of Nashville TN is within a large impact crater...
I would call that premature cratering.
Looking at the last link - a photo - it's most certainly not "pretty obvious" it's a crater. given the area we're talking about, it could quite easily be the remnants of an old, rather large, sinkhole.
#DeleteChrome
"A rented plane and a bunch of photographs today and it's pretty obvious that it's a crater, folks."
Only if "crater" means "circular depression". Sinkholes make nice circular depressions also, and are far from rare in the South. And the summary misuses the term "astrobleme" which means "cosmic impact crater" and would be the whole circular structure. I gather the poster is referring to an elevated region in the center which may be an impact rebound peak.
Melted rock and magnetic dust makes the case stronger (but ancient volcanism could account for at least the melted rock), but the real smoking gun that would make the case without any doubt would be coesite or stishovite (for example), quartz that has been transformed by megabar (millions of atmospheres) of pressure. These materials (or other evidence of extremely intense shock waves such as characteristic microfractures) are virtual proof of a cosmic impact.
Second class citizen of the New Gilded Age
Yeah, it's not like anybody on Slashdot is interested in science or anything.
Possible. But I'd sure want to exclude karst features (e.g., sinkholes) before accepting an impact origin for a topographic feature in a known karst area. Mapped karst features are awfully close to where the "crater" site is.
Also, your shattercones don't look like real shattercones, which have a nested, cone-shaped geometry. What you illustrate looks more like an ordinary concoidal fracture. Break a rock by any method and you can get those.
If you want to identify impact melt convincingly, then ordinary macroscopic pictures won't do. You need a thin section and some petrographic microscope work. Sometimes even forest fires can melt rocks on the surface, or a camp fire if it is big enough.
Some terrestrial minerals are highly magnetic, but also quite resistant to weathering, and will get left behind (and even concentrated) while other minerals are altered. For example, magnetite. If it were demonstrated to be metal (i.e. unoxidized), especially if a combination of iron and nickel, that would be suggestive, but you'd still have to exclude man-made contamination.
Missing from your sampling is context. Disconnected rocks removed from their geological context are not as useful as understanding how they were arranged in the field. This is especially true for features like shattercones, which should have a clear geometrical relationship to the crater (i.e. basically a radial arrangement). If you are sampling from rubble on the surface, rather than bedrock, you really don't know what you've got. It could be transported by river, gravity (mass wasting), or (not sure if possible at this location) glaciers. It might not even be local. A lot of your samples have lichens and weathering rinds suggesting that these aren't particularly fresh samples (this is why geologists bring geological hammers and suitable eye protection to use them).
In short, you've got an interesting feature, but you are still far from demonstrating it is a crater.
Of course it is inching. It is, after all, riding on a tectonic plate!
Silence is a state of mime.
The crater is in Hamilton County which is along the southern border of the eastern part of the state. Looking at a geologic map of the region, the county is sitting on rocks from somewhere between Cambrian and Ordovician in age (about 540-440Ma). However, the region's geography is dominated by a thrust-and-fold mountain belt that formed during the Alleghenian orogeny about 325-260Ma. The crater is undeformed so it has to post-date the collisional event. Its definitely less than 260Ma. Considering how symmetrical the crater is, its probably a lot younger but I can't find any sedimentary maps for the area.
Or, you could ask a local Tennessee student and s/he will tell you the crater was formed when God smote Satan 10,000 years ago.
The smoking gun will be shocked quartz.
Sorry, I'm not seeing it. Everything I see posted here can be adequately explained without the presence of an impact. Sinkholes are also often round. Magnetic material can accumulate in and weather out of most rock types, and can be introduced through secondary contamination. Vugs are, and other holes/porosity often are, the result of dissolution and weathering (coincidentally, the same processes form sinkholes under the right conditions).
To convince me, do several things:
1. Cut open the weird looking metal pieces and acid-etch them to reveal any Widmanstätten patterns. (Note: the metal in meteors will not react quickly to water or other weak acids, but limestone will. Iron minerals commonly occur in most rock types, not least of all sedimentary rocks, including limestone, that are likely to form sinkholes. Magnetic minerals are actually pretty common. I'd be a little surprised not to find small grains of magnetic material pretty much anywhere on Earth.)
2. Take the rocks to an expert and get an opinion. This often annoys most geologists a little bit since, as one recounted to me, he's had hundreds of people bring him "meteorites" over the years and precisely zero of them were actual meteorites. But if you can get an appropriately trained geologist to glance at them it should be moderately easy to see that they are or are not meteorites, or represent a rock that has melted. If that person can't say definitively, he/she may be sufficiently intrigued to investigate further.
3. If the rocks look interesting to the geologist, running through an electron microprobe and electron microscope will reveal many more interesting things about their precise chemical composition and microscopic structure, as will thin sections under an optical microscope. For the metallic parts reflected light microscopy will tell a great deal. The presence of certain high pressure SiO2 polymorphs is diagnostic in rocks from the impact zone, and iron/nickel composition is a very good indicator in a suspected meteorite.
4. Careful mapping will help, as will a geologic map of the area. Geologic mapping is not difficult, but defensible results require practice and a thorough understanding of geologic principles. Look for the character of the ground, the distribution and size of different material both vertically and laterally, its composition, texture, the nature of contacts between areas with different materials, and the orientation of any different layers, amongst any other notable characteristics. Relate your findings to those on existing geologic maps. Create your map on top of a high resolution topo map.
5. Consider multiple working hypotheses, and keep an open mind. For example, the two obvious hypotheses are that this feature represents a sinkhole or that it instead represents an impact crater. Find as much evidence as you can that contradicts or informs both of those ideas; consider all evidence in light of them. For example, you might observe that the area is characterized by shallow crystalline silicate metamorphic bedrock that is not subject to dissolution, thus pointing away from a sinkhole origin. On the other hand, you might note there are caves in the area, topographic maps show creeks and stream ending abruptly, that there was cement production there in the late 1800s, limestone clasts show traces of pyrite, and there's little evidence of breccia.
It's a logical fallacy to conclude an unusual process must be responsible for an observed feature when your evidence can be adequately explained by more pedestrian processes. Make sure you have solid evidence that can't be explained by more mundane processes before jumping to a novel conclusion -- ad hoc conclusions are inimical to real understanding and the process of science. If an impact is still a reasonable explanation after carefully considering your evidence in light of other hypotheses, systematically write up your findings. Start by giving an overview of the general area, then the feature itself, then the details of specific observations you've made a
Alternatively: It's Tennessee, what else is there to be proud of there?
And exactly what have you done to be proud of, neckbeard?
I'm a professional scientist with a pile of published papers, and I'm here to say that amateur science is a very good thing. Who are we to tell young Calvin to turn off his inquisitive mind when he hits puberty? The guy who wrote TFA is a *far* more interesting person than the people who're mocking him.
Now, do I believe that he's right, and this *is* a crater? Nope. I suspect it's wishful thinking. Does his work meet the standards of peer-reviewed scientific literature? Definitely not. Does his work meet the standards of Slashdot? I dunno, does Slashdot have standards? All I can say is I'd rather read articles like this than the Apple flame wars or hackneyed political debates that fill the rest of the news feed.
So if a meteor took out Nashville and its five major universities, the IQ of the state would double? Yeah, that math works out. Proving your own point?
That's where Uncle Jeb's moonshine still blew up in 1925!
Have gnu, will travel.
Feature is at Lat 3518'53.39"N and Lon 8458'57.22"W
Geology/bedrock info can be found at http://mrdata.usgs.gov/geology/state/state.php?state=TN
The bedrock at that spot is a dolostone, i.e. a carbonate rock that does dissolves and form karst features (like caves, sinkholes, etc.). Description is at http://mrdata.usgs.gov/geology/state/sgmc-unit.php?unit=TNOCAk;10
There are plenty of ponds and closed depressions in the same area if you surf around on Google Earth. My guess is it is not an impact crater.
How to explain the metal, "impacted rock", etc.? People are always burning stuff so it is probably melted metal and slag. Some historical research might be helpful--I can imagine people have been dumping junk and trash there for a long time. What else do you do with a hole in the ground...
Where is the Coesite and what is the condition?
And when found are there neutron damage tracks in the crystals?
!
I expect no replies to this message and the Moderator will delete it, obviously. .|.. (the 'Bird' ... in ascii)/
"The Bible Says..." God punched Satan in the face and that thar impact crater is where he landed, in the time of fire breathing dragon demons n stuff. Must've been one epic battle hallelujah!
35.315003,-84.982424
Can someone please check my impact crater candidates? Maybe they have already been determined.
now we need to go OSS in diesel cars
where is Tennessee, azeroth or tyria?
fucking moron
I live in TN; retard capital of the world.
If a meteor took out Nashville, the IQ of the state would double.
If it took out Memphis, the same thing could happen.
Maybe so, but that would have to be one smart meteor.
All the smart people are in enclaves, close to universities; most are from elsewhere, often overseas.
It's a sad world we live in...
Correction- it's a sad world you live in. Most of us don't live in TN.
I went to middle and high schools in TN, and 2 years of college (on the east side though, in Knoxville). Now I live in Arizona. I think you're mistaken about which state is the retard capital of the USA. Actually, they may be neck-and-neck, having lived in both, it's hard to pick one as a clear winner.
Also, the Creationist Museum is located in Kentucky....
I also spent some time in Mississippi living with a relative over the summer in high school. I think that state may have all the above beat.
No, but most other people on this site are Americans, and it's not much better (and sometimes worse) in most other states in the country.
The Smoky Mountains National Park is actually a very nice place. I also hear Chattanooga is a cool city with good tech (for its size). Memphis has an undeniable musical legacy, though these days it's probably not a great place to be. The weather's pretty decent; doesn't get too cold or too hot. It's not a perfect state, but it has its plusses. And, it's better than Mississippi.
The highest rated comments criticizing the work give tips on how to do the work properly, so that if it IS a crater and not a sinkhole that can be demonstrated, instead of just guessed at.
Not a sentence!
Number 1 is Hicks Dome, a structural dome related to igneous processes.
Number 2 looks like erosion at the interface between different geologic layers, probable a ridge of Monongahela Group sandstone and softer Conemaugh Group shale and siltstone. There's nothing about it besides a little bit of roundness that's very crater-like. If this structure has a name I don't know what it is. The fact that it appears to be at the intersection of topography that's very steeply eroded to the west and more subtly incised to the east suggests it's a chance erosion feature between two different rock types of different toughness. If you look around that area you'll see there are lots of other eroded bowls. These are common shapes that peaks and ridges take as they erode.
Number 3 is I think called Burke's Garden, representing an eroded structural dome in an area of complex folding and thrust faulting in the ancient roots of the Appalachian Mountains. The outer, younger, sandstone layer was eroded way providing access for the elements to go to work on the less resistant shale and Knox Group limestone and interior. If you scroll around a bit you can see many ridges running running along the mountains, some of which are folded, faulted, and eroded in to similar structures -- just generally with a finer aspect ratio. This section of strata just happened to get abused by the just right combination of folding and thrust faulting in the right places to make the structure look a little rounder than most. Simple geologic mapping (which has already been done -- you just need to find a copy of the maps) should very conclusively demonstrate the structural features you see here are exclusively accounted for by the conventional compressive orogenic processes that formed the core of the ancient Appalachian Mountains.
'Tis a shame you're an AC for then I could mod you up.
..it's at this link http://goo.gl/maps/Oe78J
I'd have to say that it looks nothing like a meteor crater and a lot like a sinkhole caused by an underground collapse. Meteor craters that size would be very round and would cause circular deformation of the surrounding area.
Siderite found in the depression would exactly match what was shown on the website.
You're welcome.
Tubby or not tubby. Fat is the question
As a scientist I will *NOT* fault enthusiasm and simply trying to figure something out. Does he have a convincing scientific case? No. But I have no problem with people trying to learn. Geology can be a difficult subject to get into because there is so much background information to learn. However, it's one of the sciences where you don't necessarily need plenty of expensive lab equipment to figure something out. A lot of geology you can do just by being observant in the field and taking good notes and photographs as you map structures across an area. For an impact crater, well, unfortunately the best techniques still need a thin section, a petrographic microscope, and a whole lot of training to interpret thin sections, but even so this is well within the range that a non-expert can achieve if they put the effort into it. And who knows? Maybe he will discover something interesting.
But faulting someone for trying? That's just mean. Next I suppose you'll ridicule someone who knows little about computers for trying to install a Linux distribution on their PC. They have to start somewhere.
Think of this as geological "hacking". It's still at a pretty simple stage, but Slashdot is as good a place as any to talk about it.
For every stupid racist redneck in this state there is an equally amazing natural beauty. There's the Smoky Mountains, there's the parks, there's Nashville, a music capital from back when music sucked just a little less (regardless of your opinion on Country music, and personally I don't really like it, but I know what's what). There are forests, mountains, lakes, Native American culture, family histories from the early days of this country. Tennessee isn't the problem with Tennessee, there's much to be proud of here. The problem with Tennessee is the aforementioned bigoted, racist, fundie wingnut rendecks.
I don't think that it is "pretty obvious it is a crater". Prime evidence is missing or not well enough illustrated.
First:
1) as others here remark too, a circular feature does not equal an impact crater. Karst depressions are circular too and a strong candidate in this area;
2) magnetic particles can be found in any soil. They do not point to impact as such. Show us geochemical tests that show they are of meteoritic composition, and show us that they have an abundance well over the natural accretion rate of cosmic dust for this sedimentary regime
What is needed is:
a) a clear record of a breccia fill;
b) a clear record of overturned rim strata;
c) a clear record of shock-deformed quartz;
d) more convincing examples of shatter cones;
e) more convincing examples of impact melt breccia, including identification of the mineral phases that associate with such rock.
The presence of clear meteoritic components (geochemically shown to be extraterrestrial in composition) in the crater sediments would be a good argument as well, but they are not always preserved in genuine meteor craters. The magnetic particles you present do not count as such, as I already pointed out.
Regarding (d) and (e): the photographs of purported specimens provided are far from convincing. The "shatter cone" actually looks like a shard of rock with a conchoidal fracture on the ventral face, not a 3D shatter cone. And the "melt glass"? Not clear enough from the pictures: it could be anything. The "tortured rock" (purported impact melt) actually looks like a porous carbonate such as you can find in karst features, not like a vesiculated impact melt.
Ceterum censeo Carthaginem delendam esse
Cool sig bro, maybe there's a corollary?
All that's needed for Ignorance to succeed is for intelligent men to do nothing (or whine about it while doing nothing)
I've tested these with acid. If the sample won't react with boiling acid (nitric or sulfuric) why would it stand to reason they are carbonates reacting to rainwater?
They don't react with boiling hydrochloric either..
Yeah, and if it wasn't just a big sinkhole, I'm sure his pride would be well placed. As it stands however... Well, he should be proud of all the work he did, but he should be less proud that he from evidence that clearly points to "no" still drew whatever conclusion he wanted rather than what the evidence pointed to.
Picture of sample here: here.
No rxn. That rock looks normal too.... shure... anything but heated and pressed.. amirite?
Maybe I'm blind, but I couldn't find this thing's latitude/longitude location, anywhere. I tracked it down using some of the pictures on the guy's website.
I found that it is located at: 35.313724 N and 84.977574 W
http://goo.gl/maps/jgJyJ
Note that the photo with the houses at the very top would be taken from the eastern edge of the map with those houses being along Pierce Road pretty much straight over from the bottom "-" of Google Maps' magnifier tool. From the ariel view it could be a sinkhole or a crater, with sinkhole being more common in the area. Someone mentioned below that there is a disappearing stream just a mile from there. That part of Tennessee has some magnificent caves.
Anyway, I hope the poster will ignore the haters and keep on it. I remembered this post from a couple of years ago and the vitriol then. Keep on it. Worst case is you prove it's a sinkhole. But at least you've done something, learned a lot, educated others, etc. It's interesting work, and even if it is a sinkhole it's a freaking monster of a sinkhole - still interesting in its own right. And a sinkhole that big is draining into a sizable cave.
Do you have ESP?
Alternatively: It's Tennessee, what else is there to be proud of there?
The plutonium reactor powering the Mars rover Curiosity is one that comes to mind. I know one of the guys that produced the fuel in the High-Flux Isotope Reactor at the Oak Ridge National Laboratory.
We're trying to clean it up.
In the mean time, go to www.redstateupdate.com