Daniel Frew Posted September 22, 2016 Share Posted September 22, 2016 Came across this one along Hurricane Creek in Pope County Arkansas. At first thought it was a crinoid imprint but now wonder if maybe its just a trace fossil. Link to comment Share on other sites More sharing options...
DPS Ammonite Posted September 22, 2016 Share Posted September 22, 2016 What formation are they from? Take some photos of the ends of the tubular structures please. Are the tubes depressions or convex and stick out? EDIT: They now appear to be impressions (exterior molds) of a fossil, possible crinoid stems. They don't appear to be trace fossils such as burrows, because most burrows have infilling preserved and don't have such sharply defined curved lines in them. My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
njfossilhunter Posted September 22, 2016 Share Posted September 22, 2016 Also try this link...... http://paleoaerie.org/arkansas-fossil/ TonyThe Brooks Are Like A Box Of Chocolates,,,, You Never Know What You'll Find. I Told You I Don't Have Alzheimer's.....I Have Sometimers. Some Times I Remember And Some Times I Forget.... I Mostly Forget. Link to comment Share on other sites More sharing options...
Raggedy Man Posted September 22, 2016 Share Posted September 22, 2016 They kinda look like Paleophycus sp. a trace fossil made by worms. Maybe this will help, maybe not. Best regards, Paul ...I'm back. Link to comment Share on other sites More sharing options...
Rockwood Posted September 22, 2016 Share Posted September 22, 2016 I'd stay with crinoid molds. They are just weathered a bit past their prime. Link to comment Share on other sites More sharing options...
TqB Posted September 22, 2016 Share Posted September 22, 2016 It looks like a good example of the ichnogenus Arthrophycus. See this thread: http://www.thefossilforum.com/index.php?/topic/44552-id-help-please/ Tarquin Link to comment Share on other sites More sharing options...
Rockwood Posted September 22, 2016 Share Posted September 22, 2016 36 minutes ago, TqB said: It looks like a good example of the ichnogenus Arthrophycus. See this thread: http://www.thefossilforum.com/index.php?/topic/44552-id-help-please/ A "good" example ? Link to comment Share on other sites More sharing options...
TqB Posted September 22, 2016 Share Posted September 22, 2016 7 minutes ago, Rockwood said: A "good" example ? I would say so, given the plate from Seilacher, Trace Fossil Analysis. May be wrong though... Tarquin Link to comment Share on other sites More sharing options...
Rockwood Posted September 22, 2016 Share Posted September 22, 2016 32 minutes ago, TqB said: I would say so, given the plate from Seilacher, Trace Fossil Analysis. May be wrong though... I'll give you possible example, but I don't think either of us had been born when this was a good example. What do you think precludes the crinoid mold alternative ? Link to comment Share on other sites More sharing options...
fossiling Posted September 22, 2016 Share Posted September 22, 2016 I'm a newbie at this, but i think it's cruziana sp.? Keep looking! They're everywhere! Link to comment Share on other sites More sharing options...
TqB Posted September 22, 2016 Share Posted September 22, 2016 48 minutes ago, Rockwood said: I'll give you possible example, but I don't think either of us had been born when this was a good example. What do you think precludes the crinoid mold alternative ? Mainly because I saw at least some of it a as a positive relief, made of sandstone - which my brain still wants to do... (in which case some of the tubes are still buried and it is a good example). If all the pieces are negative relief, I grant it looks more crinoid like. The apparent columnal spacings are maybe rather irregular. Tarquin Link to comment Share on other sites More sharing options...
DPS Ammonite Posted September 22, 2016 Share Posted September 22, 2016 @Daniel Frew We need a photo taken of the top edge of the fossil, and a comment from Daniel (which would help us to ID the fossil) regarding whether the fossils are imprints or are of positive relief. My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
abyssunder Posted September 22, 2016 Share Posted September 22, 2016 That is the question, I agree. Every time I take a look at the specimen I see it different. I had once the same dilemma, with the positive or negative in 3D. It's a trick of light. I consider that the source of the light in the photo is somewhere in the upper-right corner to make possible all the shadows to be in the right place, including that one marked with green arrow in my picture. In this condition the specimen reveals imprints in the matrix. If the light source is in the upper-left corner, making possible to believe that the "traces" are out of the matrix, all the shadows could be in the right position except one : that with the green arrow marking. That's how I see the whole ensemble, so, I conclude, that there are imprints of something in the matrix. " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
Rockwood Posted September 22, 2016 Share Posted September 22, 2016 I'm red green color blind. Is there really an arrow here ? Link to comment Share on other sites More sharing options...
abyssunder Posted September 22, 2016 Share Posted September 22, 2016 If the image is converted to grayscale, I have to agree with you, the arrow is almost invisible, but the shadow is right there. " We are not separate and independent entities, but like links in a chain, and we could not by any means be what we are without those who went before us and showed us the way. " Thomas Mann My Library Link to comment Share on other sites More sharing options...
Fossildude19 Posted September 22, 2016 Share Posted September 22, 2016 1 hour ago, Rockwood said: I'm red green color blind. Is there really an arrow here ? There you go. Fixed it for you. Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Rockwood Posted September 22, 2016 Share Posted September 22, 2016 Got it, thanks. It was an effort for me to see it the other way. The lighting that is. Link to comment Share on other sites More sharing options...
Daniel Frew Posted September 26, 2016 Author Share Posted September 26, 2016 Sorry but I've been working a bunch of hours and forgot to check on these. It is impression into the rock. Dan Link to comment Share on other sites More sharing options...
DPS Ammonite Posted September 26, 2016 Share Posted September 26, 2016 Impressions indicate that it is a body fossil and not a trace fossil. Crinoid stems are most likely. It always amazes my how the brain can look at a fossil photo and think that it is concave one time and convex another. Written descriptions of posted fossils using terms such as "concave", "convex" or "impressions" are helpful. My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
tmaier Posted September 26, 2016 Share Posted September 26, 2016 Because of the way that these overlay eachother, I have to go with tyrace fossil. If they were solid columal objects, they couldn't do that, they would be passing through each other. This was formed by the overlay of a trace, then the superposition of another trace over that, etc. Not by a pile of solid objects. Link to comment Share on other sites More sharing options...
TqB Posted September 26, 2016 Share Posted September 26, 2016 Just to throw in another possibility, it could be an impression of a bed of rugose corals like this: http://www.habitas.org.uk/fossils/siphonophyllia.html What size are they? - it might help. Tarquin Link to comment Share on other sites More sharing options...
Raggedy Man Posted September 26, 2016 Share Posted September 26, 2016 11 minutes ago, TqB said: Just to throw in another possibility, it could be an impressions of a bed of rugose corals like this: http://www.habitas.org.uk/fossils/siphonophyllia.html What size are they? - it might help. Nice TqB. That is definitely a high possibility and close match. ...I'm back. Link to comment Share on other sites More sharing options...
tmaier Posted September 26, 2016 Share Posted September 26, 2016 But then the corals would have to be passing through each other... an unlikely possibility. Link to comment Share on other sites More sharing options...
TqB Posted September 26, 2016 Share Posted September 26, 2016 1 hour ago, tmaier said: But then the corals would have to be passing through each other... an unlikely possibility. I'm just seeing whatever they are as twisting together a bit - as all the tubes are impressions, I think that works... An Arthrophycus-type trace fossil still looks a possibility though. Tarquin Link to comment Share on other sites More sharing options...
Raggedy Man Posted September 26, 2016 Share Posted September 26, 2016 2 hours ago, tmaier said: But then the corals would have to be passing through each other... an unlikely possibility. I agree with the premise, but I think compression of the specimens and the 2 dimensional image create an optical illusion. The specimen on the top,(provided by TqB) is in a limestone matrix. The specimen in the middle(the one in question) is in a sandstone matrix. Both matrices offer different types of preservation(casts,molds/organic replacement). Crinoid stems, corals, ichnofossil all seem to be valid observations. I used to study thermophiles and one could say that this specimen also resembles tube worm communities(bottom image) that colonize the ocean floor around volcanic ducts. The measurements of the specimen in question would help immensely. Do you know if this piece is native to the area found? It could of been trucked in and dumped as rifraf. Best regards, Paul ...I'm back. Link to comment Share on other sites More sharing options...
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